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

ZEN Report 4,
NTNU/SINTEF,

Abstract

This report is a part of Work Package 3 Responsive and Energy Efficient buildings. The goal for WP 3 is to create cost effective, responsive, resource and energy efficient buildings by developing low carbon technologies and construction systems based on lifecycle design strategies.

As conventional HVAC systems can only make most users satisfied with their thermal environment, there has recently been a lot of research into personal climatization systems. The aim of this literature study was to investigate whether personal heating and cooling solutions could contribute to make all users satisfied with their thermal environment. Potential energy savings are considered a bonus, but was also included in the evaluation of the literature on the subject.

Almost all of the articles reviewed in this report found that the personal climatization devices significantly improved thermal sensation and thermal comfort for the users. For both heating and cooling it was found that combining personal comfort devices resulted in higher comfort improvement and higher energy saving potential. The devices also made it possible to achieve thermal comfort outside the traditional heating and cooling setpoints, thus making it possible to extend the thermal dead-band of buildings, which could lead to substantial energy savings. There are however still some aspects of personal climatization systems where there is suggested further research, and these personal climatization systems are still not commercially available.

Øystein Rønneseth

Walnum, H.T. & Fredriksen, E. (2018) Thermal energy systems in ZEN
ZEN Report 3,
NTNU/SINTEF,

This report reviews the state-of-the-art on thermal energy systems for neighbourhoods. Its main focus is on technologies related to 4th generation district heating (4GDH), biomass combined heat and power (CHP) systems, ground source heat pumps (GSHP) and seasonal heat storage.

Harald Taxt Walnum, Eyvind Fredriksen

Næss, J.S., Sandberg, N.H., Nord, N., Vestrum, M.I., Lausselet, C., Woszczek, A., Rønneseth, Ø. & Brattebø, H. (2018) Neighbourhood building stock model for long-term dynamic analyses of energy demand and GHG emissions
ZEN Report 2,
NTNU/SINTEF,

How should sustainable neighbourhoods be designed to reduce greenhouse gas emissions towards zero? What kind of information do decision makers need to make solid future plans on the neighbourhood level? A dynamic building stock model has been developed for energy- and GHG-emission scenario analyses of neighbourhoods. The model is generic and flexible and can be used to model any neighbourhood where building stock data is available.

Jan Sandstad Næss, Nina Holck Sandberg, Natasa Nord, Magnus Inderberg Vestrum, Carine Lausselet, Aleksandra Woszczek, Øystein Rønneseth, Helge Brattebø

ZEN Report 1,
NTNU/SINTEF,

This report presents a plan for the European power market studies to be carried out within the ZEN Research Centre.

Local energy solutions such as the utilization of local renewable energy resources, and increased energy efficiency, are important for being able to reduce European greenhouse gas emissions to amounts that are in line e.g. with a 2 degree global warming. In the long run, emission levels are affected by many factors including energy system operations, investment decisions, policy instruments, social acceptance for environmental policy, amongst others. Thus, it is not trivial to calculate the full impacts of e.g. 1 TWh extra renewable energy produced locally. Still, it is possible to elaborate on and reveal important mechanisms, which will increase our understanding of those. This report present a plan for European power market studies to be carried out within the FME ZEN. The overall intention with the planned studies is not to provide more accurate numerical calculations than in previous studies, but rather to show how numerical results are affected by which economic mechanisms that are included in such studies. Thus, the studies shall be a basis for creating increased mutual understanding of arguments within FME ZEN.

Ove Wolfgang

ZEB Report 41,
NTNU/SINTEF,

This report presents a set of guidelines to assist building designers in a methodological approach to the analysis of energy systems in the early design phase of zero emission buildings. The guidelines are meant to accompany the use of a ZEB supporting tool, guiding through the necessary steps to evaluate the performance and adapt the dimensioning of different systems to the case at hand.

Igor Sartori, Sjur V. Løtveit, Kristian S. Skeie

Sartori, I., Skeie, K.S., Sørnes, K. & Andresen, I. (2018) Zero Village Bergen: Energy system analysis
ZEB Report 40,
NTNU/SINTEF,

Based on discussions with the ZEB partners, three possible solutions have been investigated for the energy system of Zero Village Bergen:

  1. District Heating (DH)
  2. Biomass fired Combined Heat and Power (Bio CHP)
  3. Ground Source Heat Pump (GSHP)
Igor Sartori, Kristian S. Skeie, Kari Sørnes, Inger Andresen

Nord, N., Tereshchenko, T., Qvistgaard, L.H., & Tryggestad, I.S. (2018) Influence of occupant behavior and operation on performance of a residential Zero Emission Building in Norway
Energy and Buildings,
volume 159,
pages 75-88,

Abstract

It has been proven that occupant behavior may significantly change building energy performance. The effect of the occupant behavior is becoming even bigger when it comes to highly energy efficient buildings. Specifically Zero Emission Buildings (ZEB) may become an issue for the electric grid, because they are supposed to be actively connected to the electricity grid for electricity import and export. Therefore, the aim of this study was to evaluate the change in the energy performance of a ZEB located in Norway.

Occupant behavior was modelled by using the following methods standard schedules, well-defined profiles based on thorough statistical analysis, and stochastic methods To analyze the grid stress, 31 scenarios for different occupant behaviors were analyzed. The overall estimation of investigated parameters showed that the change in occupant behavior resulted in grid stress variance from −5% to +13% compared to the reference case based on the standard values.

The results showed that the occupant behavior might change the annual energy balance reliability by 20%. However, the results showed that the influence of the occupant behavior related to the window opening and domestic hot tap water would not significantly change the ZEB energy performance. Window opening would even decrease the cooling load. A very important conclusion of this study is that consideration of occupant behavior through challenging the standard values are highly necessary for reliable energy analysis of the ZEB solutions.


Energy and Buildings,
volume 146,
pages 220-232,

Abstract

The housing sector is important for future energy savings and greenhouse gas emission mitigation. A dynamic, stock-driven and segmented dwelling stock model is applied for dwelling stock energy analyses. Renovation activity is estimated as the need for renovation during the ageing process of the stock, in contrast to exogenously defined and often unrealistic renovation rates applied in other models.

The case study of Norway 2016–2050 shows that despite stock growth, the total theoretical estimated delivered energy is expected to decrease from 2016 to 2050 by 23% (baseline) and 52% (most optimistic scenario). A large share of the energy-efficiency potential of the stock is already realized through standard renovation. The potential for further reductions through more advanced and/or more frequent renovation, compared to current practice, is surprisingly limited. However, extensive use of heat pumps and photovoltaics will give large additional future energy savings. Finally, user behaviour is highly important. A strong future rebound effect is expected as the dwelling stock becomes more energy efficient. The estimated total ‘real’ energy demand is expected to decrease by only 1% (baseline) and 36% (most optimistic scenario). Hence, reaching significant future energy and emission reductions in the Norwegian dwelling stock system will be challenging.


Seljom, P., Lindberg, K.B., Tomasgard, A., Doorman, G. & Sartori, I. (2017) The impact of Zero Energy Buildings on the Scandinavian energy system
Energy,
volume 118,
pages 284-296,

Abstract

This paper investigates how an extensive implementation of net Zero Energy Buildings (ZEBs) affects cost-optimal investments in the Scandinavian energy system towards 2050. Analyses are done by a stochastic TIMES model with an explicit representation of the short-term uncertainty related to electricity supply and heat demand in buildings. We define a nearly ZEB to be a highly efficient building with on-site PV production. To evaluate the flexibility requirement of the surrounding energy system, we consider no use of energy storage within the ZEBs.

The results show that ZEBs reduce the investments in non-flexible hydropower, wind power and Combined Heat and Power, and increase the use of direct electric heating and electric boilers. With building integrated PV production of 53 TWh in 2050, ZEBs increase the Scandinavian electricity generation by 16 TWh and increase the net electricity export by 19 TWh. Although the increased production reduces the electricity prices, the low heat demand in ZEBs gives a drop in the electricity consumption by 4 TWh in 2050. Finally, the results demonstrate that the Scandinavian energy system is capable of integrating a large amount of ZEBs with intermittent PV production due to the flexible hydropower in Norway and Sweden.


Sørnes, K., Fredriksen, E., Tunheim, K. & Sartori, I. (2017) Analysis of the impact resolution has on load matching in the Norwegian context
Energy Procedia,
volume 132,
pages 610-615,

Abstract

Generation of energy at building level has an increasing interest in Norway, as in rest of Europe. Load matching is the correlation between the buildings generation and load, which in most cases aims at optimization of the amount of self-consumption. When analysing generation in relation to load, it is of interest to study the choice of resolution and what impact this has on load match indicators. This study analyses the importance of choosing the right resolution, starting with hourly measurements, and going down towards one-minute resolution.

Monitoring resolution has a significant impact on both the type of monitoring equipment and the data storage capacity needed. If the impact of lower resolution is small, less complex monitoring systems can be installed in projects that are not sensible to the uncertainty caused by the lack of minute-based data.
Norwegian case studies with solar power production gives data to the analysis, studying a nursing home in Oslo called Økern Sykehjem. The nursing home has been a pilot building in the European Fp7 research project ZenN, Nearly Zero Energy Neighbourhood (2012-2017), which led to the installation of 130 kW solar power panels while going through a large renovation process. Generation and load have been monitored with high-resolution since 2015 and this gives useful insight into the effect of high-resolution data monitoring compared to hourly-resolution monitoring.

Resulting graphs shows that by collecting data on a daily basis will give a wrong impression on self-consumption and self-generation by about 20% compared to hourly based data. The difference between minute based and hourly based resolution is relatively small (6%).


Zhang, L., Gustavsen, A., Jelle, B.P., Yang, L., Gao, T. & Wang, Y. (2017) Thermal conductivity of cement stabilized earth blocks
Construction and Building Materials,
volume 151,
pages 504-511,

Abstract

The present study examines the effect of bulk density and cement content on the thermal conductivity of cement stabilized earth blocks (CSEB). The experimental results show that the thermal conductivity increases as a function of bulk density; changes in cement content result in a small variation in thermal conductivity of CSEB at a given bulk density. No obvious linear relationship between the thermal conductivity and cement content of CSEB has been observed. However, a significant increase of compressive strength of CSEB caused by the addition of cement has been observed; moreover, the compressive strength of CSEB increases with increasing cement content. CSEB show potential in earth buildings due to their improved compressive strength and reduced thermal conductivity.


Usman, D. & Ascher, B. (2018) Mot nullutslipps nabolag – hvorfor?
Vvsforum.no,
04.01.2018,

Mer enn 70% av verdens energirelaterte klimagassutslipp er tilknyttet byer. Byggesektoren bruker halvparten av total elektrisitetsbruk i fastlands Norge. Det er derfor rimelig tydelig at utfordringer tilknyttet klima ligger i planleggingen og bruken av byene – men også løsningene.

Usman Dar og Barbara Ascher

Østlendingen (Newspaper),
09.12.2017,

VI MÅ jo bare takke og bukke for at MDG-eren Martin Løken har opphøyd seg selv til elverumpolitikkens moroklump. Med utspillet om å skrinlegge Ydalir har han tatt belastningen med å bli latterliggjort og utskjelt. Å sette dagsorden med hovedoppslag og en tosiders avisartikkel for noe som får uttrykket «bak mål» til å framstå som tomt og innholdsløst, er en prestasjon i seg selv. Men det uredde og frimodige Martin mest av alt har klart, er å få øynene opp på flere for hva som egentlig foregår i Ydalir.

Halvard Berget

Op-ed by Odd-Erling Lange (2017) Skal vi skrinlegge Elverum?
Østlendingen (Newspaper),
04.12.2017,

Kun innpakningen er grønn, sier MDGs Martin Løken om Ydalir til Østlendingen. Vi er glade for Løkens engasjement, bare synd det baserer seg på misforståelser som kan skade Elverums attraktivitetsarbeid for fortsatt økt tilflytning.

Odd-Erling Lange

Press release (2017) ZEN utvikler nullutslippsområder
Press release,
6 November 2017,
3,

Ti måneder etter oppstarten er FME ZEN allerede godt i gang med å planlegge og utvikle områder uten klimagassutslipp. Forskningssenter for nullutslippsområder i smarte byer (FME ZEN) skal utvikle løsninger for framtidens bygninger og byområder, løsninger som bidrar til at nullutslippssamfunnet kan realiseres.

Kathrine Nitter, Arild Gustavsen

Elmagasinet,
2 March 2017,

Nå skal NTNU og Sintef bygge ZEB Flexible Lab. Bygget, som blir et kontor- og undervisningsbygg, får en sentral plass i det nye forskningssenteret Zero Emission Neighbourhoods in Smart Cities (ZEN) og senter for forskningsdrevet innovasjon, Klima 2050.

Elmagasinet

News story (2017) Ny kunnskap fra ZEN
VVS Aktuelt,
23 February 2017,

NTNU og byggebransjen har valgt ut sju områder for å demonstrere hvordan nabolag kan bidra til nullutslipp i det nye, store ZEN-prosjektet. Allerede i 2019 kan de første nullnabolagene stå klare.


News story (interview with Annemie Wyckmans) (2017) An Interview with Annemie Wyckmans
Zero Emission Architecture,
79 (3),
12-17.,

An Interview with Annemie Wyckmans on Sino-Norwegian Architecture Forum: Zero Emission Architecture, Special Issue «Architecture of Tomorrow». Community Design 2017

Annemie Wyckmans

News story (interview with Anne Grete Hestnes and Arild Gustavsen) (2017) Nullutslippshus kan bli fremtidens byggeforskrift
Byggeindustrien,
19 January 2017,

Alt om tre-fire år kan nye byggeforskrifter her i landet være basert på de erfaringer og kunnskap som man har fått fra det store ZEB-prosjektet (Zero emission buildings) ved NTNU/Sintef som har pågått i flere år.

Arne Sellæg, Anne Grete Hestnes, Arild Gustavsen

News story (2016) En positiv fusjonshistorie
Universitetsavisa,
14 June 2016,

Institutt for produktdesign (IPD) i Trondheim og medie- og designfag ved Seksjon for medieteknologi (MTL) i Gjøvik har funnet hverandre og vil danne et nytt Institutt for design under Fakultet for arkitektur og design. Begge fagmiljøer er enige om at det ligger spennende muligheter i fusjonen og at et nytt institutt har stort potensial. Felles deltakelse i det nye FME ZEN (Zero Emission Neighbourhoods) vil være en ekstra pådriver.

Terje Stafseng, Casper Boks

News story (interview with Arild Gustavsen and Terje Jacobsen) (2016) Oslo, Bergen, Trondheim, Bodø, Steinkjer, Elverum og Evenstad blir innovasjonsarena og utprøvingsområder
ITBAktuelt,
27 May 2016,

The Research Centre on Zero Emission Neighbourhoods in Smart Cities/Forskningssenter for nullutslippsområder i smarte byer (FME ZEN) skal utvikle løsninger for framtidens bygninger og byområder – løsninger som bidrar til at nullutslippssamfunnet kan realiseres.

Arild Gustavsen, Terje Jacobsen

News story (2016) Trøndersk storeslem
Dagens Næringsliv,
27 May 2016,

Under Forskningsrådets energikonferanse torsdag tildelte rådet penger til åtte nye forskningssentre for miljøvennlig energi (FME).

Frode Buanes

 


Asplan Viak (website),
27 May 2016,

Asplan Viak blir partner i nytt forskningssenter for miljøvennlig energi. Her skal vi være med å skape fremtidens løsninger gjennom utvikling av bærekraftige byområder – med null utslipp av klimagasser. Løsninger som bidrar til at nullutslippssamfunnet kan realiseres.

Liv Bjørhovde Rindal

News story (2015) Ny bydel som forskermat
Østlendingen,
24 October 2015,

Elverum kommune og Elverum Tomteselskap har gått inn som partnere i forskningssenteret Zen i Trondheim, ledet av NTNU og SINTEF. Bydelen Ydalir legges i potten som forskningsobjekt.

Randi Undseth, Anna-Thekla Tonjer