1. |
- Farsaei, Anahita, et al.
(författare)
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Electricity Market Impacts of Low-carbon Energy Transition in the Nordic-Baltic Region
- 2022
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Ingår i: Journal of Sustainable Development of Energy, Water and Environment Systems. - : SDEWES Centre. - 1848-9257. ; 10:3
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Tidskriftsartikel (refereegranskat)abstract
- The Baltic countries Estonia, Latvia and Lithuania are well connected to the Nordic countries Finland and Sweden on the electricity market, yet in a different position facing the transition to a low-carbon electricity system. While especially Sweden is a large electricity producer and net exporter, the Baltic countries suffer from a lack of capacity, which makes them highly dependent on trade. In addition, the present electricity mix of Estonia is very carbon intensive compared to the Nordic countries. There is a debate regarding nuclear power in Sweden. This paper explores four possible solutions for a Nordic-Baltic electricity system: with and without nuclear power in Sweden and with the current transmission network, as well as with a considerably expanded network. The impact on electricity mix, electricity prices, carbon dioxide intensity and import dependence in the Baltic countries from the EU transition to electricity systems with very low carbon dioxide emissions is investigated. The electricity and district heat market model Enerallt is used to quantify electricity prices, electricity trade and system costs. The results show that the development of the transmission network affects electricity prices and especially electricity trade in the Baltic countries. With transmission expansion, the demand weighted average prices in the Baltic countries increase from 62 (sic)/MWh to 65 (sic)/MWh and 70 (sic)/MWh with and without nuclear power in Sweden, respectively. If transmission is expanded, phasing out nuclear power in Sweden can increase the revenue from electricity export by over 100% for the Baltic countries. However, significant new investment in wind power is required.
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2. |
- Kan, Xiaoming, 1988
(författare)
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Exploring the future low-carbon electricity system: impacts of nuclear power and demand patterns
- 2021
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- To achieve the climate goals set by the Paris Agreement, the global electricity system is expected to transition towards a low-carbon electricity system. The future low-carbon electricity system is uncertain regarding both generation and demand. First, the cost of variable renewable energy (VRE) technologies, such as wind and solar, has been decreasing over the past decade and the share of VRE in the electricity system is increasing. This trend is likely to continue for the foreseeable future. However, there is no consensus as to whether the goal of deep decarbonization of the electricity system can be accomplished without large cost escalation if nuclear power and fossil fuel plus carbon capture and storage (CCS) are excluded. Second, the future electricity demand is highly uncertain due to economic growth, e-mobility, electric heating, electric cooling, etc. These factors affect not only the volume of annual electricity demand, but also the inter-temporal electricity demand pattern. The change in demand pattern may affect a low-carbon electricity system with a high penetration level of wind and solar, as such a system is less capable of load following, as compared with the conventional electricity system based on dispatchable thermal power plants. This thesis investigates the impacts of nuclear power and demand patterns on the future low-carbon electricity system, and addresses the following research questions: What is the cost of a future low-carbon electricity system without nuclear power for Sweden?; and How will the electricity demand pattern affect the electricity system cost and the electricity supply mix? A greenfield techno-economic cost optimization model with a high temporal resolution for the electricity system is developed and used to answer these questions. The results of this work reveal that including nuclear power in the electricity system reduces the nodal net average system cost by 4% for Sweden. This implies that the economic rationale for Sweden as a country to invest in nuclear power is limited if there is a transition towards a low-carbon electricity system in Europe. In addition, we find that varied electricity demand patterns (seasonal and diurnal variations) affect only slightly the electricity system cost, except for the case of summer peak, where the system cost may increase by up to 8%. The demand pattern may have a stronger impact on the electricity supply mix, especially solar and storage capacities, than on the electricity system cost. This thesis contributes to a better understanding of the potential future low-carbon electricity system. The results are beneficial in identifying the implications for the planning of the future electricity system, policy support for low-carbon technologies, and demand profile treatment for modeling studies.
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3. |
- Kan, Xiaoming, 1988
(författare)
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From Sweden to the world: Analysis of future low-carbon electricity systems
- 2023
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The increasing urgency of addressing climate change, along with the sustained cost declines in wind and solar power, has led to a rapid expansion in their deployment to decarbonize the electricity sector. In cost-optimal scenarios for future low-carbon electricity systems, wind and solar often serve as the cornerstone of electricity supply. Although many studies have investigated a future low-carbon electricity system based on wind and solar, there are still several important aspects that are not well understood for such a future system, e.g., uncertainty in future electricity demand patterns, potential for trade in renewable energy, the spatial scope for resource sharing and the role of nuclear power. This thesis investigates these aspects and their potential impacts on developing a low-carbon electricity system. This thesis reveals that varied electricity demand patterns affect only slightly the electricity system cost for Europe, except for the case of summer peak, where the system cost may increase by up to 8%. The change in demand pattern is generally more consequential to the electricity supply mix than the system cost. Notably, the increased electric cooling demand may change the demand pattern such that the hourly electricity demand is better correlated with the output of solar PV. Through analyzing seven different regions under various CO2 emission targets, this thesis shows that solar PV is the most cost-optimal generation technology for meeting the cooling demand. In addition, to have a more realistic assessment of renewable energy potential, this thesis introduces a new metric “Renewable levelized cost of electricity available for export”, which incorporates heterogeneous discount rates, electricity demand, and land-use requirements. By applying this metric to most of the countries in the world, this thesis shows that countries with significant potential for renewable energy export include the US, China, and Saudi Arabia. Furthermore, this thesis shows that the benefit of an intercontinental super grid, as suggested by the One Sun One World One Grid initiative, is rather limited. Allowing for long-distance intercontinental electricity trade reduces the electricity system cost by 0-5% compared to the case where the continents are isolated from each other. This thesis also shows that integrating different continents always reduces the integration of solar PV, which indicates that an intercontinental super grid is not a cost-effective variation management strategy for solar power. Finally, this thesis shows that including nuclear power in the electricity system reduces the nodal net average system cost by 4% for Sweden. This implies that the economic rationale for Sweden as a country to invest in nuclear power is limited if there is a transition towards a low-carbon electricity system in Europe. This thesis provides practical information about demand profile treatment for modeling practice, introduces a useful metric for renewable energy trade potential assessment, and generates valuable insights about deploying solar PV to power cooling, and investment in super grid and nuclear power.
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4. |
- Kan, Xiaoming, 1988, et al.
(författare)
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Into a cooler future with electricity generated from solar photovoltaic
- 2022
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Ingår i: iScience. - : Elsevier BV. - 2589-0042. ; 25:5
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Tidskriftsartikel (refereegranskat)abstract
- The fast-growing global cooling demand due to income growth in tropical countries necessitates substantial investments in new generation capacity. Despite the synergy between the temporal behavior of cooling demand and solar PV production, it is not clear whether the increased cooling demand will make solar PV more cost-effective or less so. We use a capacity expansion model to investigate the cost-effectiveness of investing in solar PV to meet the electricity demand linked to cooling for seven different regions under various CO2 emission targets. Solar PV plays a dominant role in meeting the additional electricity demand for cooling, and the share of solar PV in the additional generation capacity ranges from 64% to 135%. Additionally, powering electric cooling with mainly solar PV is cheaper than powering the rest of the demand. These results suggest that solar PV may comprise the backbone of electricity supply for cooling in the future electricity system.
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5. |
- Kan, Xiaoming, 1988, et al.
(författare)
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The cost of a future low-carbon electricity system without nuclear power – the case of Sweden
- 2020
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Ingår i: Energy. - : Elsevier BV. - 0360-5442 .- 1873-6785. ; 195
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Tidskriftsartikel (refereegranskat)abstract
- To achieve the goal of deep decarbonization of the electricity system, more and more variable renewable energy (VRE) is being adopted. However, there is no consensus among researchers on whether the goal can be accomplished without large cost escalation if nuclear power is excluded in the future electricity system. In Sweden, where nuclear power generated 41% of the annual electricity supply in 2014, the official goal is 100% renewable electricity production by 2040. Therefore, we investigate the cost of a future low-carbon electricity system without nuclear power for Sweden. We model the European electricity system with a focus on Sweden and run a techno-economic cost optimization model for capacity investment and dispatch of generation, transmission, storage and demand-response, under a CO2 emission constraint of 10 g/kWh. Our results show that there are no, or only minor, cost benefits to reinvest in nuclear power plants in Sweden once the old ones are decommissioned. This holds for a large range of assumptions on technology costs and possibilities for investment in additional transmission capacity. We contrast our results with the recent study that claims severe cost penalties for not allowing nuclear power in Sweden and discuss the implications of methodology choice.
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6. |
- Kan, Xiaoming, 1988, et al.
(författare)
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The impacts of the electricity demand pattern on electricity system cost and the electricity supply mix: A comprehensive modeling analysis for Europe
- 2021
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Ingår i: Energy. - : Elsevier BV. - 0360-5442 .- 1873-6785. ; 235
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Tidskriftsartikel (refereegranskat)abstract
- Energy system models for long-term planning are widely used to explore the future electricity system. Typically, to represent the future electricity demand in these models, historical demand profiles are used directly or scaled up linearly. Although the volume change for the electricity demand is considered, the potential change of the demand pattern is ignored. Meanwhile, the future electricity demand pattern is highly uncertain due to various factors, including climate change, e-mobility, electric heating, and electric cooling. We use a techno-economic cost optimization model to investigate a stylized case and assess the effects on system cost and electricity supply mix of assuming different demand patterns for the models. Our results show that differences in diurnal demand patterns affect the system cost by less than 3%. Similarly, demand profiles with a flat seasonal variation or a winter peak result in only minor changes in system cost, as compared to the present demand profile. Demand profiles with a summer peak may display a system cost increase of up to 8%, whereas the electricity supply mix may differ by a factor of two. A more detailed case study is conducted for Europe and the results are consistent with the findings from the stylized case.
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7. |
- Sheng, Weili, et al.
(författare)
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Design matters: New insights on optimizing energy consumption for residential buildings
- 2021
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Ingår i: Energy and Buildings. - : Elsevier BV. - 0378-7788. ; 242
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Tidskriftsartikel (refereegranskat)abstract
- In this paper, we construct a unique database for 1228 residential buildings in Hong Kong to investigate how the spatial features of these residential buildings affect the electricity consumption in the communal area. We choose Hong Kong for this analysis as the city owns a large number of standard-type residential buildings managed by the public institution, which could be affected strongly by environmental policies. Both the machine learning method, based on the Least Absolute Shrinkage and Selection Operator (LASSO), and econometric regressions are adopted to analyse the data. We first utilize the machine learning LASSO technique to identify the most relevant factors for the subsequent econometric analysis. Our results show that the electricity demand for relatively low consumption building types, such as Twin Tower, is 6% lower than that of the high consumption building types. Newly constructed buildings usually belong to the medium consumption types, with the estimated monthly electricity consumption per apartment in communal areas to be around 50.2 kWh on average in 2020. These findings shed light on the nexus between spatial features and energy use for complex buildings, potentially contributing to the better crafting of energy-saving policy and the improvement of residential building programmes.
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