| 1. |
- Abaravicius, Juozas, et al.
(författare)
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Analysing Load Demand in Households
- 2006
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Ingår i: Energy Efficiency in Domestic Appliances and Lighting (EEDAL) conference proceeding. - 9789279027529
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Konferensbidrag (refereegranskat)abstract
- The importance of load demand variation, when analysing energy and environmental impact of residential energy use, is increasing. Load demand in residential houses is a significant contributor to peak load problems experienced by utilities. The knowledge about demand variation in households is limited as well as the use of methodologies to analyse the demand is. Many utilities have recently installed interval (hourly) metering at their residential customers. The availability of this data is a big step forward, however, our experience show that the utilities use this data only to a limited extent, mostly for billing purposes only. This study aims to discuss the ways and benefits of using this valuable end-use data. There are several established load analysis tools, such as load curve, typical load curve, load duration curve, load factor, superposition factor, etc., which utilities could apply and develop. Among other benefits, the hourly load data analysis can provide the detailed characteristics of load demand in households, define the consumption patterns and can help to identify the main contributors to the utility peaks. This information is essential when developing new energy services, appropriate pricing, load management strategies and demand response programs. This paper analyses strengths and weaknesses of different analysis tools, the knowledge they could give, how applicable they are and what value they could have for the utility and the customer. The study is exemplified with ten “real world” cases in Southern Sweden, where the households with electric space heating and hot water systems are analysed.
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| 2. |
- Abaravicius, Juozas, et al.
(författare)
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More or Less about Data - Analyzing Load Demand in Residential Houses
- 2006
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Ingår i: [Host publication title missing].
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Konferensbidrag (refereegranskat)abstract
- Load demand in residential houses is a significant contributor to peak load problems experienced by utilities. The knowledge about demand variation in households is fairly limited as well as the use of various tools to analyze the demand. Many utilities have recently installed interval (hourly) metering at their residential customers. The availability of hourly data is a significant progress, however, the utilities use this data only to a limited extent, mostly for billing purposes only. This study aims to discuss the possibilities and the benefits of using this valuable data. There are several established load analysis tools, such as load curve, typical load curve, load duration curve, load factor, superposition factor, etc., which utilities could apply and develop to provide feedback to small electricity users. Among other benefits, the hourly load data analysis can provide the detailed characteristics of load demand, define the consumption patterns and can help to identify which households contribute most to the utility peaks. This information is essential when developing new energy services, appropriate pricing, load management strategies and demand response programs. Through the analysis of strengths and weaknesses of different load analysis tools, this paper defines the knowledge they could give, how applicable they are and what value they could have both for the utility and the residential customer. The study is exemplified with ten cases of households with electric space heating in Southern Sweden.
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| 3. |
- Abaravicius, Juozas, et al.
(författare)
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Turn Me On, Turn Me Off! Techno-Economic, Environmental and Social Aspects of Direct Load Management in Residential Houses
- 2005
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Ingår i: META Energy Savings: What Works and Who Delivers? eceee Summer Study Proceedings. V. 1-3. - 9163140020
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Konferensbidrag (refereegranskat)abstract
- Load management is a techno-economic measure for harmonizing the relations between supply and demand sides, optimising power generation and transmission and increasing security of supply. It can also benefit the environment by preventing use of generators with higher emissions. This study was performed in collaboration with one electric utility in Southern Sweden, which aims solving peak load problems either with load management or by constructing diesel peak power plant. The objective of the study was to experimentally test and analyse the conditions and potential of direct load management from customer and utility viewpoint. Techno-economic and environmental aspects as well as customer experiences were investigated. Ten electric-heated houses were equipped with extra meters, enabling hourly load measurements for heating, hot water and total electricity use. Household heating and hot water systems were controlled by the utility using an existing remote reading system. The residents were informed about the experiment but not about the time and duration of the controls. The experiment was followed up by interviews. According to the interviews, the residents noticed some of the control periods of heating. Body activity level as well as compensation of sun radiation and heat producing appliances influenced the experiences. After the experiments the households were positive about load control, but they expressed requirements for the implementation of such measures.
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| 4. |
- Averfalk, Helge, 1988-
(författare)
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Enhanced District Heating Technology : Maintaining Future System Feasibility
- 2017
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- When heat demand and high temperature heat supply gradually decreases in the future, then it will effect district heating systems ability to compete on the heat market. A good way to mitigate less district heating feasibility is to operate systems with lower temperature levels and the most conceivable way to achieve lower temperature levels is to decrease return temperatures.Thus, this thesis emphasise temperature errors embedded in district heating systems. Only a selection of temperature errors are analysed in this thesis. First, the temperature error that occurs due to recirculation in distribution networks at low heat demands. Second, the temperature error that occurs due to hot water circulation in multi-family buildings. Third, the temperature error that occurs due to less than possible heat transfer in heat exchangers, i.e. too short thermal lengths.In order to address these temperature errors three technology changes have been proposed (i) three-pipe distribution network to separate the recirculation return flow from the delivery return flow, (ii) apartment substations to eliminate hot water circulation utilisation, and (iii) improved heat exchangers for lower return temperatures at a constant scenario. Analysis of proposed changes has resulted in annual average return temperatures between 17-21 °C.Furthermore, rapid introduction of intermittent renewable electricity supply in the energy system has prompted an increased necessity of power system balancing capacities. Large-scale conversion of power-to-heat in electric boilers and heat pumps is a feasible alternative to achieve such balancing capacities. Analysis of the unique Swedish experience with utilisation of large heat pumps installations connected to district heating systems show that since the 1980s 1527 MW of heat power has been installed, about 80 % of the capacity was still in use by 2013. Thus, a cumulative value of over three decades of operation and maintenance exists within Swedish district heating systems.The two papers presented in this thesis are related to future district heating systems through the five abilities of fourth generation district heating (4GDH), which are documented in the definition paper of 4GDH.
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| 5. |
- Brange, Lisa, et al.
(författare)
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Bottlenecks in district heating networks and how to eliminate them - A simulation and cost study
- 2017
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Ingår i: Energy. - : Elsevier BV. - 0360-5442. ; 137, s. 607-616
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Tidskriftsartikel (refereegranskat)abstract
- To optimise district heating (DH) systems and simplify the transition towards the fourth generation of district heating, it is important to remove any bottlenecks existing in the DH network. DH bottlenecks are in this study defined as pipes with too high flow relative to the pipe diameter, resulting in difficulties to maintain sufficient differential pressure in the area beyond the pipe. The aim of this study is to investigate how well possible measures to solve bottleneck problems work in different DH network configurations and how much they cost. This was achieved by a simulation study and a cost analysis. The results showed that DH systems with a lower flow rate demanded more extensive measures than other systems and that different problems might arise in different types of networks. The economic results showed that a lot of varying parameters, such as the internal rate of return, the fuel and electricity prices and the annual utilisation time of the measure could have a large impact on the outcome. An increase of the supply temperature could however easily become very expensive. Before any bottleneck measures are implemented in a DH system, calculations and analysis based on the local situations should thus be performed.
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| 6. |
- Brange, Lisa, et al.
(författare)
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Bottlenecks in district heating systems and how to address them
- 2017
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Ingår i: Energy Procedia. - : Elsevier BV. - 1876-6102. ; 116, s. 249-259
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Tidskriftsartikel (refereegranskat)abstract
- Problems with bottlenecks in district heating networks occur when the pipes have too small dimensions to sufficiently meet customer needs. This may result in insufficient differential pressure in DH areas attached to these pipes. Bottlenecks are especially common in expanding DH networks, as previously sufficient pipe diameters may become too small when more DH consumers are connected to the DH network. Historically, bottlenecks have often been addressed by increasing the supply temperature or by exchanging the pipe to a larger dimension. Other techniques are however available to solve bottleneck problems. Such techniques are for example installation of local heat supply on the other side of the bottleneck (LHS), demand side management (DSM), or installation of thermal energy storage (TES). The aim of this study was to identify different techniques for addressing bottlenecks and to see what solutions were used by the DH companies in Sweden. A literature study of the different techniques available was performed and a survey study with the DH distribution companies in Sweden that are members of the Swedish DH association was carried out. The survey was sent out to in total 131 companies, of which 89 answered. The results showed that the most used techniques in Sweden are a higher supply temperature and installation of a new pipe to increase the pipe area, whereas for example DSM and TES were more rarely used techniques. This work is an introduction to the different techniques used to address bottleneck problems and shows the bottleneck situation in Swedish DH networks. More research and tests are however necessary in order to more thoroughly evaluate which techniques that should be used in different situations.
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| 7. |
- Brange, Lisa, et al.
(författare)
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Decision-making process for addressing bottleneck problems in district heating networks
- 2019
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Ingår i: International Journal of Sustainable Energy Planning and Management. - 2246-2929. ; 20:2019, s. 37-50
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Tidskriftsartikel (refereegranskat)abstract
- Lower system temperatures in district heating (DH) grids are important factors for system efficiency. Lower system temperatures lead, for example, to lower heat losses and higher production unit efficiency. One obstacle to lower supply temperatures are so-called bottlenecks in DH networks. Bottlenecks are areas in DH networks of very low differential pressure, which makes it difficult to supply them with sufficient heat. There are many potential solutions to bottlenecks. However, the current decision-making process generally does not include every potential bottleneck solution and also often does not include every important factor that affects the outcome. The aim of this study is to propose a structured and general modus operandi, in order to identify the best bottleneck solution for a specific situation. In this study we conducted analyses of previous bottleneck studies, workshops and interviews. The results show a decision-making process developed to be a tool when choosing a bottleneck solution. Coupled to the decision-making process, a summary of the advantages and disadvantages of different factors and bottleneck solutions is presented, as well as a description of a real case in which the decision-making process is used.
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| 8. |
- Brange, Lisa, et al.
(författare)
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Risks and opportunities for bottleneck measures in Swedish district heating networks
- 2018
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Ingår i: 16th International Symposium on District Heating and Cooling, DHC2018, 9–12 September 2018, Hamburg, Germany. - : Elsevier BV. - 1876-6102. ; 149, s. 380-389
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Konferensbidrag (refereegranskat)abstract
- Heat supply bottlenecks are common in district heating (DH) networks and makes the DH network work in a non-optimal way, why it is beneficial to address them. The purpose of this paper is thus to investigate risks, opportunities, added values and issues coupled to various bottleneck measures. This is made by in depth interviews with DH companies and through DH network simulations. The results showed numerous risks and opportunities coupled to each bottleneck measure investigated, and are meant to highlight more effective measures, to help increase the competitiveness of and improve the environmental performance of DH.
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| 9. |
- Calvén, Alexandra, et al.
(författare)
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From vision to reality – integrating energy goals in the development of a new urban district in Sweden
- 2024
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Ingår i: eceee 2024 Summer Study Proceedings. - 9789198827026 - 9789198827033
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Konferensbidrag (refereegranskat)abstract
- Urban areas play an important role in attaining the sustainability and energy goals set by municipalities. Despite the often ambitious sustainability visions and goals for new urban areas, there is limited understanding of how these aspirations are integrated into the planning and development process. This paper aims to provide insights into how energy-related visions and goals, in a new district in Sweden, are formulated and further translated into instruments employed by the municipality. Brunnshög, a new sustainability-profiled district in Lund envisioned to become a leading example of sustainable urban development, is used as a case study. The district’s long-term energy goal is to generate more energy than what is used, emphasizing a strong focus on energy efficiency and local renewable energy generation. Key to Brunnshög’s energy strategy is the implementation of the world’s largest low-temperature district heating network supplied with excess heat from two high-tech research facilities. The planning process for Brunnshög began in 2006 and the district is expected to be completed in 2055, accommodating an estimated 40,000 residents and workers.Adopting a municipal planning perspective, this paper combines analysis of planning documents with interviews conducted with developers and the municipality’s project manager for Brunnshög. The results provide an overview of how the energy-related visions and goals for Brunnshög have been included in the planning documents for the district and describe the utilization of three instruments used by the municipality to achieve these visions and goals: (1) collaboration contract with the local energy company, (2) land allocation competitions, and (3) sustainability agreements with the developers.The formulation of visions and goals for Brunnshög, divided into long-term visionary goals and more immediate operational goals, allows for adjustments of specific aspects based on changing circumstances while still maintaining a commitment to broader visions and goals. The translation of energy goals into commitments is an evolving process, with the level of ambition influenced by factors such as the demand for housing and office space, competition among developers, and prevailing sustainability trends. This paper concludes that the integration of sustainability criteria into land allocation competitions is a powerful instrument for driving ambitious building projects. However, in contexts where the municipality lacks ownership of the land or faces subdued market conditions, there is a need for additional tools to be developed. Furthermore, sustainability agreements with developers serve as an important tool to track the sustainability commitments made in land allocation competitions. However, implementing a more systematic review and evaluation of these agreements, including long-term assessments, is necessary to learn from the experiences and hold the actors accountable. The findings of this study contribute to a better understanding of how energy goals can be sustained throughout lengthy urban development processes. Insights gained from development processes such as Brunnshög are essential for implementing the necessary changes to decrease the climate impact of new urban development projects and to mainstream the practices of sustainable urban development.
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| 10. |
- Gåverud, Henrik, et al.
(författare)
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Kundernas uppfattning om förändrade prismodeller
- 2016
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Tidigare svenska studier om prissättning och prismodeller i fjärrvärmeverksamhet har bidragit med viktiga aspekter ur ett produktionsperspektiv på hur man kan tänka vid utformning av prismodeller för fjärrvärme. Dessa studier har framförallt tryckt på att fjärrvärmens prismodeller bör återspegla fjärrvärmebolagets kostnader för produktion och distribution av fjärrvärme i kundledet då detta minskar fjärrvärmebolagens ekonomiska risker vid förändringar i fjärrvärmeunderlaget eller i kundernas uttagsmönster. Denna studie har haft som syfte att bredda bilden och synen på vad man bör beakta vid framtagande av prismodeller för fjärrvärme genom att lägga till ett tydligt kundperspektiv. Syftet har varit att analysera kunders syn på fjärrvärmebolagens prismodeller och de förändringar som skett avseende dessa modeller. Ett kvalitativt angreppssätt har valts i denna studie. Anledningen till detta är frågeställningens karaktär. Det är inte alla fjärrvärmekunder som är insatta i hur prismodellen som de debiteras är utformad och fungerar. Vi såg därför ett behov av att kunna diskutera och ställa följdfrågor till kunderna. För att nå en fördjupad dynamik i diskussionerna valdes fokusgruppintervjuer som metod. Totalt sex fokusgruppintervjuer har genomförts – en för större och en för mindre kunder för vart och ett av de tre företag som har ingått i studien. Dessa företag är Sala-Heby Energi, Södertörns Fjärrvärme och Öresundskraft. Södertörns Fjärrvärme och Öresundskraft har under senare år infört prismodeller som ska generera priser som bättre återspeglar företagets kostnader. Sala-Heby Energi har valt att gå en annan väg, företaget har helt slopat de fasta avgifterna och effektavgifterna. Företaget har endast ett rörligt energipris som kunderna betalar för. Utifrån de resultat som har framkommit från studiens sex fokusgruppintervjuer står det klart att det finns en divergens mellan vilka egenskaper som kunderna vill att en prismodell för fjärrvärme ska ha och tidigare studiers rekommendationer som trycker på kostnadsreflektering och riskminimering för företagen. De främsta egenskaperna som kunderna lyfter fram för en bra prismodell ur ett kundperspektiv är följande: • Energieffektivisering måste löna sig, kundernas kostnader ska vara påverkbara av kundernas beteende • Prismodellen ska vara enkel att förstå och enkel att kommunicera – kunden vill förstå vad den betalar för • Kunderna vill kunna förutse kommande kostnader för att kunna lägga budget Den egenskap som kunderna ser som allra viktigast i fjärrvärmebolagens sätt att ta betalt för fjärrvärme är att energieffektiviseringsåtgärder måste löna sig och att prismodellen ska vara påverkbar av kundernas beteende. Vidare vill kunderna ha prismodeller som går att förstå och kommunicera till andra. Ju mer komponenter och kategorier som finns i prismodellerna, desto svårare är det för kunderna att förstå hur olika åtgärder som kunderna gör slår igenom och desto svårare är det att lägga budget. Större kunder såsom kommuner och fastighetsbolag betonar behovet av förutsägbarhet. Utifrån fokusgruppintervjuerna föreföll effektavgiften vara den del i fjärrvärmebolagens prismodeller som utgjorde det största störnings- och orosmomentet för kunderna. Komponenten är problematisk utifrån flera av de faktorer som kunderna ser som viktiga för en bra prismodell. Vidare har olika fjärrvärmebolag olika definitioner och sätt att ta betalt för effekt. Detta är något de större fastighetsbolagen som ingick i studien hade synpunkter på. För de som äger fastigheter i olika områden är det svårt att hålla reda på alla olika definitioner och det försvårar beräkningar och budgetering. En branschgemensam norm för hur man definierar och tar betalat för kapacitet efterfrågades av dessa kunder. Flödespremier, som har till syfte att ge kunderna incitament att effektivisera sina kundcentraler, är också svåra att förstå för kunderna. Ska man som fjärrvärmebolag använda sig av flödespremier får man förbereda sig på att det krävs en hel del arbete med att ta fram information kring flödesavgiften och ett enkelt sätt att förklara varför fjärrvärmebolaget vill ha tillbaka en låg returtemperatur. Det kan även vara svårt för kunder att förstå bakgrunden och syftet till införande av säsongsdifferentierade priser. Det kan vara en pedagogisk utmaning för fjärrvärmeleverantören att motivera att värmen ska vara dyrare på vintern än på sommaren – utifrån ett kundperspektiv blir värmen då dyrare när den behövs som mest medan den blir billigare när man i princip inte behöver någon värme. Fokusgruppintervjuerna indikerar dock att det är lättare att förklara och motivera säsongsdifferentierade priser än ovan nämnda effekt- och flödeskomponenter. Är prismodellen begriplig i övrigt verkar kunderna acceptera de prismässiga säsongsvariationerna. Vi kan alltså konstatera att det föreligger ett glapp mellan de strategier som förordas i branschen som trycker på att fjärrvärmebolagen genom prismodellen ska minimera sina ekonomiska risker vid förändrat fjärrvärmeunderlag eller uttagsmönster och kundernas behov och önskemål när det gäller fjärrvärmens prismodeller. Denna studie har haft som syfte att bredda bilden och synen på vad man bör beakta vid framtagande av prismodeller för fjärrvärme genom att lägga till ett tydligt kundperspektiv. Syftet har dock inte varit att ge något färdigt recept på hur prismodellerna ska se ut då det finns många perspektiv att ta hänsyn till. Den viktigaste rekommendationen som kommer ifrån denna studie blir därför att fjärrvärmebolagen har en viktig läxa att göra när det gäller att väga de olika perspektiven mot varandra. Detta måste göras med vetskapen om att olika mål och perspektiv kanske inte är kongruenta mot varandra. Genom att ta ut höga fasta kostnader i kundledet säkrar fjärrvärmeföretagen sina investeringar vilket kan vara en strategi för möta hoten om minskade värmelaster i framtiden. Samtidigt riskerar detta att skapa ett missnöje hos kunderna. En övergripande och central slutsats i studien rör alltså även det kommunikativa och kundrelationen i stort. Kunderna verkar vilja känna att fjärrvärmebolaget är närvarande, behjälpligt och förstår kundernas situation. Det tycks vara lika viktigt att man som fjärrvärmeleverantör kommunicerar och hur man gör det som vad man kommunicerar. Även den relation som fjärrvärmebolaget har med kunderna vid införandet av en ny prismodell påverkar hur kunderna tar emot prismodellsförändringen. Vid en stark relation är förtroendekapitalet stort för fjärrvärmebolaget vilket ökar kundernas beredvillighet att se förändringen i positiv dager eller åtminstone något som inte nödvändigtvis måste vara av ondo för kunderna. Vid en svag eller dålig kundrelation ökar kundernas misstänksamhet för prismodellen och fjärrvärmebolagens underliggande skäl att vilja ändra sin prismodell.
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