Publications

All publications from the ZEN Research Centre are financially supported by the Research Council of Norway through its funding scheme for Centres for Environment-friendly Energy Research (grant no. 257660).

Our latest scientific publications

Krohn Aasgård, Ellen (2020) Utforming av prissignal i kraftmarkedet
ZEN Memo 27,
SINTEF,

All our publications

Korsnes, Marius (2019) Wind and Solar Energy Transition in China
New York: Routledge,

Woods, R., Berker, T., Baer, D. & Bø, L. A. (2019) ZEN living labs definition, ideas, and examples
ZEN Report 18,
NTNU/SINTEF,

Popular summary in English:

(Scroll nedover for norsk sammendrag)

Living labs are user centred initiatives where knowledge production involves individuals or user groups
affected by sustainable transitions. The FME Research Centre on Zero Emission Neighbourhoods in
Smart Cities (ZEN) has chosen living labs to secure user engagement and as a framework for the
organisation of user involvement in pilot projects. The report presents three main elements, firstly the
ZEN understanding of what a living lab is and how it may be applied within a ZEN neighbourhood.
Secondly, it offers examples of living labs that have inspired the ZEN use of the living lab concept, and
thirdly, it provides insight into how user participation has already taken place within ZEN pilot
neighbourhoods.

Historical and current applications of living labs are presented in the report, underlining the potential of
using the ZEN living lab concept. A ZEN living lab is an open, inclusive space that supports user
engagement with ZEN pilot projects, bridging the gap between the social and technical context. A ZEN
living lab should function as a creative arena for knowledge exchange, between people, places, and
technology. An arena that should ideally highlight learning processes. The ZEN living lab concept
includes four main elements:

1. Representatives from the different user groups affected by the sustainable neighbourhood
transition proposed by ZEN.
2. A clearly defined geographical place.
3. A set of iterative activities.
4. An experimental format based on the challenges and needs of the neighbourhood.

The definition of zero emission neighbourhoods applied by the ZEN Centre implies technical solutions
to the reduction of energy use and CO2 emissions. This definition implies a target-based application of
the living lab methodology: the testing of technical solutions as a means to achieve innovations within
the construction industry or the energy sector. The ZEN living lab concept proposes as less target based
understanding of the pilot projects, because any application of the living lab concept should not lose
sight of the primary aim, which is engaging with the user groups who will be affected by the changes
implied by the introduction of zero emission technology. This should take place in an open and inclusive
process where the results may be learned from but not necessarily measured.

 

Norsk sammendrag:

Living labs er brukersentrerte tiltak som har mål om å involvere ulike individer eller brukergrupper i
tekniske eller bærekraftig endringer i samfunnet. The FME Research Centre on Zero Emission
Neighbourhoods in Smart Cities (ZEN) har valgt living labs som et format til å organisere og sikre
brukerengasjement i pilotprosjekter. Hovedformålene med bruk av living labs i ZEN-pilotprosjekter er
å øke forståelsen blant ulike brukergrupper for ZENs målsettinger og til å støtte arbeidet med å realisere
bærekraftige endringer. Rapporten presenterer ZEN-definisjonen av hva en living lab er, og hvordan
den kan brukes i et ZEN-pilotområde. Rapporten gir også innsikt i brukermedvirkningsprosesser som
allerede har funnet sted innenfor ZEN-pilotområder og presenterer eksempler på living labs som har
inspirert ZEN-bruk av laboratoriekonseptet.

Rapporten understreker potensialet for å bruke ZEN living lab-konseptet. En ZEN living lab er et åpent
inkluderende format som støtter brukerengasjement i ZEN-pilotprosjekter. Hensikten med å benytte
living lab-konseptet er å bygge bro mellom den sosiale og tekniske konteksten. En ZEN living lab skal
fungere som en kreativ arena for kunnskapsutveksling mellom mennesker, steder og teknologi. En arena
som ideelt sett bør gir rom for læringsprosesser. En ZEN living lab skal inneholde fire hovedelementer:

1. Representanter fra de ulike brukergruppene som er berørt av bærekraftige endringer foreslått av ZEN.
2. Et klart definert geografisk sted.
4. Et sett av iterative aktiviteter.
3. Et eksperimentelt format basert på utfordringene og behovene i pilotprosjektet.

ZEN-definisjonen av null-utslippsområder fokuserer på tekniske løsninger for reduksjon av
energiforbruk og CO2-utslipp. Det er derfor en tendens til å benytte en målbasert living lab metodikk,
som testing av tekniske løsninger, som et middel for å oppnå innovasjoner innen byggebransjen eller
energisektoren. Enhver anvendelse av ZEN living lab konseptet bør imidlertid ikke miste fokuset på det
primære målet, som er å engasjere brukergruppene som vil bli påvirket av endringene som følger med
innføringen av nullutslippsteknologi. Dette bør være i form av en åpen og inkluderende prosess.


Backe, S., Sørensen, Å. L., Pinel, D., Clauß, J. Lausselet, C., & Woods, R. (2019) Consequences of local energy supply in Norway – A case study on the ZEN pilot project Campus Evenstad
ZEN Report 17,
NTNU/SINTEF,

Popular summary in English:

(Scroll nedover for norsk sammendrag)

 

Consequences and opportunities of local energy supply at Campus Evenstad

This report evaluates Campus Evenstad towards becoming a ZEN. The goal is to present which
measures are most relevant to realize ZEN goals related to energy and develop an understanding of
potential, consequences, value, and status related to operations and investments in the energy system
at Campus Evenstad. We evaluate consequences of achieving different degrees of on-site supply of
renewable energy. Four aspects are evaluated for the energy system: (1) Value creation and regulatory
framework, (2) future investments, (3) operational control and optimization, and (4) emission
reductions.

Local energy supply is most valuable when consumed in the neighborhood

Local power supply generates economic value mainly through saved costs of reduced grid import (i.e.
delivered electricity to the neighbourhood). Saved costs are achieved due to (1) less delivered
electricity, (2) reduced grid tariff, and (3) reduced taxes and levies as the billing is based on net
metering of delivered electricity.

We have investigated future investments in the energy system at Campus Evenstad by using a linear
programming model. The results show that investments in more PV is the most cost-efficient way of
achieving annual compensation of emissions. In addition, operational control through planned
charging of battery and electric vehicles or pre-heating space and water to reduce peak loads and
minimize operational costs should be prioritized.

Campus Evenstad should aim at self-consuming local energy resources to minimize emissions. This is
because the local energy resources are based on renewable resources that replaces energy supply based
on fossil fuels other places in Europe.

This report can be used to support decisions for Statsbygg at Campus Evenstad on its way towards
ZEN. More general, consequences of energy choices in a ZEN is investigated and will be relevant for
other ZEN partners. The report incorporates several work packages in FME ZEN and connects
economic, operational, and technical aspects in the development of a Zero Emission Neighbourhood.

 

Norsk sammendrag:

Konsekvenser og muligheter knyttet til lokal energiforsyning på Campus Evenstad

Denne rapporten vurderer Campus Evenstad på veien mot ZEN. Hensikten med rapporten er å vurdere
hvilke tiltak som er relevante fremover for å realisere energimål knyttet til ZEN, og den skal gi en
forståelse for potensial, konsekvens, verdi og status knyttet til ulike tiltak relatert til drift og
investeringer i energisystemet på Campus Evenstad. Vi trekker blant annet frem konsekvenser av ulik
grad av selvforsynt fornybar energi. Fire faktorer vurderes for energisystemet: (1) Verdiskaping og
regulatorisk rammeverk, (2) fremtidige investeringer, (3) driftsoptimalisering og styringssystemer og
(4) utslippsreduksjoner.

Lokal energiproduksjon er mest verdifull om den brukes innenfor nabolaget

Lokal elektrisitetsforsyning skaper økonomisk verdi hovedsakelig gjennom sparte kostnader som følge
av mindre behov for strømimport (i.e. levert elektrisitet til nabolaget). Det skapes verdi både gjennom
(1) redusert levert strøm, (2) redusert nettleie og (3) øvrige reduserte elavgifter siden alle disse leddene
av strømregningen baseres på netto strømforbruk.

Vi har undersøkt potensielle fremtidige investeringer i energisystemet for Campus Evenstad ved hjelp
av en optimeringsmodell. Våre analyser antyder at den mest kostnadseffektive måten å oppnå årlig
kompensering av utslipp på er gjennom investeringer i flere solceller. I tillegg bør driftsoptimalisering
gjennom planlagt ladning av batteri og elbiler eller foroppvarming av rom og vann for å redusere
topplaster og minimere driftskostnader prioriteres fremover.

Campus Evenstad bør i størst mulig grad benytte lokale enheter ved energiforsyning for å minimere
utslipp. Denne påstanden kan forsvares ved at de lokale enhetene kun er driftet på fornybare
energikilder som erstatter energi produsert med fossile energikilder andre steder i Europa.
Rapporten kan brukes til å støtte videre beslutninger for Statsbygg på Campus Evenstad på veien mot
ZEN. Den gir også innsikt i konsekvenser av energivalg generelt i ZEN som er relevant for øvrige
ZEN-partnere. Arbeidet spenner på tvers av ulike fagfelt innenfor FME ZEN og binder sammen
kunnskap knyttet til økonomiske, driftsmessige og tekniske aspekter ved utviklingen av et
nullutslippsnabolag.


Nielsen, B. F., Gohari, S., Glicher, E., Baer, D., & Situmorang, W. Z. (2019) Achieving citizen participation in smart cities: Five cross-roads in the planning of the +cityxChange project in Trondheim
Conference proceedings,
Proceedings of the First International Conference on Smart Cities in Seoul from July 17 – 19, 2019. (ICSC1),

Nielsen, B. F., Baer, D., Gohari, S. & Junker, E. (2019) The Potential of Design Thinking for Tackling the “Wicked Problems” of the Smart City
Conference proceedings,
Proceedings of the 24th International Conference on Urban Planning, Regional Development and Information Society ,

E3S Web of Conferences,
volume 111,

Abstract

Energy flexibility of buildings can be used to reduce energy use and costs, peak power, CO2eq- emissions or to increase self-consumption of on-site electricity generation. Thermal mass activation proved to have a large potential for energy flexible operation. The indoor temperature is then allowed to fluctuate between a minimum and maximum value.

Many studies investigating thermal mass activation consider electric radiators. Nevertheless, these studies most often assume that radiators modulate their emitted power, while, in reality, they are typically operated using thermostat (on-off) control.

Firstly, this article aims at comparing the energy flexibility potential of thermostat and P-controls for Norwegian detached houses using detailed dynamic simulations (here IDA ICE). It is evaluated whether the thermostat converges to a P-control for a large number of identical buildings. As the buildings are getting better insulated, the impact of internal heat gains (IHG) becomes increasingly important. Therefore, the influence of different IHG profiles has been evaluated in the context of energy flexibility. Secondly, most studies about energy flexibility consider a single indoor temperature. This is questionable in residential buildings where people may want different temperature zones. This is critical in Norway where many occupants want cold bedrooms (~16°C) during winter time and open bedroom windows for this purpose.

This article answers to these questions for two different building insulation levels and two construction modes (heavy and lightweight).


Conference proceedings,
Advanced Studies in Energy Efficiency and Built Environment for Developing Countries Proceedings of IEREK Conferences: Improving Sustainability Concept in Developing Countries (ISCDC-2) ,

Abstract

The aim of this paper is to assess the gaps and needs for net-zero energy buildings (NZEBS) design and implementations in MENA Region, particularly in Egypt. The paper reviews current government efforts and regulations on energy efficiency in buildings, the academic efforts in developing NZEBs concept, as well as challenges and barriers in building design phases.

For illustration, the paper summarized study undertaken to analyze the potential challenges and opportunities for implement (NZEBs) in Egypt as an example of Mena region. Two case studies in Mena region E-JUST campus in Egypt and MASDAR City in UAE had been analyzed. The review and case studies show a lack of energy performance in Egyptian buildings code and optimization calculation methods, as well as limited numbers of academic work for NZEBs which studied the Egyptian case.

It is concluded that the current building codes and laws need to be upgraded to include the energy performance of buildings requirements, a database for buildings materials need to be developed with studies to the cost optimal for different buildings type in Egypt, one the challenges of the NZEBs in is the vernacular environment and enhancing the implementation procedures.


Frontiers in Built Environment,
volume 5,
issue 97,

Summary

Optimal ventilation strategies are fundamental to achieve net/nearly-zero energy buildings.

In this study, three hybrid ventilation control strategies are proposed to minimize the cooling need in an open-plan office building, located in the center of Glasgow (Scotland). The performance of the three proposals is assessed by IDA ICE (a whole building performance simulation tool) and compared to a traditional fully mechanical ventilation system.

The performance comparison includes different criteria (i.e., indoor temperature and predicated percentage of dissatisfied (PPD) for assessing the indoor comfort and CO2 level for assessing the indoor air quality).

The results show that the three proposed hybrid ventilation strategies are able to minimize the cooling need to zero. They can also imply a drastic reduction of AHU heating power, compared with a mechanical ventilation system without heat recovery (or with low efficiency heat recovery). In addition, they significantly save the fan energy.

The only drawback of the proposed strategies is that they might increase the space heating demand. For instance, the first and second strategies save about 75% and 50% of AHU (air handling unit) fan energy; however, the space heating increases by about 4.2 and 2.2 kWh/m2a, respectively. The third strategy features as the best proposal because it saves around 68% of fan energy with less increase (1.3 kWh/m2a) in space heating demand. Moreover, it ensures higher thermal comfort and indoor air quality levels compared to the first and second proposals.


Building and Environment,
volume 148,
pages 44-54,

Abstract

Registration, identification, and re-creation of an indoor occupant’s actions are challenges in the field of building energy performance. Commonly used measurement technologies are capable of capturing partial information regarding the occupants’ activity.

However, the combination of all existing inputs cannot grant access to a satisfying description of occupant behaviour that allows capturing profiles of occupants’ intentions and habits. It seems that there is a missing type of data that could be used as a connection platform for already existing inputs.

To connect existing data sets, there is a need to deploy a monitoring method that can identify particular individuals; however, it must do so while still providing a certain level of privacy among the monitored occupants. Fulfilment of these standards can be achieved through the use of the depth registration technique.

The entertainment industry popularized this registration technique, but this registration method has many other applications in the fields of medicine and computer vision. The most commonly used device (Microsoft Kinect) delivers high-frequency sampling (up to 30 Hz) and a moderate measurement range (up to 5 m), which allows its usage in the monitoring of medium-sized indoor spaces.

The delivered input data do not allow for the direct identification of the monitored person, and it does not require any interaction from the occupants to initialise the monitoring procedure. Due to these reasons, the potential of this measurement method was explored in terms of becoming an in situ indoor occupant behaviour monitoring technique.


Energies,
volume 12,
issue 7,

Abstract

This work introduces a generic methodology to determine the hourly average CO2eq. intensity of the electricity mix of a bidding zone.

The proposed method is based on the logic of input–output models and avails the balance between electricity generation and demand. The methodology also takes into account electricity trading between bidding zones and time-varying CO2eq. intensities of the electricity traded.

The paper shows that it is essential to take into account electricity imports and their varying CO2eq. intensities for the evaluation of the CO2eq. intensity in Scandinavian bidding zones. Generally, the average CO2eq. intensity of the Norwegian electricity mix increases during times of electricity imports since the average CO2eq. intensity is normally low because electricity is mainly generated from hydropower. Among other applications, the CO2eq. intensity can be used as a penalty signal in predictive controls of building energy systems since ENTSO-E provides 72 h forecasts of electricity generation.

Therefore, as a second contribution, the demand response potential for heating a single-family residential building based on the hourly average CO2eq. intensity of six Scandinavian bidding zones is investigated. Predictive rule-based controls are implemented into a building performance simulation tool (here IDA ICE) to study the influence that the daily fluctuations of the CO2eq. intensity signal have on the potential overall emission savings.

The results show that control strategies based on the CO2eq. intensity can achieve emission reductions, if daily fluctuations of the CO2eq. intensity are large enough to compensate for the increased electricity use due to load shifting. Furthermore, the results reveal that price-based control strategies usually lead to increased overall emissions for the Scandinavian bidding zones as the operation is shifted to nighttime, when cheap carbon-intensive electricity is imported from the continental European power grid.


Sustainable Energy Technologies and Assessments,
volume 31,
pages 228-235,

Abstract

A linear complementarity model is developed and presented for two different electricity market designs comprising an energy-only as well as a capacity market. In addition, storage units are implemented, assessing the impact of the market design on these units.

Results of a case study for northern Europe show that the availability of storage units can have a significant impact on the optimal generation mix to reduce the need for mid-merit and peaking thermal generation capacity. Given a capacity market, the derating of storage technologies creates a bias towards conventional thermal units and has a significant negative impact on the profitability and hence incentive to invest in energy storage units.

Furthermore, due to the vastly different cost characteristics and round-cycle efficiencies, it is found that batteries and pumped hydro energy storage complement each other in the power system instead of reducing each other’s business opportunities.


Master Thesis,
NTNU/Università degli Studi di Genova,

Today more then ever cities have a fundamental role not only from the design point of view but also from the social and economic one. In a century in which “urbanization” has a leading part, it is becoming more and more crucial to start toward a sustainable approach. Cities have to guarantee not only the quality of life for the inhabitants but also a low environmental impact which does not affect the needs of the future generations.

For this purpose, lot of cities in the world are reorganizing and rethinking themselves with the aim of becoming more smart and adapting to changes that could not be reversible. In an historical period in which buildings sector produces the main part of the global emissions and uses about the 40% of the energy source, the attention to the energy behaviour of the construction has assumed an essential importance. For existing buildings the energy simulation has two different advantages: to evaluate the current energy status and their improvement as a result of eventual interventions. Energy simulation has increasingly taken on a dynamic characteristic and
today is a valid tool to implement the existing built. Recently developed tools give the opportunity to estimate the energy behaviour of entire neighbourhoods and cities, giving the chance to evaluate the situation from a global and completely new point of view. The totalitarian approach and not focused on the single building, could be revolutionary and decisive for many cities that are not able to guarantee and pursue the goals regarding the sustainability.


Master Thesis,
NTNU, Trondheim,

Dette vitenskapelige arbeidet er et resultat av Sophie Schönfeldt Karlsens masteroppgave ved Institutt for bygg- og miljøteknikk på NTNU. Fire tariffstrukturer for nettleie, foreslått av NVE, er vurdert for å undersøke hvordan de påvirker økonomiske insentiver for (1) økt energieffektivisering og (2) fleksibel lastflytting i bygg. Energibruk er simulert for en norsk enebolig med en antakelse om at all energibruk er elektrisk. Parametre knyttet til byggstandard, oppvarmingsteknologi, åpning av vinduer, bygningsintegrert energiproduksjon og elbillading er vurdert i 96 ulike simuleringer, og energikostnader er beregnet for de ulike nettleiestrukturene med og uten lastflytting. Resultatene viser generelt at økt energieffektivisering gir billigere strømregning under samtlige tariffstrukturer, og at nettleiestrukturer basert på tidsvarierende effektprising gir dyrere strømregninger for kunder som ikke utfører lastflytting.