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Utilities Policy,
volume 58,
pages 63-88,

Abstract

Long-term forecasts of the aggregate electric load profile are crucial for grid investment decisions and energy system planning. With current developments in energy efficiency of new and renovated buildings, and the coupling of heating and electricity demand through heat pumps, the long-term load forecast cannot be based on its historic pattern anymore.

This paper presents part of an on-going work aimed at improving forecasts of the electric load profile on a national level, based on a bottom-up approach. The proposed methodology allows to account for energy efficiency measures of buildings and introduction of heat pumps on the aggregated electric load profile. Based on monitored data from over 100 non-residential buildings from all over Norway, with hourly resolution, this paper presents panel data regression models for heat load and electric specific load separately. This distinction is crucial since it allows to consider future energy efficiency measures and substitution of heating technologies.

The data set is divided into 7 building types, with two variants: regular and energy efficient. The load is dependent on hour of the day, outer temperature and type of day, such as weekday and weekend. The resulting parameter estimates characterize the energy signature for each building type and variant, normalized per floor area unit (m2). Hence, it is possible to generate load profiles for typical days, weeks and years, and make aggregated load forecasts for a given area, needing only outdoor temperature and floor areas as additional data inputs.


Lindberg, K.B., Seljom, P., Madsen, H., Fischer., D. & Korpås, M. (2019) Long-term electricity load forecasting: Current and future trends
Utilities Policy,
volume 58,
pages 102-119,

Abstract

Long-term power-system planning and operation, build on expectations concerning future electricity demand and future transmission/generation capacities. This paper reviews current methodologies for forecasting long-term hourly electricity demand on an aggregate scale (regional or nationally), for 10–50 years ahead. We discuss the challenges of these methodologies in a future energy system featuring more renewable energy sources and tighter coupling between the power sector and the building and transport sectors. Finally, we conclude with some recommendations on aspects to be taken into account regarding long-term load forecasts in a changing power system.


ZEN Report 16,
NTNU/SINTEF,

Popular summary in English:

(Scroll nedover for norsk sammendrag)

This report presents results from an ethnographic process carried out by the Research Centre for Zero Emission Neighbourhoods in Smart Cities (ZEN Centre) in collaboration with Steinkjer Municipality in 2017 and 2018. It follows the process of developing a pilot project at Lø in Steinkjer, where a zero emission neighbourhood was planned and which included the upgrading of the old offices of the Norwegian Broadcasting Company in Steinkjer to a zero emission kindergarten. The report describes and analyses the decision-making process and events that took place before March 2018, when the chairmanship of Steinkjer municipality took the decision to demolish the NRK building and build a new kindergarten at Lø. The decision which stopped plans to develop a ZEN pilot project at Lø was based on the wishes of representatives from two kindergartens from Lø, who were to be co-located in the planned zero emission kindergarten.

The process is presented in the form of two main stories. (1) The story about the kindergarten at Lø, where the kindergarten representatives’ reasons for their request for a new, rather than upgraded kindergarten building, are told. (2) The story about the ZEN pilot project in Steinkjer. In this story, the reasons for the enthusiasm for the pilot project by Steinkjer municipality and ZEN researchers are explained. The report asks why two different understandings of the needs of the project were established, and proposes solutions for avoiding disaffection with projects with high energy and environmental ambitions during the early stages of the development process.

In the history of the kindergarten at Lø, there are two main reasons why the kindergarten representatives decided to stop the process of upgrading the NRK building for kindergarten purposes:

1. Prehistory: a lot happened in Lø, around the plans for co-locating the two kindergartens before ZEN became involved.

2. ZEN’s anchoring in Steinkjer municipality: The research centre was known in the Planning and Development Departments, but not beyond that. The representatives from the kindergartens believed that they received too little information about ZEN and about the pilot project development process in general.

During the planning process at Lø, the representatives from the kindergartens experienced that they were not heard, and that the needs of the building users were peripheral to the discussions taking place. When the chairmanship of Steinkjer Municipality took the decision to demolish the old NRK building and build a new kindergarten at Lø, the kindergarten representatives finally felt that user needs were in focus. The kindergarten representatives therefore regarded the story about the process at Lø to be a success story, where user needs were given priority over the needs of the building and pilot project.

For the representatives from the Planning and Development Departments and ZEN researchers the decision to demolish the NRK building was a defeat. They saw no contradiction between the ZEN concept and the kindergarten’s needs and believed that the pilot project at Lø as a fantastic opportunity. However, the municipality and ZEN did not succeed in establishing a common under-standing about what a zero emission kindergarten at Lø would mean in practice that the representatives of the kindergarten were comfortable with. A common understanding about why upgrading of the NRK building was a fantastic opportunity, was never established.

How can we avoid disaffection with ambitious energy and environmental projects?

The user’s needs should be visible from the outset, supported by a thorough and inclusive mapping process that takes place at the start of pilot project development. This will help to avoid, at an early stage, the anchoring of contradictions between everyday needs and ZEN ambitions.

Information about ZEN aims, and ambitions should be available throughout all stages of pilot development, particularly the early phase. Information about ZEN should be easy to understand for wide range of user groups and should clarify why ZEN is a «fantastic opportunity». A forum where all involved parties can listen, and exchange views should be established.

The challenges faced in Steinkjer are unique. Not all pilot projects in ZEN will require the same measures. However, the mapping of user needs and measures to ensure user involvement will always be good investments, with social value in ZEN neighbourhoods and the municipalities where the neighbourhoods are located. The ZEN Centre and its municipal stakeholders are continuously working on information production and exchange. What is lacking is greater focus on who the target groups are and information that is tailored to different user needs.

Norsk sammendrag:

Denne rapporten presenterer resultater fra en etnografisk prosess utført av Forskningssenteret for nullutslippsområder i smarte byer (FME ZEN) i samarbeid med Steinkjer kommune i 2017 og 2018. Den følger prosessen med å utvikle et pilotprosjekt for nullutslippsområder på Lø i Steinkjer, noe som blant annet innebar å gjøre om NRKs gamle kontorer i Steinkjer til en nullutslippsbarnehage.

Rapporten beskriver og analyserer beslutningsprosessen og hendelsene som skjedde før mars 2018. Da bestemte formannskapet i Steinkjer kommune å rive NRK-bygget og heller bygge en ny barnehage på Lø. Avgjørelsen som stoppet planene om å utvikle et ZEN-pilotprosjekt på Lø var basert på ønskene fra representanter fra de to barnehagene som skulle slås sammen i den planlagte nullutslippsbarne­hagen.

Prosessen presenteres i form av to hovedhistorier. (1) Historien om barnehagen på Lø, hvor begrunnelsene for hvorfor barnehagerepresentantene ønsket en ny snarere enn en oppgradert barnehage blir fortalt. (2) Historien om ZENs pilotprosjekt i Steinkjer. I denne historien forklares årsakene bak kommunens og ZEN-forskernes entusiasme for pilot­prosjektet. Rapporten reiser spørsmålet om hvorfor det oppstod to ulike forståelser av behov i prosjektet, og foreslår løsninger for å unngå misnøye i prosjekter med høye energi- og miljøambisjon­er tidlig i utviklingsprosessen.

I historien om barnehagen på Lø kommer det frem to hovedgrunner til at barnehagerepresentantene bestemte seg for å stoppe prosessen med å oppgradere NRK-bygget til en barnehage:

1. Forhistorie: Det skjedde mye i Lø rundt planene for samlokalisering av de to barnehagene før ZEN ble involvert.

2. ZENs forankring i Steinkjer kommune: Forskningssenteret var kjent i planleggings- og utviklings­avdelingene, men ikke utover det. Representantene fra barnehagene mente de fikk for lite informasjon om ZEN og om utviklingsprosessen av pilotprosjektet generelt.

Under planleggingsprosessen av pilotprosjektet opplevde representantene fra barnehagene at de ikke ble hørt og at brukernes behov var perifere for diskusjonene som fant sted. Da formannskapet i Steinkjer kommune tok avgjørelsen om å rive NRK-bygningen og heller bygge en ny barnehage på Lø, følte barnehagerepresentantene endelig at brukerne var i fokus. Representantene betraktet derfor historien om prosessen ved Lø som en suksesshistorie, der brukernes behov ble prioritert over bygg- og pilotprosjektets behov. For representantene fra plan- og utviklingsavdelingene og ZEN-forskerne var beslutningen om å rive NRK-bygget et nederlag. De så ingen motsetning mellom ZEN-konseptet og barnehagens behov. De så pilotprosjektet på Lø som en fantastisk mulighet. Kommunen og ZEN klarte imidlertid ikke å etablere en felles forståelse for hva en nullutslippsbarnehage på Lø ville bety i praksis som barne­hagenes representanter var komfortable med. De ble altså aldri etablert en felles forståelse for hvorfor oppgradering av NRK-bygget var en fantastisk mulighet.

Hvordan kan vi unngå misnøye med ambisiøse energi- og miljøprosjekter?

Brukernes behov bør synliggjøres fra starten av, støttet opp av en grundig og inkluderende kart­leggingsprosess som gjøres i startsfasen av et pilotprosjekts utvikling. Dette vil bidra til å unngå tidlig forankring av motsetninger mellom hverdagsbehov og ZEN-ambisjoner.Informasjon om ZENs mål og ambisjoner bør være tilgjengelig gjennom alle stadier av prosjektets utvikling, særlig i den tidlige fasen. Informasjon om ZEN skal være lett å forstå for et bredt spekter av brukergrupper og bør avklare hvorfor ZEN er en «fantastisk mulighet». Et forum hvor alle involverte parter kan lytte og utveksle synspunkter bør etableres.

Utfordringene i Steinkjer er unike. Ikke alle pilotprosjekter i ZEN vil kreve de samme tiltakene. Kartlegging av brukerbehov og tiltak for å sikre brukerengasjement vil imidlertid alltid være gode investeringer, med sosial verdi i ZEN-nabolagene og kommunene hvor disse ligger. ZEN-senteret og dets kommunale interessenter arbeider kontinuerlig med informasjonsproduksjon og -utveksling. Det mangler imidlertid et større fokus på hvem målgruppene er og informasjon som er skreddersydd for ulike brukerbehov.


Technological Forecasting & Social Change,
volume 142,
pages 142-153,

Abstract

The planning of energy ambitious neighborhood pilots in Norway typically begin with the creation of holistic and socially ambitious visions based on extensive stakeholder collaboration, citizen insight generation and vision setting. However, as projects move from planning to implementation, the exploratory innovation methods are replaced by exploitative approaches. ‘The holistic vision and in particular, citizens’ described needs, fail to transfer into the implementation phase.

This paper identifies four main challenges as to why this happens and link these to theory on ambidextrous organizations that need to exploit existing knowledge while reaching into the future with its rapidly changing goals and technological opportunities. Implementing stakeholders are familiar with exploitative tools, which build on earlier experience and capabilities of the selected implementing stakeholders, and the implementation stage leaves little time and resources for innovation on a lower hierarchical level.

While extensive research on smart and integrated planning focus on ‘breaking down the silos’ meaning sectors and disciplines, our findings argue that the need to manage ambidextrous organizations and support both exploratory and exploitative innovation is equally important. An ambidextrous organization is one that has the ability to be efficient in its management of today’s business while being adaptable for coping with the changing demand of tomorrow. We propose a model in which the organizational style and management style of innovative neighborhood pilots focus more on how to transfer knowledge and learn from the bottom-up and horizontally through management that foster both innovation models.


Sandberg, N. H., Næss, J. S., Gustavsen, A., Andresen, I. & Brattebø, H. (2019) Energianalyse for bygningsmassen i Oslo – Scenarioanalyse av energibruk og klimagassutslipp 2009-2040
ZEN Report 14,
NTNU/SINTEF,

Sammendrag

Det sies ofte at det er et stort potensial for energisparing og reduksjon i klimagassutslipp fra energibruk i bygningsmassen. Som innspill til sin oppdaterte klimastrategi ønsker Oslo kommune en forskningsbasert vurdering av potensialet for energisparing og reduksjon av klimagassutslipp fra energibruk i bygningsmassen framover mot 2040.

Bygg som allerede finnes i dag, vil utgjøre en stor andel av bygningsmassen i mange tiår fremover. Det er mulig å redusere energibruken i eksisterende bygg gjennom rehabilitering og energioppgradering. Nybygg bygget i fremtiden vil være langt mer energieffektive enn gjennomsnittlig eksisterende bygningsmasse. Men om disse bygges etter dagens krav, som passivhus eller nullutslippsbygg, har betydning for det samlede framtidige energibehovet. Hvilket omfang kan vi vente oss av framtidig nybygging og rehabilitering, og hva er det samlede potensialet for energisparing og reduksjon i klimagassutslipp fra energibruk i bygningsmassen i Oslo?

Ved bruk av en modell som simulerer bygningsmassens utvikling – gulvareal i ulike bygningstyper, andeler bygget etter eller rehabilitert til ulike tekniske standarder – prøver vi å forstå hvordan Oslos bygningsmasse vil utvikles mot 2040. Trender i bruk av ulike energibærere og omfang av lokal energiproduksjon brukes videre for å estimere det samlede behovet for levert energi til bygningsmassen. Ved bruk av utslippsintensiteter estimerer vi til slutt de totale klimagassutslippene fra energibruk i bygningsmassen i Oslo.

To alternative scenarioer studeres for å vurdere hvilken utvikling som kan forventes; et referansescenario der vi antar en fortsettelse av trender og videre utvikling med gradvis forbedret energitilstand på nybygg og rehabiliterte bygg, og et scenario som ser på hvilke tilleggsbesparelser i energibruk og klimagassutslipp som vil følge av en mer ambisiøs innfasing av nullutslippsbygg, mer energieffektive rehabiliterte bygg og større omfang av lokal energiproduksjon.

Estimerte utslipp av klimagasser fra energibruk avhenger i stor grad av hvilke utslippsintensiteter man velger å bruke for elektrisitet. I denne analysen presenterer vi tre alternative beregningsmetoder der vi antar a) norsk forbruksmiks, b) europeisk forbruksmiks og c) en marginalbetraktning der reduksjoner i norsk forbruk på lang sikt fører til at fossil elektrisitetsproduksjon i Europa reduseres.

Det er et stort potensial for energisparing og reduksjoner i klimagassutslipp ved ambisiøs innfasing av lokal energiproduksjon, nullutslippsbygg og mer energieffektive rehabiliterte bygg i Oslo.

Resultatene viser at selv om det samlede gulvarealet i bygningsmassen i Oslo er ventet å øke med 35 % i perioden 2009-2040, så er levert energi til bygningsmassen i referansescenarioet stabilt i perioden 2020-2040 på grunn av energieffektivisering gjennom nybygging og rehabilitering. Valg av utslippsintensitet har stor betydning for utslippenes størrelse og utvikling sammenliknet med referanseåret 2009. Resultatene viser imidlertid at det uavhengig av beregningsmetode er et stort potensial for energieffektivisering og utslippsreduksjoner. I det ambisiøse scenarioet er både total levert energi og klimagassutslipp fra energibruk i 2040 omtrent 20 % lavere enn i referansescenarioet.


Energies,
volume 12,
issue 5,

Is it possible to supply Norwegian apartment blocks with 4th generation district heating?

4th generation district heating represents the new generation of district heating systems. It reduces heat loss from the grid, enables better use of surplus heat and renewable energy sources, in addition to reducing the strain on the electricity grid. In short, 4th generation district heating is a sustainable solution for supplying heat to Zero Emission Neighbourhoods.

However, there are technical challenges that must be solved before it is introduced. One of them is to determine how low the supply temperature can be in different types of buildings so that we can identify the minimum district heating supply temperature. In our research, we evaluated the minimum supply temperature in Norwegian apartment blocks by improving the thermal envelope and reducing the temperature levels for the heating system. Our analysis focuses on whether the reduced supply temperature guarantees thermal comfort in the building.

Our project implied developing a database of building models representative of Norwegian apartment blocks. The building models consisted of eight age groups and three levels of energy performance. We performed simulations with two different temperature levels for the radiators typical for Norwegian buildings: 80/60 and 60/40 °C.

We found that reducing the supply temperature to the radiators from 80 to 60 °C is possible for buildings newer than from 1970, even for non-renovated buildings. For older buildings, an intermediate renovation, i.e. upgrading the windows, is necessary to maintain temperatures above the minimum acceptable temperature of 19 °C. Still, we highly recommend to perform a more ambitious renovation for these buildings to reduce the number of hours with significantly reduced indoor temperature compared to the setpoint temperature of 22 °C. In addition to reduce the heating demand and thus achieve energy savings, this will also ensure that the occupants are satisfied with their thermal environment.

The results can be used by district heating companies, building owners, contractors and consulting companies, in order to evaluate the introduction of 4th generation district heating in Norwegian apartment blocks. The models and Excel sheets with hourly results for energy need are available for partners and researchers within FME ZEN, so that they could be used for other purposes as well.

By Øystein Rønneseth


Gullbrekken, L., Grynning, S. & Gaarder, J. E. (2019) Thermal performance of insulated constructions – experimental studies
Buildings,
volume 9,
issue 2,

Abstract

Buildings that are designed to meet high-energy performance requirements, e.g., passive houses, require well-insulated building envelopes, with increased insulation thicknesses for roof, wall and floor structures. We investigate whether there are differences in the efficiency of thermal insulation materials at different moisture levels in the insulation and if there is a larger or smaller risk of natural convection in wood-fibre based insulation than in mineral wool.

The work has mainly been performed by use of laboratory measurements included permeability properties and full-scale measurements of thermal transmittance of mineral wool and wood-fibre insulated constructions. In addition, calculations have been used to calculate resulting effects on the thermal performance of constructions. Results showed that the thermal conductivity was unaffected by moisture in the hygroscopic range. The air permeability was found to be approximately 50% higher for the wood-fibre insulation compared to mineral wool insulation. Measurements showed that the largest U-values and Nusselt numbers were found for the wall configuration. Calculation of the U-value of walls showed that in order to achieve the same U-value for the wood-fibre insulated wall as the mineral wool, it is necessary to add 20 mm insulation to the 250 mm wall and approximately 30 mm for the 400 mm wall.


ZEN Report 13,
NTNU/SINTEF,

Abstract

(Scroll nedover for norsk sammendrag)

People play a key role in zero emission neighbourhoods. They are the ones designing and creating the neighbourhood, transforming and building it and finally using it when living and working there. People play different roles in that process – such as project owners, architects, construction workers, neighbours, and users. We summarize them under the word of stakeholders. They all have a stake in the project of ZEN even if their role and influence is different and changing under the development. Important is the way stakeholders are collaborating and how their knowledge, needs, and goals are negotiated and integrated in the project development. When asked for challenges to develop ZEN, interview partners emphasized the need for good collaboration between stakeholders. This is especially important as ZEN developments asks for more than standard neighbourhood developments: greenhouse gas emissions are an important planning and design factor, something that is new for many stakeholders, and tools and knowledge are missing for that. This memo will present tools in use for stakeholder engagement in the four ZEN pilot projects in Trondheim, Elverum, Steinkjer, and Sluppen. The mapping of tools was conducted in 2017 and 2018, and the analysis is based on qualitative interviews with involved stakeholders in the four pilot projects. The results show that the pilot projects use several tools on different spatial levels (city, neighbourhood and building level), and different tools are in use in different phases of development. The tools have different goals and involve different stakeholders, some are focusing on citizens, while others aim for engagement of professional stakeholders such as construction and energy companies. The concept of the ZEN toolbox is also introduced in this memo as the tools identified in the pilot projects are to be integrated in the further development of the toolbox. But before that, we need a better understanding of the applicability and benefit of the tools used for stakeholder engagement.

 

Norwegian Summary

Mennesker spiller en nøkkelrolle for å få til nullutslipps nabolag. De er de som planlegger og designer nabolaget, transformerer det, bygger det og til slutt bruker det. Mennesker spiller ulike roller i prosessen – som prosjekteiere, arkitekter, bygningsarbeidere, naboer og brukere. Vi kan samlet kalle dem stakeholdere. De har alle en eierandel i utviklingen av et ZEN område selv om deres rolle og innflytelse er forskjellig og endres under utviklingen av området. Det er særlig viktig hvordan stakeholderne samarbeider og hvordan deres kunnskap, behov og målsetninger blir ivaretatt og innlemmet i prosjektutviklingen. Når vi har spurt samtalepartnere fra ZEN pilotprosjektene hva som er viktig, har de understreket behovet for godt samarbeid mellom aktørene. Dette er spesielt viktig, fordi et ZEN område er noe mer enn vanlig områdeutvikling da fokus på klimagassutslipp må inn i plan og designfasen. Dette er nytt for mange av aktørene, og tilgangen til verktøy og kunnskap er fortsatt begrenset. Dette notatet vil presentere ulike verktøy og tiltak til bruk i dialog med stakeholderne i de fire FME ZEN pilotprosjekter Trondheim, Elverum, Steinkjer, og Bodø. Kartleggingen av verktøy er gjennomført i 2017 og 2018, og analysen er basert på kvalitative intervjuer med ulike aktører som er involvert i de fire pilotprosjektene. Resultatene viser at pilotprosjektene bruker forskjellige verktøy på ulike nivåer (by, nabolag, og bygningsnivå), og de bruker ulike verktøy i de aktuelle faser av utviklingen. Verktøyene har forskjellige mål og involvere ulike interessenter. Noen fokuserer på innbyggerne, mens andre retter seg mot profesjonelle aktører som for eksempel bygg og anleggsbransjen og energiselskapene. Konseptet med en ZEN verktøykasse er også innført i dette notatet, fordi de suksessfulle verktøyene som identifiseres i pilotprosjektene skal integreres på et senere tidspunkt i verktøykassen. Verktøykassen skal hjelpe andre utviklingsprosjekt på områdenivå til å ta de riktige valg i framtiden. Før vi kommer så langt trenger vi en bedre forståelse av anvendbarheten til de verktøyene som i dag finnes for å opprette en god dialog med de ulike stakeholderne.


Wiik, M. K., Fufa, S. M., Baer, D., Sartori, I. & Andresen, I (2018) The ZEN definition – a guideline for the ZEN pilot areas. Version 1.0
ZEN Report 11,
NTNU/SINTEF,

Abstract

The objective of this report is to provide a guideline for how the assessment criteria and key performance indicators (KPIs) covered under each category of the ZEN definition (GHG emissions, energy, power/load, mobility, economy and spatial qualities) may be assessed and followed up in ZEN pilot projects. The guidelines explain relevant evaluation methodologies, focusing on what types of data that could be used to access the criteria and KPIs, how these data could be collected, and how the fulfilment of the KPIs could be documented. Furthermore, the guidelines illustrate briefly the ZEN pilot projects and main challenges identified in their development. The target group of the ZEN definition guideline is the different actors involved in ZEN pilot projects and other interested parties in the field. This first version of the ZEN guideline report highlights the limitations and scope for further work, which will be addressed in future editions of the ZEN definition report.

 

Sammendrag

Hensikten med denne rapporten er å gi en veiledning til hvordan de ulike vurderingskriteriene og nøkkelindikatorene i ZEN definisjonen (klimagassutslipp, energi, effekt, mobilitet, økonomi, og stedskvaliteter) kan vurderes og følges opp i ZEN pilotprosjekter. Rapporten gir en beskrivelse av relevante evalueringsmetoder, og gir en oversikt over data som er nødvendig for å gjøre evalueringene. Videre gir rapporten en kort beskrivelse av pilotområdene i ZEN, med tilhørende hovedutfordringer. Målgruppen for veilederen er aktører som er involvert i planlegging og utvikling av ZEN pilotområder, samt andre som er interessert i dette området. Denne første versjonen av en veileder for ZEN pilotområder viser også begrensninger og utfordringer mht. til videre arbeid, som vil bli adressert i fremtidige utgaver av rapporten.

 

 


Lausselet, C., Borgnes V., Ager-Wick Ellingsen, L., Hammer Strømman, A. & Brattebø H. (2019) Life-cycle assessment methodology to assess zero emission neighboorhood concept
ZEN Report 12,
NTNU/SINTEF,

Abstract

Buildings represent a critical piece of a low-carbon future and their long lifetime necessitates urgent adoption of state-of-the-art performance standards to avoid significant lock-in risk. So far, life-cycle assessment (LCA) studies have assessed buildings (conventional and Zero Emission Building (ZEB)), mobility and energy systems mainly individually. Yet, these elements are closely linked, and to assess the nexus of housing, mobility, and energy associated with human settlements by aiming for Zero Emission Neighborhoods (ZENs) gives a unique chance to contribute to climate change mitigation. ZEBs and ZENs are likely to be critical components in a future climate change mitigation policy.

This study addresses the challenge of how to use LCA when implementing such a policy, in line also with the introduction of the more stringent Energy Performance of Buildings Directive in 2010 that requires new buildings to be built with nearly ZEB standards by the end of 2020. The specific aims of this report are fourfold. First, to develop and apply an LCA model to support the evaluation of ZEN design concepts with respect to greenhouse gas (GHG) emissions and other potential environmental impacts. Second, to clarify important contributing factors as well as revealing criticalities and sensitivities for GHG emission reductions and environmental performance of such ZEN design concepts. Third, to establish a model basis for other LCA studies on a neighbourhood scale, in terms of a high-quality modelling approach regarding consistency, transparency, and flexibility. Fourth, to apply our model on two cases; a hypothetical case of a neighbourhood consisting of single family house of passive house standard and on Zero Emission Village Bergen (ZVB).

For the first case, the neighbourhood consists of single-family houses built according to the Norwegian passive house standard. We designed four scenarios where we tested the impact of the house sizes, household size, energy used and produced in the buildings, and mobility patterns. Also, we ran our scenarios with different levels of decarbonization of the electricity mix over a time period of 60 years.

Our results show the importance of the operational phases of both building and mobility at year 1, and its decline over time induced by the decarbonization of the electricity mix. In year 60, embodied emissions are then responsible for the majority of the emissions when the electricity mix is decarbonized. The most important contributing factors have been identified as the operational phases of the Building and Mobility subsystems when the carbon intensity of the electricity mix is high, and as the embodied emissions in materials when the carbon intensity of the electricity mix becomes low. A reduction of the following factors has been identified as beneficial for the overall GHG emissions of a ZEN: (1) building floor area by house either/or by inhabitants, (2) passenger cars travel distances by household, which can be achieved by several means; e.g. commuting with public transport and/or by carpooling initiatives, (3) energy use in the buildings, which is reduced by the use of the passive house standard, and (4) carbon intensity of the electricity mix.

The second case – ZVB – consists of residential and non-residential buildings, with a total area of 91 891 m2; 695 dwellings and 1 340 inhabitants. The total emissions associated with the physical elements (buildings, mobility, open spaces, networks and on-site energy) and the life cycle stages (A1-A3, B4 and B6) resulted in a total of 117 kton CO2-eq over the lifetime. This equals 1.5 ton CO2-eq/capita/year and 21.2 kg CO2-eq/m2/year, referring to heated building floor area and as yearly average emissions over the 60 year analysis period. The emissions are distributed between the elements and life cycle stages. Buildings stand for the majority of the total emissions, accounting for about 52% of the total emissions over the lifetime. The mobility is the second most contributing element, responsible for 40% of the total emissions. The emissions from the networks and open spaces constitute only 2.3% together. A sensitivity analysis showed the emission intensity for electricity and the assumption of allocating emissions from waste incineration to the waste management system rather than to district heat to have a considerable impact on the results. If an EU28+NO electricity production mix is used instead of the Norwegian electricity production mix, total emissions over the 60 years analysis period will increase with 12.5%. This is despite the fact that also negative emissions from the on-site electricity production will be larger, due to the significant increase in emissions from electricity consumed in mobility. If the emissions from waste incineration is not allocated to the district heating production, the total emissions are decreased with 25.3%. Hence, this is a most critical assumption in the LCA model.

The most important contributing factors have been identified as the operational phases of the Building and Mobility subsystems when the carbon intensity of the electricity mix is high, and as the embodied emissions in materials when the carbon intensity of the electricity mix becomes low. A reduction of the following factors have been identified as beneficial for the overall GHG emissions of a ZEN: (1) building floor area by house or by inhabitants, (2) passenger cars travel distances by household, which can be achieved by several means; e.g. commuting with public transport and/or by carpooling initiatives, (3) energy use in the buildings, which is reduced by the use of the passive house standard, and (4) carbon intensity of the electricity mix.

Introducing passive house standards on buildings has the potential to drastically decrease the overall CO2-eq emissions of a ZEB, but also of a ZEN; up to by 191% when assuming an average European electricity mix. Yet, by using a highly decarbonized electricity mix, such as is the case in Norway, the decrease is much lower, around 12%.

Also, we found the choice of the functional unit to be decisive for the conclusion of the study. When conducting LCAs on a neighbourhood scale, we thus argue for the use of a primary functional unit “per neighbourhood”, and a second “per person”. The use of a “per m2 floor area” unit is misleading as it does not give credits for reducing the total built floor area.

All these findings demonstrate that the model is capable of long-term analyses of both homogenous and complex neighbourhoods, and provides a detailed understanding of possible future development of the different elements of the neighbourhood and their GHG emissions.

This report is a part of FME ZEN Work Package 1 Analytic framework for design and planning of zero emission neighbourhoods (ZEN). The goal for WP 1 is to develop definitions, targets and benchmarking for ZEN, based on customized indicators and quantitative and qualitative data. Additionally, an LCA methodology for energy and emissions at neighbourhood scale is developed, as well as a citizen-centred architectural and urban toolbox for design and planning of ZEN.


Energy and Buildings,
volumes 188-189,
pages 84-97,

Abstract

This paper explores the most influential aspects regarding the environmental and economic performance of zero-energy and zero-emission buildings and proposes a pathway for transition in building solutions. A representative zero-energy office building in Norway is investigated with alternative design solutions to achieve zero-emission status i.e., the extensive use of locally generated energy through photovoltaic (PV) panels and the use of materials with low embodied emissions, such as low-carbon concrete and wood. A life cycle environmental and economic assessment is performed to evaluate specific indicators during the building life cycle: cumulative energy (CED), global warming potential (GWP), and equivalent annual cost (EAC).

The extensive use of PV panels was most effective in lowering the operational energy because it reduced the CED by about 30% compared to the building as-built. However, the extensive use of wood in the construction contributed the most to GWP reduction, with around 30% decrease compared to the building as-built. Finally, the differences in EAC were interestingly insignificant among the alternatives, with the investment costs dominating the EAC for all designs examined.

The findings of this paper emphasise that a full compensation of the life cycle GHG emissions from materials is difficult to achieve through renewable energy, even with extensive use of PV panels, especially in a low-carbon grid situation as in Norway. A pathway strategy from zero-energy towards zero-emission buildings must therefore strongly focus on the materials’ embodied energy and emissions because low operational energy demand is already a regulatory priority in most countries.


Urban Planning,
volume 4,

Abstract

This article sets out to describe the role of aesthetics in citizen dialogues during the upgrading of a local swimming pool in Hammarkullen, Gothenburg. The swimming pool became an important project because of its role in a larger neighbourhood renovation project that allowed the municipality to focus on citizen engagement and inclusion. The engagement process showed the importance of the local swimming pool for a marginalized group of women of Somali origin, and a decision was made to keep the swimming pool instead of demolishing it. This led to collaboration between project coordinators, the Public Art Agency, an artist and an architect. Individual qualitative interviews focusing on storytelling were undertaken with key stakeholders.

The findings show that aesthetic quality mediated the communicative processes between project coordinators and citizens. Art in public space is more than just aesthetics or something to look at; art provokes a wide variety of responses and artists use a variety of means to engage with their public and creating dialogue. Yet the project managers failed to consider the creative process of the architect and her perspective on aesthetic quality and building functionality.

Stakeholders take different stances to whether aesthetic quality can be a way of grounding, communicating and evolving, or whether it is a matter of beauty where the artist or architect takes the lead. While the project coordinators affirm sameness, different understandings of aesthetic quality actively negotiate social differences. Inability to consider creative practices’ work processes in relation to citizen dialogue can result in conflicts between art, architecture and governance during the transformation of a neighbourhood.


Applied Energy,
volume 237,
pages 500-518,

Abstract

The building energy flexibility potential of a Norwegian single-family detached house is investigated using predictive rule-based control (PRBC) and building performance simulation (using IDA ICE). Norwegian timber buildings are lightweight and four different insulation levels are considered. Both on-off and modulating air-source heat pumps are analyzed and compared to direct electric heating which is the most common heating system for Norwegian residential buildings. A detailed model for both the heat pump system and the building is implemented, a level of detail not found in previous research on building energy flexibility.

The three PRBC investigated have the following objectives: reduce energy costs for heating, reduce annual CO2eq. emissions and reduce energy use for heating during peak hours. This last objective is probably the most strategic in the Norwegian context where cheap electricity is mainly produced by hydropower. The results show that the price-based control does not generate cost savings because lower electricity prices are outweighed by the increase in electricity use for heating. The implemented price-based control would create cost savings in electricity markets with higher daily fluctuations in electricity prices, such as Denmark. For the same reasons, the carbon-based control cannot reduce the yearly CO2eq. emissions due to limited daily fluctuations in the average CO2eq. intensity of the Norwegian electricity mix. On the contrary, the PRBC that reduces the energy use for heating during peak hours turns out to be very efficient, especially for direct electric heating. For air-source heat pumps, the control of the heat pump system is complex and reduces the performance of the three PRBC.

Therefore, results suggest that a heat pump system should be modeled with enough detail for a proper assessment of the building energy flexibility. First, by varying temperature set-points there is a clear interaction between the prioritization of domestic hot water and the control of auxiliary heaters which increases energy use significantly. Second, the hysteresis of the heat pump control and the minimum cycle duration prevent the heat pump from stopping immediately after the PRBC requires it. Finally, the paper shows that the influence of thermal zoning, investigated here by cold bedrooms with closed doors, has a limited impact on the building energy flexibility potential and the risk of opening bedroom windows.


Applied Energy,
volume 238,
pages 696-720,

Future weather files for a robust design of buildings and neighborhoods against climate change

In the last decade, some of the warmest years on record have been experienced. Failure in climate change adaptation can lead to costly short- and long-term issues, such as blackouts due to energy supply disruption. These problems partly are arising from the fact that existing buildings are not designed for atypical conditions, and their expected performance is based on most-likely conditions. Building performance simulation (BPS) empowers designers to evaluate a proposed design under the probable climate conditions that a building will face during its lifetime. This work aims at answering the question: what type of future weather files enable building engineers and designers to more reliably test robustness of their designs against climate change.
Extreme weather files are needed for a robust design in building and urban scales

The standardized weather files of today are a single-year of typical weather data that represent typical regional climate conditions based on historical data. One of the main disadvantages of this method on climate change impact assessment is its averaging nature. The averaging process can result in missing extreme values and therefore shows how systems designed taking into consideration only typical conditions could quickly become a costly mistake (due to under-dimensioning).
This study provides an overview of the major approaches for creating future weather data sets. For the first time, the effects of using major available approaches for generating future weather files are studied on the calculation of energy performance of buildings. The building models were simulated in isolation and combined to create a virtual neighborhood.

The study investigates the possibility and importance of using extreme weather years in BPS at both the building and neighborhood scales. This will allow understanding the magnitude of the risk induced at large scale by not taking into account possible future climate extremes.

The analysis of the virtual neighborhood revealed that the peak electric power demand for the neighborhood can increase up to 16.8% under extreme conditions in comparison to the typical conditions. These results underline the importance of considering extreme conditions in studying the impacts of climate change on larger spatial scales (e.g. urban and city scales) and preparing urban energy systems for such future conditions.

In conclusion, our work provided further evidence that proper weather data sets based on high resolution data from climate models and several climate scenarios, including extreme conditions, are required to empower building engineers and architects to test their design solutions under future climate uncertainties.

By Amin Moazamia


ZEN Memo 11,
NTNU/SINTEF,

This aim of study connected to this report is to answer the following research question: «What are the key drivers of success and failure when it comes to public private collaboration in a zero-emission context?» In this regard, a narrative literature review is conducted to find relevant scientific articles and cases. The cases are studied and results are obtained. Results show various success factors and barriers in public private collaboration in the context of zero emission neighborhood. The results are presented.

Anandasivakumar Ekambaram

Building and Environment,
volume 149,
pages 446-457 ,

Abstract

Designing a zero emission neighborhood (ZEN) from an energy point of view, has the benefit of distributing loads over time by creating a mosaic of buildings which individually may not have a zero emission balance, but reach it as an ensemble. Responsive building envelopes (RBEs) are expected to play an important role in the design of ZENs and future smart sustainable cities. RBEs are useful to optimize the balance between several energy flows at single- and multi building scale, as well as to actively manage both on-site renewable- and purchased energy in addition to improving user experience and indoor comfort by providing an interactive interface with the outdoors.

This article provides a review of the potential and the requirements associated with using RBEs to manage complex interactions between buildings, clusters of buildings and utility grids. A six-step pathway for the implementation of RBEs in ZEN-like projects are proposed. The six steps are related to identifying; purpose of response, scale and interdependency, functionality, trigger and control, interactions and finally to identifying technical solutions. The proposed process emphasizes the importance of defining specific information such as the responsive goal hierarchies, the scale of the responses in relation to their purpose, and the importance of the aesthetic expression to foster positive user experience.

 


ZEN Report 10,
NTNU/SINTEF,

Summary

This report on the pilot projects of the Research Centre on Zero Emission Neighbourhoods in Smart Cities will give the reader an overview of eight pilot projects of the Centre, focusing on the challenges to develop or transform the pilot areas into Zero Emission Neighbourhoods.

The objective of the ZEN Centre is to develop products and solutions that will lead to the realization of sustainable neighbourhoods with zero greenhouse gas emissions. These solutions will be tested in the eight real life pilot projects in Norwegian municipalities. When searching for the best solutions, we first need to map the pilot projects and the challenges they are facing on the way to become sustainable zero emission neighbourhoods. This report will therefore serve as an introduction to the eight pilot projects to help the ZEN partners to develop an understanding for the pilot projects and their challenges, as a base for further research and cooperation.

This report will start with a short introduction of the Research Centre and present a working definition for a Zero Emission Neighbourhood. Each of the eight pilot projects are described in detail by their individual characteristics regarding location, stakeholders, goals, measures, status of project development, and challenges. Challenges were identified through qualitative interviews with stakeholders of the pilot projects. These interviews were conducted in 2017.

A systematic documentation of the process and challenges to develop ZENs will help to identify the success factors and best practices that are needed for planning and developing ZENs. This enables the involved partners to learn from the first pilot projects, and to transfer solutions to other neighbourhood developments. This report provides a foundation for further follow-up, documentation, and analysis.

 

Norwegian Summary

Denne rapporten vil gi leseren en oversikt over de åtte pilotprosjektene i ZEN Forskningssenter, med fokus på utfordringene som ligger i å utvikle og transformere pilotprosjektene til nullutslippsområder.

Målet med forskningssenteret ZEN er å utvikle produkter og løsninger som vil føre til realisering av bærekraftige nabolag med null klimagassutslipp. Disse løsningene blir testet i åtte pilotprosjekter i norske kommuner. Når vi søker etter de beste løsningene, er det viktig å ha kartlagt pilotprosjektene med tanke på de utfordringene de står overfor med tanke på å oppnå bærekraftige nabolag med null utslipp av klimagasser. Denne rapporten vil derfor fungere som en introduksjon til de åtte pilotprosjektene og skal hjelpe ZEN-partnerne til å utvikle en felles forståelse for pilotprosjektene og deres utfordringer som grunnlag for videre forskning og samarbeid.

Rapporten starter med en kort introduksjon av forskningssenteret og en arbeidsdefinisjon av hva som legges i ZEN. Hvert av de åtte pilotprosjektene er beskrevet i detalj med deres individuelle egenskaper som plassering, interessenter, mål, tiltak, status for prosjektutvikling og utfordringer. Utfordringene ble identifisert gjennom kvalitative intervjuer med de involverte aktørene i pilotprosjektene, mange av dem er ZEN partnere. Disse intervjuene ble gjennomført i 2017.

En systematisk dokumentasjon av prosessen og utfordringene med å utvikle ZENs vil bidra til å identifisere suksessfaktorer og beste praksis for å planlegge og utvikle ZEN. Dette gjør det mulig for de involverte partnerne å lære fra de første pilotprosjektene og overføre løsninger til andre byutviklingsprosjekt senere. Denne rapporten danner grunnlaget for videre oppfølging, dokumentasjon og analyse.


ZEN Report 8,
NTNU/SINTEF,

Abstract

This report is a part of Work Package 4 Energy Flexible Neighbourhoods. The goal for WP 4 is to develop knowledge, technologies and solutions for design and operation of energy flexible neighbourhoods.

4th generation district heating is evaluated as a sustainable solution for covering the heating demand in Zero Emission Neighbourhoods and reducing the strain on the electricity grid. There are, however, some technical challenges that must be solved before it is introduced. One of them is to determine how low the supply temperature could be in different building types, which again will determine the minimum district heating supply temperature. This report is evaluating the minimum supply temperature in Norwegian apartment blocks based on effects of improving the thermal envelope and reducing the temperature levels for the heating system. The analysis is based on building simulation and focuses on whether the reduced supply temperature guarantees the comfort in the building, considering the coldest room with a heating setpoint of 22 °C and a minimum acceptable indoor temperature of 19,0 °C.

The simulated buildings are based on the data available from the IEE project Tabula. Generic models representative for Norwegian apartment blocks have been developed in IDA ICE. They consist of eight age classes and three levels of energy performance: • Prior to 1956, from 1956-1970, 1971-1980, 1981-1990, 1991-2000, 2001-2010, 2011-2020 and 2020 →. • Original, intermediate renovation and standard renovation For the intermediate renovation level, it is only the windows and infiltration rates that have been changed. Tabula also includes an ambitious renovation, but this has not been modelled as the results are expected to be similar to those for the newest age class. Simulations are performed with two different dimensioning temperature levels for the radiators typical for Norwegian buildings; 80/60 and 60/40 °C. The results showed that it is possible to reduce the supply temperature to the radiators from 80 to 60 °C for buildings from 1971-80 and all newer age classes, even for the non-renovated buildings. This is based on a minimum acceptable indoor temperature of 19.0 °C (according to the Norwegian building regulations, TEK). For the older age classes, an acceptable indoor temperature is not achieved for the non-renovated buildings when reducing the supply temperature. Although it is sufficient to perform the intermediate renovation to maintain temperatures above 19 °C, it is highly recommended to perform the standard renovation for these age classes to reduce the number of hours with a significantly reduced indoor temperature compared to the setpoint temperature. In addition to reduce the heating demand and thus lead to energy savings, this will also ensure that the occupants are satisfied with their thermal environment. It is important to note that the conclusions would be different if the minimum acceptable temperature was set higher, for instance at 20 or 21 °C. The results can be used by district heating companies, building owners, contractors and consulting companies in order to evaluate the introduction of 4th generation district heating in Norwegian apartment blocks. Both the models and excel sheets with hourly results are available for partners and researchers within FME ZEN.


ZEN Report 9,
NTNU/SINTEF,

Abstract

eTransport is a linear optimization tool for evaluating energy supply alternatives for building areas. This report describes an improved, more realistic district heating (DH) module that has been developed for eTransport. The new module includes several improvements as compared to the previous module:

  • Varying mass flow that depends on the heat load, as opposed to constant mass flow. 
  • Pressure included as a variable, with certain limits for minimum pressure and minimum pressure drop at the loads. 
  • Calculation of pumping power is included in the module, and pumping power due to pressure losses in pipes and at loads is included in the objective function 
  • A more realistic calculation of heat losses included, and the heat losses are included in the heat load 
  • The module allows supply flow to both directions in a pipe; a property which is relevant when more heat sources are present in a DH grid. This feature is however yet to be tested properly.

The report presents the main equations required for mathematical description of a district heating system are presented, followed by the approach taken for linear representation of these equations, required for eTransport. The report includes a brief evaluation of the module using a simple test network, and discusses the simplifications and limitations of the present module, giving suggestions for further improvements.

Sammendrag

Fjernvarme er en viktig muliggjørende teknologi i det grønne skiftet. Fjernvarme kan nyttiggjøre energi som ellers ville gått til spille, slik som gjenvunnet varme fra avfallsforbrenning og industriprosesser; eller mindre spillvarmekilder tilgjengelig i byer, slik som datasentre og store matvarebutikker. Ved hjelp av et fjernvarmesystem kan slike kilder anvendes til oppvarming av boliger og næringsbygg. Med et godt samspill med kraftnettet bidrar fjernvarme i tettbygde strøk til å avlaste kraftnettet og tilgjengeliggjøring elektrisitet til andre formål enn til oppvarming. Bygging av et fjernvarmesystem krever store investeringer i startfasen, og dermed er det viktig å vite hvilke energikilder man bør velge til et gitt område for å minimere tilbakebetalingstiden. Det er derfor vanlig å bruke planleggingsverktøy for sammenlikning av ulike energiforsyningsalternativer til området. eTransport er et slikt verktøy, lagd av SINTEF Energi i 2006. Verktøyet skal oppgraderes og videreutvikles i FME ZEN. eTransport omfatter flere energibærere, og finner den optimale måten til å drifte energisystemet, samt en optimal ekspansjonsplan i et geografisk definert område. I mange tilfeller vil det være konkurransen mellom ulike energibærere: behovet for oppvarming kan dekkes av elektrisitet eller av et fjernvarmesystem og varme kan genereres fra kilder. eTransport beregner de årlige driftskostnadene for ulike energisystemdesign, og sender disse til en investeringsmodell som finner en optimal ekspansjonsplan.

Denne rapporten beskriver en oppgradering av fjernvarmemodulen i eTransport. I den tidligere versjonen av eTransport var modulen for beskrivelse av et fjernvarmesystem svært forenklet. Den oppgraderte modulen er mer realistisk i forhold til beregning av massestrøm, varmetap, trykktap og pumpearbeid. Modulen tillater dessuten forsyning av varme i begge retninger i et rør, noe som kan være aktuelt i et varmenett som utnytter flere, distribuerte varmekilder. eTransport et lineært optimalisverktøy, og rapporten presenterer den valgte tilnærmingen for lineær formulering av de viktigste likningene for beskrivelse av et fjernvarmesystem.


Conference proceedings,
2018 International Conference on Information and Communication Technology Convergence (ICTC) ,

Abstract

A huge volume of data are being generated from multiple sources, including smart cities, the IoT devices, scientific modeling, or different big data simulations; but also from users’ daily activities. These daily new data are added to historical repositories, providing the huge and complex universe of the digital data. Recently, the Fog-to-Cloud (F2C) data management architecture is envisioned to handle all big data complexities, from IoT devices (the closest layer to the users) to cloud technologies (the farthest layer to the IoT devices), as well as different data phases from creation to usage from fog to cloud scenario. Moreover, the F2C data management architecture can have several benefits from the combined advantages of fog (distributed) and cloud (centralized) technologies including reducing network traffic, reducing latencies drastically while improving security.
In this paper, we have several novel contributions. First, we described the previous studies of the Zero Emission Buildings (ZEB) in the context of the data flow and movement architecture. Second, we have proposed Zero Emission Neighbourhoods (ZEN) data management architecture for smart city scenarios based on a distributed hierarchical F2C data management. Indeed, we used the 6Vs big data challenges (Volume, Variety, Velocity, Variability, Veracity, and Value) for evaluating the data management architectures (including ZEB and ZEN). The result of the evaluation shows that our proposed ZEN data management architecture can address 6Vs challenges and is able to manage the data lifecycle from its production up to its usage.

Tereshchenko, T. & Nord, N. (2018) Future Trends in District Heating Development
Current Sustainable/Renewable Energy Reports,
volume 5 ,
172-180,

Purpose of Review

This article describes challenges that should be overcome towards implementation of low-temperature district heating (LTDH). The trends in development, operational issues, and legislative framework were revised.

Recent Findings

The new substation design with solutions to avoid legionella bacteria issue, improved network topology and control strategies, opportunities of LTDH for buildings under various renovation stages and construction year were identified as the most crucial for the transition to 4th generation district heating (DH). Importance of heat load aggregation to avoid peak load issue in the areas with low-energy buildings (LEB) and solutions for transition from high temperature to low temperatures in the DH network have been shown

Findings

The findings indicate that there is a huge potential for achieving low-carbon society and improvement in energy efficiency under transition to LTDH. The solutions for transition from high-temperature DH to LTDH exist; however, they need good policies and market availability to be implemented.


Sustainability,
volume 10,
pages 1-19,

Abstract

The building industry is responsible for approximately 40% of energy consumption and 36% of greenhouse gas emissions in the European Union (EU). The most efficient way of reducing a building’s environmental impact is addressing it in the design stage. Here, design freedom is the greatest, but uncertainty is high and there is a nearly limitless number of design options.

Based on experiences with zero emission buildings (ZEB) and zero emission neighbourhoods (ZEN), a mapping review has been conducted to analyse how parametric life cycle assessment (LCA) and algorithms have been used to address neighbourhoods, buildings, and construction materials. Results have identified a general gap of knowledge regarding the use of parametric LCA models for decision-support purposes, demonstrated by the substantial focus on analytical methods compared to procedural methods. Implications for the evolution from ZEB to ZEN are twofold: (i) an integrated approach with multiple tools and methods is required, and (ii) further development of algorithms in the tool are needed to address complexity, sensitivity, and uncertainty.

This study is expected to foster the development of algorithmic approaches to improve the ZEB tool as a decision-support tool. Further research should address the key questions of when and how


Rasmussen, F.N., Malmqvist, T., Moncaster, A., Houlihan-Wiberg, A. & Birgirsdottir, H. (2018) Analysing methodological choices in calculations of embodied energy and GHG emissions from buildings
Energy and Buildings,
volume 158,
pages 1487-1498,

Abstract

The importance of embodied energy and embodied greenhouse gas emissions (EEG) from buildings is gaining increased interest within building sector initiatives and on a regulatory level. In spite of recent harmonisation efforts, reported results of EEG from building case studies display large variations in numerical results due to variations in the chosen indicators, data sources and both temporal and physical boundaries.

The aim of this paper is to add value to existing EEG research knowledge by systematically explaining and analysing the methodological implications of the quantitative results obtained, thus providing a framework for reinterpretation and more effective comparison. The collection of over 80 international case studies developed within the International Energy Agency’s EBC Annex 57 research programme is used as the quantitative foundation to present a comprehensive analysis of the multiple interacting methodological parameters. The analysis of methodological parameters is structured by the stepwise methodological choices made in the building EEG assessment practice. Each of six assessment process steps involves one or more methodological choices relevant to the EEG results, and the combination potentials between these many parameters signifies a multitude of ways in which the outcome of EEG studies are affected.


Malmqvist, T., Nehasilova, M., Moncaster, A., Birgisdottir, H., Rasmussen, F.N, Houlihan-Wiberg, A. & Potting, (2018) Design and construction strategies for reducing embodied impacts from buildings – Case study analysis
Energy and Buildings,
volume 166,
pages 35-47,

Abstract

The dominance of operational energy and related greenhouse gas (GHG) emissions of most existing buildings is decreasing in new construction, when primary fossil energy of building operation decreases as result of the implementation of energy efficiency measures as well as a decarbonisation of national energy mixes. Stakeholders therefore have a growing interest in understanding the possibilities for reducing embodied impacts in buildings. In the IEA EBC project ‘Annex 57’ a broad call for case studies was launched with the aim to identify design strategies for reducing embodied energy and GHG emissions (EEG) from buildings.

The aim of this paper is to identify and provide a collected and comprehensive overview of quantitative reduction potentials of the particular EEG reduction strategies which should be considered by the stakeholders engaged in, and with the capacity to influence the outcome of, individual building projects. This is done by a systematic analysis of the Annex 57 case study collection as well as additional scientific literature. While it should be noted that the actual EEG savings at building level illustrated in this collection of studies are only applicable to each specific case, importantly this multiple cross-case analysis has provided rigorous evidence of the considerable potential to reduce embodied impacts in the design and construction of new and refurbished buildings.


Energy Research & Social Science,
volume 39,
pages 226-233 ,

Abstract

The Trondheim Living Lab is a detached single-family zero emission building (ZEB) that is planned to reach a zero-emission balance over the course of its estimated 60-year lifetime. This is achieved by a broad variety of technical strategies such as passive and active energy design and efficient installations, as well as calculations of embodied emissions. In qualitative experiments conducted between September 2015 and April 2016 six different groups lived in the house for 25 days each. Based on direct observation (mainly through sensors registering temperature, humidity, CO2 levels and energy use), participant observation and interviews before, during and after the stay, the paper analyses the unfolding domestication of the building along three dimensions; practical, symbolic and cognitive.

The paper provides an account of which expected or unexpected occupant actions matter in which way for the zero emission ambitions of the building. Moreover, by studying the way in which the six groups within the three different categories student, family and elderly experienced living in this demonstration building this paper contributes a more detailed understanding of the overall acceptance of a ZEB in Norway.


Kristjansdottir, T.F., Houlihan-Wiberg, A., Andresen, I., Georges, L., Heeren, N., Good, C.S. & Brattebø, H. (2018) Is a net life cycle balance for energy and materials achievable for a zero emission single-family building in Norway?
Energy and Buildings,
volume 168,
pages 457-469 ,

Abstract

In this study, the objective is to redesign a previous concept for a single-family Zero greenhouse gas Emission Building (ZEB). The concept is redesigned based on comparing greenhouse gas (GHG) emission loads and compensation from different design solutions applied in Norwegian single-family ZEB pilot buildings and selected sensitivity studies. The objective is to see if a previously developed ZEB model (2011) can be redesigned to achieve a life cycle energy and material emission balance (ZEB-OM), which previously was not achieved.

Five different design parameters are evaluated: area efficiency, embodied emissions in the envelope, insulation thickness, heating systems and different roof forms with respect to the photovoltaic area. Embodied emissions reductions were possible in the ground foundation, from around 1 kg CO2/m2 to 0.6 kg CO2/m2 per year. Both models are able to compensate for all operational emissions. The new model is in addition able to compensate for 60% of embodied emissions, whereas the previous model only could compensate for 5%. The new model does not reach the life cycle energy and material balance. The paper presents and discusses different approaches for achieving the ZEB-OM balance. Further concept model optimization is needed.


Junker, R.G., Azar, A.G., Lopes, R., Lindberg, K.B., Reynders, G., Relan, R. & Madsen, H. (2018) Characterizing the energy flexibility of buildings and districts
Applied Energy,
volume 225,
pages 175-182,

Abstract

The large penetration rate of renewable energy sources leads to challenges in planning and controlling the energy production, transmission, and distribution in power systems. A potential solution is found in a paradigm shift from traditional supply control to demand control. To address such changes, a first step lays in a formal and robust characterization of the energy flexibility on the demand side. The most common way to characterize the energy flexibility is by considering it as a static function at every time instant. The validity of this approach is questionable because energy-based systems are never at steady-state. Therefore, in this paper, a novel methodology to characterize the energy flexibility as a dynamic function is proposed, which is titled as the Flexibility Function.

The Flexibility Function brings new possibilities for enabling the grid operators or other operators to control the demand through the use of penalty signals (e.g., price, CO2, etc.). For instance, CO2-based controllers can be used to accelerate the transition to a fossil-free society. Contrary to previous static approaches to quantify Energy Flexibility, the dynamic nature of the Flexibility Function enables a Flexibility Index, which describes to which extent a building is able to respond to the grid’s need for flexibility. In order to validate the proposed methodologies, a case study is presented, demonstrating how different Flexibility Functions enable the utilization of the flexibility in different types of buildings, which are integrated with renewable energies.


Dziedzic, J.W., Yan, D. & Novakovic, V. (2018) Real Time Measurement of Dynamic Metabolic Factor (D-MET)
Conference proceedings,
Cold Climate HVAC 2018 ,

Abstract

The presented study describes developing a method for observing building occupants’ activity. Once their activity is registered, such data can be used to identify typical patterns in their behaviour. The collected information will support development of an occupant-behaviour-energy-related model in residential buildings. Data registration was done with the use of the Microsoft Kinect device as a depth registration camera. This research explores an innovative approach to investigating residents’ living and working habits. It supports the already existing thermal comfort models by delivering high resolution information about occupants’ activities. The obtained solution and its output will be used in the next stage of developing a dynamic metabolic rate (D-MET) model that will simulate the MET value. With proper data, it will be possible to estimate the real impact of occupants and their behaviour on energy consumption of buildings.


Dong, B., Kjærgaard, M.B., Simone, M.D., Gunay, H.B., O'Brien, W., Dafni, M., Dziedzic, J. & Zhao, J. (2018) Sensing and Data Acquisition
Conference proceedings,
Exploring Occupant Behavior in Buildings,
chapter 4,
pages 77-105,

Abstract

Occupant sensing and data acquisition are essential elements for occupant behavior research. A wide range of different types of sensors has been implemented to collect rich information on occupants and their interactions with the built environment, such as presence, actions, power consumption, etc. This information establishes a foundation to study the physiological, psychological, and social aspects of occupant behavior. This chapter summarizes existing occupancy and occupant behavior sensing and data acquisition technologies in terms of field applications, and develops nine performance metrics for their evaluation. The reviewed technologies focus on both occupants’ presence and interactions with the built environment, and are grouped into six major categories: image-based, threshold and mechanical, motion sensing, radio-based, human-in-the-loop, and consumption sensing. This chapter provides an overview and discussion of different current state-of-the-art and future sensing technologies for researchers.


Backe, S., Crespo del Granado, P., Pinel, D., Korpås, M., Tomasgard, A. & Lindberg, K.B. (2018) Towards Zero Emission Neighbourhoods: Implications for the Power System
Conference proceedings,
2018 15th International Conference on the European Energy Market - EEM ,

Abstract

This paper investigates the development of neighbourhoods with ambitious emission targets in the Nordic countries and their value for the power system. The targets relate to compensating for emissions in neighbourhoods through local low-carbon electricity and heat production. The first part of our analysis investigates local generation expansion with a neighbourhood perspective using a mixed integer linear programming model. The second part investigates the value of representative neighbourhoods with a country perspective using a generation and transmission capacity expansion model. When coupling the models, results indicate that neighbourhoods with co-generation of electricity and heat are most attractive for the power system in the Nordics, while neighbourhoods with solar PV provide most emission reduction.

M. K. Wiik, S. M. Fufa, J. Krogstie, D. Ahlers, A. Wyckmans, P. Driscoll, H. Brattebø, A. Gustavsen (2018) Zero emission neighbourhoods in smart cities: Definition, key performance indicators and assessment criteria: version 1.0. Bilingual version.
ZEN Report 7,
NTNU/SINTEF,

This document outlines the definition, key performance indicators (KPI) and assessment criteria for the Research Centre on Zero Emission Neighbourhoods in Smart Cities (ZEN research centre). This first version of the ZEN definition includes contributions from the ZEN partners. In total, around 50 people involved in the ZEN research centre have contributed to this document.

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Denne rapporten beskriver definisjonen, nøkkelindikatorer og vurderingskriterier som benyttes i forskningssenteret for nullutslippsområde i smarte byer (ZEN senteret). Dette er den første utgaven og inkluderer innspill og bidrag fra ZEN partnerne. Til sammen har omkring femti eksperter fra ZEN senteret bidratt til dette dokumentet. Rapporten foreligger både på engelsk og norsk.

M. K. Wiik, S. M. Fufa, J. Krogstie, D. Ahlers, A. Wyckmans, P. Driscoll, H. Brattebø, A. Gustavsen

Kolstad, M.L., Backe, S., Wolfgang, O. & Sartori, I. (2018) Software tools for local energy system operation and expansion
ZEN Report 6,
NTNU/SINTEF,

Abstract

This report describes existing software tools for analysing operation and expansion of local energy systems and is written in WP5 in the Research Centre on Zero Emission Neighbourhoods in Smart Cities (ZEN). WP5 in FME ZEN aims to develop and apply methodologies that identify the socioeconomic optimal operation and expansion of energy systems within demarked areas. The eTransport model is planned to be further developed and used to analyse pilot cases in ZEN. This report provides a brief description of the eTransport model and other alternative models found in the literature or used by partners in FME ZEN. The models are assessed based on their suitability to address the planned research tasks in FEM ZEN WP5. The report also includes a description of models developed for global and international analysis.

We are grateful for views and suggestions provided by Henrik Madsen (professor at DTU), and for comments provided by Anne Grete Hestnes (professor NTNU)

M. L. Kolstad, S. Backe, O. Wolfgang, I. Sartori

Justo-Alonso, M. (2018) Er det nok å åpne vinduet?
Geminibloggen,
26.07.2018,
further featured in no. of sources: 2,

Ett spørsmål klarer ikke arkitekter og ingeniører å bli enige om. Er det best å bare åpne vinduene om du vil lufte ut en bygning?

Maria Justo Alonso

ZEN Memo 5,
NTNU/SINTEF,

Dette dokumentet inneholder forslag til kriterier for hva som skal være krav og retningslinjer, samt roller og ansvar knyttet til å være et pilotprosjekt i forskingssenteret Zero Emission Neighbourhoods.

Inger Andresen

ZEN Memo 4,
NTNU/SINTEF,

Dette dokumentet inneholder forslag til kriterier for hva som skal være krav og retningslinjer, samt roller og ansvar knyttet til å være et CASE-prosjekt i forskingssenteret Zero Emission Neighbourhoods.

Inger Andresen

Sørensen, Å.L., Fredriksen, E., Walnum, H.T., Skeie, K.S. & Andresen, I. (2018) ZEN pilot survey – Initial plans for thermal and electrical use, generation, distribution and storage
ZEN Memo 3,
NTNU/SINTEF,

To develop zero emission neighbourhoods in smart cities, knowledge is needed in a number of areas. This pilot survey describes the initial plans for the ZEN pilot areas regarding thermal and electrical use, generation, distribution and storage.

Åse Lekang Sørensen, Eyvind Fredriksen, Harald Taxt Walnum, Kristian Stenerud Skeie, Inger Andresen

Sørensen, Å.L., Jiang, S., Torsæter, B.N. & Völler, S. (2018) Smart EV charging systems for zero emission neighbourhoods
ZEN Report 5,
NTNU/SINTEF,

Abstract

The increased use of electric vehicles (EVs) calls for new and innovative solutions for charging infrastructure. At the same time, it is desirable to improve the energy flexibility of neighbourhoods. This paper presents state-of-the-art for smart EV charging systems, with focus on Norway.

The aim of the study is to start investigating how smart EV charging systems can improve the energy flexibility in a Zero Emission Neighbourhood (ZEN). The intention is that the study will be useful when evaluating activities and technologies for the ZEN pilot areas.

The paper presents energy demand for EV charging and typical charging profiles. Further, it describes how charging stations can interact also with the energy need in buildings and neighbourhoods, local energy production and local electric and thermal energy storage. Examples of commercial smart EV charging systems are described.

The report lists some opportunities for testing smart EV charging in the ZEN pilot areas. Piloting of new technologies and solutions can provide more knowledge about smart EV charging systems, and how they can participate in matching energy loads in buildings and infrastructure with local electricity generation and energy storage.

Åse Lekang Sørensen, Shanshan Jiang, Bendik Nybakk Torsæter, Steve Völler