The ongoing transformation in European district heating systems fromthe usage of fossil-based technologies to non-fossil heat supplies issummarised by a collection of 70 possibilities linked to decarbonisation. These possibilities are exemplified by 284 implemented, planned, orproposed cases. The 70 possibilities for decarbonised district heatinginclude using heat, connecting customers, moving heat, storing heat, removing carbon dioxide, and supplying heat together with somefeatures for the entire value chain, to heat usage from heat generation orrecycling. This collection of 70 possibilities is neither complete nor doesit contain any recommendations for the possibilities or advocate forspecific possibilities.

The purpose of this project was to provide an extensive inventory ofdecarbonisation activities recently performed by district heating operators andother heat suppliers. These decarbonisation activities include the directsubstitution of heat obtained from the combustion of fossil fuels and indirectactions for obtaining more efficient district heating systems. These indirect actionsreduce costs and increase revenue, thereby improving the competitiveness ofdistrict heating. The time horizon, which is linked to the EU’s target for thereduction of greenhouse gas emissions by 55% compared to 1990 levels, is 2030. This inventory of early decarbonisation projects concerning district heatingsystems has revealed the following three key conclusions.

First, decarbonisation activities can be divided into substituting and supportingpossibilities. Substituting possibilities in heat supply include linear supply fromrenewables, heat recycling from processes that generate excess heat, and non-fossilways of meeting peak heat demands during very cold days. The linear heat supplyis based on geothermal heat, solar heat, and electricity supply. Heat recycling ispossible from various processes related to biorefineries, hydrogen supply, petrochemical plants, electricity distribution, district cooling, data centres, batteryfactories, food supply chains, and sewage waters. Heat storage can make heatdelivery more independent of heat supply and provide additional opportunities toreduce peak loads. Supporting possibilities mainly comprise activities forobtaining lower temperatures in heat distribution networks to increase profitabilitywhen using low-temperature heat sources. These activities are performed whenconnecting customers, moving heat, and using heat. Another supporting activity is the removal of biogenic carbon dioxide from the natural carbon cycle, although anappropriate international accounting system for its removal is still missing.

Second, the decarbonisation possibilities of district heating systems differ fromthose of traditional systems based on fossil fuels. The availability ofdecarbonisation possibilities for district heating depends on local conditions,whereas fossil fuels are transported from available global resources and are usedworldwide. Hereby, decarbonised district heating systems will not be as uniformas traditional systems based on fossil fuels. The local conditions lower the degrees of freedom for the implementation of substituting possibilities in existing buildingsand systems. Hence, it is important to adopt new methods for utilising the highestdegree of freedom possible in new buildings and systems.

Third, the common denominators for the 70 identified possibilities are degrees offreedom for decarbonisation, action plans for achieving lower heat distributiontemperatures, the use of heat pumps for upgrading low-temperature supplies tomeet high-temperature demands, smart digitalisation options, clear supplyresponsibilities, favourable institutional frameworks, and digital planning models. These seven common denominators are efficient tools for obtaining decarbonisedand more efficient district heating systems in the future. These redesigned and newsystems will be somewhat different than traditional systems, which have beenbased on a district heating technology that was originally elaborated for systemsbased on fossil fuels.

Den pågående omvandlingen av europeiska fjärrvärmesystem från användning av fossilbaserad teknik till icke-fossil värmeförsörjning sammanfattas med en utvald samling av 70 möjligheter kopplade till fossilfrihet. Dessa möjligheter exemplifieras med 284 genomförda, planerade eller föreslagna fall. De 70 möjligheterna för koldioxidfri fjärrvärme omfattar att använda värme, ansluta kunder, flytta värme, lagra värme, avskilja koldioxid och tillföra värme tillsammans med några aspekter för hela värdekedjan till värmeanvändning från värmeåtervinning eller värmegenerering. Uppsättningen av 70 möjligheter är varken komplett eller innehåller några rekommendationer för vilka möjligheter som bör användas. Syftet med detta projekt har varit att tillhandahålla en omfattande inventering av tidiga aktiviteter för att erhålla fossilfri fjärrvärme som nyligen utförts av fjärrvärmeföretag eller andra värmeaktörer. Dessa aktiviteter omfattar både direkt substitution av värme som tidigare erhållits från förbränning av fossila bränslen och stödjande indirekta åtgärder för att erhålla mer effektiva fjärrvärmesystem. Dessa stödjande åtgärder minskar kostnaderna eller ökar intäkterna som förbättrar fjärrvärmens konkurrenskraft. Tidshorisonten har varit 2030, kopplat till EU:s mål för minskning av växthusgasutsläppen med 55 % jämfört med 1990 års utsläpp. Denna inventering av tidiga projekt för fossilfri fjärrvärme har givit följande tre viktiga slutsatser. För det första, aktiviteter för fossilfri fjärrvärme kan delas in i ersättande och stödjande möjligheter. Ersättande möjligheter i värmeförsörjningen inkluderar linjär försörjning från förnybar energi, värmeåtervinning från processer som genererar restvärme och icke-fossila sätt att möta spetsbehov under mycket kalla dagar. Den linjära värmeförsörjningen baseras på geotermisk värme, solvärme och eltillförsel. Nya aktiviteter för värmeåtervinning är möjliga från många olika samhällsprocesser, såsom bioraffinaderier, vätgasförsörjning, petrokemiska anläggningar, eldistribution, fjärrkyla, datacenter, batterifabriker, livsmedelsförsörjning och avloppsvatten. Värmelager kan göra värmeleveransen mer oberoende av värmetillförseln, vilket också ger ytterligare möjligheter att minska spetsbelastningar. Stödjande möjligheter innehåller främst aktiviteter för att erhålla lägre temperaturer i värmedistributionsnät, vilket ökar lönsamheten vid användning av lågtempererade värmekällor. Dessa aktiviteter utförs när man använder värme, ansluter kunder och flyttar värme. En planerad stödaktivitet är också avskiljning av biogen koldioxid från det naturliga kolkretsloppet, även om ett lämpligt internationellt ersättningssystem för detta fortfarande saknas. För det andra, karaktären hos möjligheterna till fossilfritt skiljer sig från de traditionella erfarenheterna baserade på fossila bränslen. Tillgången på möjligheter till fossilfritt beror på lokala förhållanden, medan fossila bränslen transporterades från tillgängliga globala resurser, vilket gav full frihet att använda fossila bränslen var som helst i världen. Härigenom kommer fossilfria fjärrvärmesystem inte bli så 4likartade som traditionella fjärrvärmesystem var med fossila bränslen. De lokala förutsättningarna för fossilfri fjärrvärme ger något lägre frihetsgrader för implementering av ersättande möjligheter i befintliga byggnader eller system. Därför är det viktigt för framtiden att utnyttja den högre frihetsgrad som är möjlig i nya byggnader och system genom att använda nya metoder mm. För det tredje, de gemensamma nämnarna för de 70 identifierade möjligheterna är antal frihetsgrader för fossilfrihet, handlingsplaner för att erhålla lägre temperaturer i värmedistributionsnät, olika sätt att använda värmepumpar för att uppgradera låga framtemperaturer för att tillgodose högre temperaturbehov hos kunderna, möjliga smarta digitaliseringsalternativ, tydliga leveransansvar, gynnsamma institutionella ramar samt digitala planeringsverktyg. Dessa sju gemensamma nämnare är effektiva verktyg för att få mer effektiva fossilfria fjärrvärmesystem, eftersom den traditionella fjärrvärmetekniken en gång i tiden utformades för system baserade på användning av fossila bränslen. 

From now on, in 2021, new buildings in Sweden must fulfil the nZEB, near Zero Energy Buildings, concept. It implies low mean U-value (U_m) of 0.30-0.40 [W/m² K] in the buildings´ envelopes for obtaining low heat demands according to the Swedish National Board of Housing, Building and Planning. Furthermore, the new buildings must have sufficient mechanical ventilation with heat recovery. In addition, the buildings could preferably even be self-sufficient of electricity. In this context, and with a new renovation wave carried through in Europe, a new technique with low-temperature district heating is a smart, even a wise, solution. The technique is based on renewable, recovered, and stored heat.

Halmstad Energi & Miljö, HEM, and the Halmstad University and Malmö University are carrying out a transdisciplinary project in cooperation. In Part 1 of the project HEM is installing district heating for 550 new dwellings in the Ranagård district. The area will have several real estate companies/owners. HEM has planned for a sharp system solution, which use considerably lower temperature than conventional district heating. Halmstad University has developed this network configuration, which so far, never has been tested in full scale. The new technique benefits with lower heat supply costs for using renewable, recovered, and stored heat in future district heating.

The Universities are making two research analyses in addition to this extension. Part 2 of the project aims to survey acceptance, for identifying any hindrance occurring when new technology is introduced. Analyses of interviews within the construction and energy industry will show their decision making in relation to new technical solutions. Part 3 pertains to quality assurance of the new district heating technology, to ensure that this new technology is fully implemented. This paper is a first report on the implementation. © eceee and the authors 2021

Denna rapport är en summering av ett besök vid InterSolar-eventet som ägde rum 14-17 maj 2019 i München. Besöket genomfördes på uppdrag av Alexanderssoninstitutet inom deras projekt SolReg Halland med Julia Englund som projektkoordinator. Syftet med att besöka InterSolar var att göra en trendspaning i solenergibranschen. Uppdraget var att samla information för att analysera mönster. Frågorna som skulle besvaras var:

☼   Vilka trender kan vi lära av för att öka användningen av solenergi i Halland?

☼   Vad kan vi göra för att stärka solenergibranschen i Hallandsregion?

Konferensen och mässan InterSolar Europe ingår i the Smarter E Europe — the Innovation Hub for New Energy Solutions. Deras syfte är dels att uppmärksamma de innovatörer som driver omställningen av energisystemen och dels att fungera som mötesplats för solenergibranschen. Bokningsbara konferensrum fanns tillgängliga över hela konferens- och mässområdet.

Konferensen InterSolar marknadsfördes tillsammans med tre andra konferenser 14-15 maj;

• ees Europe —för lagring av elektrisk energi
• Power2drive Europe — för infrastruktur, laddning och e-mobilitet
• Smart renewable systems — för interaktiva byggnader, smarta hem och lokala mikronät.

Nästan samtidigt, 15-17 maj, genomfördes mässan InterSolar Europe tillsammans med tre andra mässor;

• ees Europe —för lagring av elektrisk energi
• Power 2 drive Europe — för infrastruktur, laddning och e-mobilitet
• EM-power — för intelligent energianvändning inom industrin och bebyggelse.

Hela konceptet genomförs såväl i Europa som i Asien, Sydamerika och Nordamerika men vid olika tidpunkter på året.

About 40 per cent of the energy produced within the European Union is consumed in and by the residential and business sector, and the same applies to Sweden. Today’s necessary focus on the climate issue with the concomitant energy issue connected to greenhouse gas emissions has resulted in stringent energy requirements even for preservation work on historically important buildings.

The scope of this thesis is topical. It is about our built heritage and how to preserve it. The issue is current EU directives on requirements for energy efficiency implemented into national legislation combined with a lack of national inventories defining what our built heritage consists of and its values. The question is whether the historic value of our built heritage will be lost in an effort to improve energy efficiency. An imbalance of preservation and energy interests within legislation is presented, showing that the concern is justified. A model for balancing those interests to avoid one-sided valuations is therefore proposed.

A transdisciplinary arena was created comprising multiple professions from academia as well as from practice because the scope is too broad to be covered by one discipline. A case study with multiple units of analysis was performed. The case study has been applied to restored buildings and the management of the preservation work carried out. The combined energy, architectural and preservation issues and the management have been investigated for use as part of the basis for the proposed model. Nine workshops have been carried out forming a transdisciplinary arena and together with the case study and studies of the disciplines and their methods they form the foundation from which the working model has emerged as an iterative design process. This thesis is a theoretical work based in large part on many professionals´ practical experiences.

The overall objective was to create a working model for practical application regarding the balancing of energy and preservation demands, and furthermore to design methods for management and collaboration for engaged professions, particularly architects, the conservation professions and engineers who work with the properties and values at risk of being neglected. The premise is that most buildings must be used if they are to be preserved, and improved energy efficiency for better comfort and indoor climate and reduced energy costs is a prerequisite for their use.

The aim was to design a model and methods that can provide a working environment built on transparency and mutual respect for the different professions and their skills, an environment in which participants feel free to question motives and causes of proposed actions for an enhanced understanding of their impact on specific aspects of a project and on the project as a whole. To facilitate the process, a framework for the balancing has been created consisting of documents and templates organised in a model with seven steps, intertwined with some investigated possible methods and concepts that are useful for the performance of the working model. The designed model and supporting methods can be used in various kinds of early stages in building processes, and is hence relevant for use even in countries other than Sweden.

The project EEPOCH concerns our built heritage and the complex set of problems that exist between energy efficiency and preservation perspectives. New legislation demanding efficient energy use is predicated on the documented potential of energy efficiency on both national and international levels. Due to the severe environmental impact of energy consumption and diminishing fossil energy sources, energy efficiency is considered a key action. Concerns have been raised, however, as to whether the historic value of our built heritage will be lost, to the advantage of energy efficiency actions. There is a need for models directed towards the application of an integrated balancing of energy and preservation demands. The aim of this study is to find a way to design such theoretical models. Three cases with objects restored in the 1990s have been studied by analysing and comparing their energy performance and their different historic and architectural values. In doing so, a case study methodology of pattern-matching has been used for literal and theoretical replications. Transdisciplinary and interdisciplinary approaches have been used in the research. The multiple case study and issues concerning both energy performance and conservation have been discussed in workshops. Academics and practitioners participated, some of them providing facts on the cases and all of them contributing with their knowledge, expertise, experience and advice to root the study in approved practice and theory. The results show that some energy efficiency actions may be carried out without diminishing their different historic values, but these have low impact on the energy consumption. The results also show that energy efficiency actions that are too small may result in a poor indoor climate. This study also highlights unforeseen issues. The impact of a new legal and regulatory framework on alterations in existing buildings had to become an embedded unit of analysis, showing that concerns for lost heritage values are justified. The traditional way of assessing the different historic values proved to be insufficient from an architect’s point of view and a complementary way is presented. Moreover, new ways of assessing historic value are currently being tested by the Swedish National Heritage Board and the National Property Board. The case where energy efficiency actions and preserved historic value can be balanced is dependent on this assessment. A thorough evaluation is recommended.