| 1. |
- Sotnikov, Artem, 1985, et al.
(författare)
-
Simulations of a solar-assisted block-heating system
- 2017
-
Ingår i: ISES Solar World Congress 2017 - IEA SHC International Conference on Solar Heating and Cooling for Buildings and Industry 2017, Proceedings. - Freiburg, Germany : International Solar Energy Society.
-
Konferensbidrag (refereegranskat)abstract
- Two types of simulation software TRNSYS and Polysun are studied to check their suitability for solar district heating system planning. A reference case, a part of the Vallda Heberg district heating system is modelled in both tools and results are compared with available measured data and with each other. Models are successfully calibrated. TRNSYS and Polysun models have deviations in main key figures compared to the reference case less than 2% and less than 8% respectively. A sensitivity analysis of key parameters shows that the two tools give similar results.
|
|
| 2. |
- Almusaed, Amjad, 1967-, et al.
(författare)
-
Assessing the Impact of Recycled Building Materials on Environmental Sustainability and Energy Efficiency : A Comprehensive Framework for Reducing Greenhouse Gas Emissions
- 2024
-
Ingår i: Buildings. - : MDPI. - 2075-5309. ; 14:6
-
Tidskriftsartikel (refereegranskat)abstract
- In this study, we critically examine the potential of recycled construction materials, focusing on how these materials can significantly reduce greenhouse gas (GHG) emissions and energy usage in the construction sector. By adopting an integrated approach that combines Life Cycle Assessment (LCA) and Material Flow Analysis (MFA) within the circular economy framework, we thoroughly examine the lifecycle environmental performance of these materials. Our findings reveal a promising future where incorporating recycled materials in construction can significantly lower GHG emissions and conserve energy. This underscores their crucial role in advancing sustainable construction practices. Moreover, our study emphasizes the need for robust regulatory frameworks and technological innovations to enhance the adoption of environmentally responsible practices. We encourage policymakers, industry stakeholders, and the academic community to collaborate and promote the adoption of a circular economy strategy in the building sector. Our research contributes to the ongoing discussion on sustainable construction, offering evidence-based insights that can inform future policies and initiatives to improve environmental stewardship in the construction industry. This study aligns with the European Union’s objectives of achieving climate-neutral cities by 2030 and the United Nations’ Sustainable Development Goals outlined for completion by 2030. Overall, this paper contributes to the ongoing dialogue on sustainable construction, providing a fact-driven basis for future policy and initiatives to enhance environmental stewardship in the industry.
|
|
| 3. |
- Andersen, Martin, 1985-, et al.
(författare)
-
Economic Analysis of Heat Distribution Concepts for a Small Solar District Heating System
- 2022
-
Ingår i: Energies. - : MDPI. - 1996-1073. ; 15:13
-
Tidskriftsartikel (refereegranskat)abstract
- One challenge in today’s district heating systems is the relatively high distribution heat loss. Lowering distribution temperatures is one way to reduce operational costs resulting from high heat losses, while changing the distribution system from steel pipes to plastic pipes and changing the heat distribution concept can reduce investment costs. The result is that the overall life cycle cost of the district heating system is reduced, leading to the improved cost competitiveness of district heating versus individual heating options. The main aim of this study was to determine the most cost-efficient distribution system for a theoretical solar district heating system, by comparing the marginal life cycle cost of two different distribution systems. A secondary aim was to determine the influence of the employed pipe type and insulation level on the marginal life cycle cost by comparing detailed economic calculations, including differences in pipe installation costs and construction costs, among others. A small solar-assisted district heating system has been modeled in TRNSYS based on a real system, and this “hybrid” model is used as a basis for a second model where a novel distribution system is employed and the heating network operating temperature is changed. Results indicate that a novel distribution concept with lower network temperatures and central domestic hot water preparation is most efficient both from an energy and cost perspective. The total life cycle costs vary less than 2% for a given distribution concept when using different pipe types and insulation classes, indicating that the investment costs are more significant than operational costs in reducing life cycle costs. The largest difference in life cycle cost is observed by changing the distribution concept, the novel concept having approximately 24% lower marginal life cycle cost than the “hybrid” system. © 2022 by the authors. Licensee MDPI, Basel, Switzerland.
|
|
| 4. |
- Andersen, Martin, 1985, et al.
(författare)
-
Heat distribution concepts for small solar district heating systems – Techno-economic study for low line heat densities
- 2022
-
Ingår i: Energy Conversion and Management: X. - : Elsevier BV. - 2590-1745. ; 15
-
Tidskriftsartikel (refereegranskat)abstract
- The high operating temperatures in today's district heating networks combined with the low energy demand of new buildings lead to high relative network heat losses. New networks featuring lower operating temperatures have reduced relative heat losses while enabling an increase in the use of solar heat. The primary aim of this study was to determine if a particular district heating system can be made more effective with respect to heat losses and useful solar energy, by considering different distribution concepts and load densities. A small solar assisted district heating system with a novel hybrid distribution system has been modelled based on a real case study. This model serves as a basis for two other models where the distribution system and heating network operating temperature is changed. A secondary aim of the study was to determine the economic implications of making these changes, by using costs estimates to calculate the contribution of essential system components to total system cost. Results indicate that a novel distribution concept with lower network temperatures and central domestic hot water preparation is most energy efficient in a sparse network with a heat density of 0.2 MWh/m∙a and a performance ratio of 66%, while a conventional district heating system performs worst and has a performance ratio of less than 58% at the same heat density. In an extremely sparse network with heat density of 0.05 MWh/m∙a, the performance ratio is 41% and 30% for these systems, respectively. A simple economic analysis indicates that the novel distribution concept is also best from an economic point of view, reducing the initial investment cost by 1/3 compared to the conventional concept, which is the most costly. However, more detailed calculations are needed to conclude on this.
|
|
| 5. |
- Lidberg, Tina, 1984-, et al.
(författare)
-
System impact of energy efficient building refurbishment within a district heated region
- 2016
-
Ingår i: Energy. - : Elsevier BV. - 0360-5442 .- 1873-6785. ; 106, s. 45-53
-
Tidskriftsartikel (refereegranskat)abstract
- The energy efficiency of the European building stock needs to be increased in order to fulfill the climate goals of the European Union. To be able to evaluate the impact of energy efficient refurbishment in matters of greenhouse gas emissions, it is necessary to apply a system perspective where not only the building but also the surrounding energy system is taken into consideration.This study examines the impact that energy efficient refurbishment of multi-family buildings has on the district heating and the electricity production. It also investigates the impact on electricity utilization and emissions of greenhouse gases.The results from the simulation of four energy efficiency building refurbishment packages were used to evaluate the impact on the district heating system. The packages were chosen to show the difference between refurbishment actions that increase the use of electricity when lowering the heat demand, and actions that lower the heat demand without increasing the electricity use. The energy system cost optimization modeling tool MODEST (Model for Optimization of Dynamic Energy Systems with Time-Dependent Components and Boundary Conditions) was used.When comparing two refurbishment packages with the same annual district heating use, this study shows that a package including changes in the building envelope decreases the greenhouse gas emissions more than a package including ventilation measures.
|
|
| 6. |
- Petrovic, Bojana, et al.
(författare)
-
Life cycle assessment of a wooden single-family house in Sweden
- 2019
-
Ingår i: Applied Energy. - : Elsevier. - 0306-2619 .- 1872-9118. ; 251, s. 1456-1465
-
Tidskriftsartikel (refereegranskat)abstract
- To understand the reasons behind the large environmental impact from buildings the whole life cycle needs to be considered. Therefore, this study evaluates the carbon dioxide emissions in all stages of a single-family house in Sweden from the production of building materials, followed by construction and user stages until the end-of-life of the building in a life cycle assessment (LCA). The methodology applied is attributional life cycle assessment (LCA) based on `One Click LCA' tool and a calculated life span of 100 years. Global warming potential (GWP) and primary energy (PE) are calculated by using specific data from the case study, furthermore the data regarding building materials are based on Environmental Product Declarations (EPDs). The results show that the selection of wood-based materials has a significantly lower impact on the carbon dioxide emissions in comparison with non-wood based materials. The total emissions for this single-family house in Sweden are 6 kg CO2e/m2/year. The production stage of building materials, including building systems and installations represent 30% of the total carbon dioxide equivalent emissions, while the maintenance and replacement part represents 37%. However, energy use during the in-use stage of the house recorded lower environmental impact (21%) due to the Swedish electricity mix that is mostly based on energy sources with low carbon dioxide emissions. The water consumption, construction and the end-of-life stages have shown minor contribution to the buildings total greenhouse gas (GHG) emissions (12%). The primary energy indicator shows the largest share in the operational phase of the house.
|
|
| 7. |
- Ranhagen, Ulf, 1947-, et al.
(författare)
-
Eco-cycle model 2.0. for Stockholm Royal Seaport City District : Feasibility study - final report
- 2014
-
Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Eco-Cycle Model 2.0. of Stockholm Royal SeaportDevelopment of the Eco-Cycle Model 2.0. is one of a total of five sub-projects in the city of Stockholm which have been granted economic support from the Swedish Delegation of Sustainable Cities in order to contribute to making the Royal Seaport in Stockholm a world-class environmental profiling urban area. The purpose of this pre-study is to investigate the options for developing an eco-cycle model that grasps more dimensions than the Hammarby Model, including overall and detailed descriptions of resource flows in different time perspectives. Important starting points for the pre-study are• Global and local challenges concerning our use of resources with specific relevance for urban development• Available models which visualise functions, resource flows and resource synergies in the eco-cycle in a qualitative way• Available accounts of material, energy and water which quantify functions and resource flowsIn order to involve stakeholders in the development process, representatives from different organisations were invited to two workshops where ideas were developed and combined. These workshops are documented in two separate reports (in Swedish).The primary objective of the eco-cycle model is to contribute to drawing attention to and explaining important connections and synergies between resource flows. Secondary objectives that can be fulfilled after supplementing the development work are: to be a tool for monitoring and follow-up of environmental objectives, to serve as a a dynamic tool for analysis of resource flows and to be more comprehensive.The proposed eco-cycle model 2.0. is not only a general map of functions and flows related to the eco-cycle which characterised the Hammarby Model, but also a line of arguments supported by illustrations on four different levels:• Level 0 Established theories and concepts for sustainable societal and urban development constituting the basis of the eco-cycle model• Level 1 Anchoring of the eco-cycle model in a more comprehensive sustainability concept• Level 2 General Map of functions and flows related to the eco-cycle model including optional systems solutions both within and outside the city district (outside the defined systems boundary). Conceptual future image for 2030 with a perspective towards 2050.• Level 3 Resource flow analysis related to accounting systems for energy, material and water eco-cycles. Conceptual future image for 2030 with a perspective towards 2050.This proposal for a conceptual eco-cycle model 2.0. should be considered as a basis for future R&D work and applications. The presented desirable situation for 2030 with a perspective towards 2050, in line with the applied back-casting methodology, may be used as a basis for defining different stages in a short-term and mid-term perspective. A number of possible development projects which should be initiated as follow-up of the pre-study are defined. One example is the need for developing pedagogical descriptions and presentations supported by visualisation and animation tools. The international perspective is also important, as there is an increasing interest in The Royal Seaport City District in a rapidly urbanising world where many cities are preparing for – or have already started –planning of city districts with high sustainability ambitions.
|
|
| 8. |
- Ranhagen, Ulf, 1947-, et al.
(författare)
-
Kretsloppsmodell 2.0. för Norra Djurgårdsstaden : Förstudie - slutrapport
- 2014
-
Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Eco-Cycle Model 2.0. of Stockholm Royal SeaportDevelopment of the Eco-Cycle Model 2.0. is one of a total of five sub-projects in the city of Stockholm which have been granted economic support from the Swedish Delegation of Sustainable Cities in order to contribute to making the Royal Seaport in Stockholm a world-class environmental profiling urban area. The purpose of this pre-study is to investigate the options for developing an eco-cycle model that grasps more dimensions than the Hammarby Model, including overall and detailed descriptions of resource flows in different time perspectives. Important starting points for the pre-study are• Global and local challenges concerning our use of resources with specific relevance for urban development• Available models which visualise functions, resource flows and resource synergies in the eco-cycle in a qualitative way• Available accounts of material, energy and water which quantify functions and resource flowsIn order to involve stakeholders in the development process, representatives from different organisations were invited to two workshops where ideas were developed and combined. These workshops are documented in two separate reports (in Swedish).The primary objective of the eco-cycle model is to contribute to drawing attention to and explaining important connections and synergies between resource flows. Secondary objectives that can be fulfilled after supplementing the development work are: to be a tool for monitoring and follow-up of environmental objectives, to serve as a a dynamic tool for analysis of resource flows and to be more comprehensive.The proposed eco-cycle model 2.0. is not only a general map of functions and flows related to the eco-cycle which characterised the Hammarby Model, but also a line of arguments supported by illustrations on four different levels:• Level 0 Established theories and concepts for sustainable societal and urban development constituting the basis of the eco-cycle model• Level 1 Anchoring of the eco-cycle model in a more comprehensive sustainability concept• Level 2 General Map of functions and flows related to the eco-cycle model including optional systems solutions both within and outside the city district (outside the defined systems boundary). Conceptual future image for 2030 with a perspective towards 2050.• Level 3 Resource flow analysis related to accounting systems for energy, material and water eco-cycles. Conceptual future image for 2030 with a perspective towards 2050.This proposal for a conceptual eco-cycle model 2.0. should be considered as a basis for future R&D work and applications. The presented desirable situation for 2030 with a perspective towards 2050, in line with the applied back-casting methodology, may be used as a basis for defining different stages in a short-term and mid-term perspective. A number of possible development projects which should be initiated as follow-up of the pre-study are defined. One example is the need for developing pedagogical descriptions and presentations supported by visualisation and animation tools. The international perspective is also important, as there is an increasing interest in The Royal Seaport City District in a rapidly urbanising world where many cities are preparing for – or have already started –planning of city districts with high sustainability ambitions.
|
|
