| 1. |
- Larsson, Simon, et al.
(författare)
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Reviewing electricity production cost assessments
- 2013
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Ingår i: Renewable & sustainable energy reviews. - : Elsevier BV. - 1364-0321 .- 1879-0690. ; 30, s. 170-183
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Tidskriftsartikel (refereegranskat)abstract
- A thorough review of twelve recent studies of production costs from different power generating technologies was conducted and a wide range in cost estimates was found. The reviewed studies show differences in their methodologies and assumptions, making the stated cost figures not directly comparable and unsuitable to be generalized to represent the costs for entire technologies. Moreover, current levelized costs of electricity methodologies focus only on the producer's costs, while additional costs viewed from a consumer perspective and on external costs with impact on society should be included if these results are to be used for planning. Although this type of electricity production cost assessments can be useful, the habit of generalizing electricity production cost figures for entire technologies is problematic. Cost escalations tend to occur rapidly with time, the impact of economies of scale is significant, costs are in many cases site-specific, and country-specific circumstances affect production costs. Assumptions on the cost-influencing factors such as discount rates, fuel prices and heat credits fluctuate considerably and have a significant impact on production cost results. Electricity production costs assessments similar to the studies reviewed in this work disregard many important cost factors, making them inadequate for decision and policy making, and should only be used to provide rough ballpark estimates with respect to a given system boundary. Caution when using electricity production cost estimates are recommended, and further studies investigating cost under different circumstances, both for producers and society as a whole are called for. Also, policy makers should be aware of the potentially widely different results coming from electricity production cost estimates under different assumptions.
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| 2. |
- Moberg, Christina, et al.
(författare)
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De unga gör helt rätt när de stämmer staten
- 2022
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Ingår i: Aftonbladet. - 1103-9000.
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Tidskriftsartikel (populärvet., debatt m.m.)abstract
- 1 620 forskare och lärare i forskarvärlden: Vi ställer oss bakom Auroras klimatkrav
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| 3. |
- Davidsson Kurland, Simon, 1986
(författare)
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Energy use for GWh-scale lithium-ion battery production
- 2020
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Ingår i: Environmental Research Communications. - : IOP Publishing. - 2515-7620. ; 2:1
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Forskningsöversikt (refereegranskat)abstract
- Estimates of energy use for lithium-ion (Li-ion) battery cell manufacturing show substantial variation, contributing to disagreements regarding the environmental benefits of large-scale deployment of electric mobility and other battery applications. Here, energy usage is estimated for two large-scale battery cell factories using publicly available data. It is concluded that these facilities use around 50–65 kWh (180–230 MJ) of electricity per kWh of battery capacity, not including other steps of the supply chain, such as mining and processing of materials. These estimates are lower than previous studies using data on pilot-scale or under-utilized facilities but are similar to recent estimates based on fully utilized, large-scale factories. The environmental impact of battery manufacturing varies with the amounts and form of energy used; especially as renewable sources replace electricity from fossil fuels. As additional large-scale battery factories are taken into use, more data should become available, and the reliance on outdated, unrepresentative, and often incomparable, estimates of energy usage in the emerging Li-ion battery industry should be avoided.
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| 4. |
- Davidsson Kurland, Simon, 1986, et al.
(författare)
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The energetic implications of introducing lithium-ion batteries into distributed photovoltaic systems
- 2019
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Ingår i: Sustainable Energy and Fuels. - : Royal Society of Chemistry (RSC). - 2398-4902. ; 3:5, s. 1182-1190
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Tidskriftsartikel (refereegranskat)abstract
- Batteries for stationary applications can prove to be crucial for enabling high penetration of solar energy, but production and use of batteries comes with an energetic cost. This study quantifies how adding a lithium-ion (Liion) battery affects the energetic performance of a typical residential photovoltaic (PV) system for a wide range of climatic conditions. If all generated power is either self-consumed or made available via the existing distribution grid, the PV system has an energy return on investment (EROI) of between 14 (Alaska) and 27 (Arizona). While adding a 12 kWh Li-ion battery increases self-consumption considerably, this has the negative effect of decreasing the EROI by more than 20%. In a situation where all excess power generation is curtailed, the EROI can be as low as 7 (Alaska and Washington), although it can also be as high as 15 (Florida). Introducing a battery increases EROI but is still considerably lower than in cases where use excess power generation is added to the grid. Doubling the battery size increases the average self-consumption marginally, but further decreases EROI of the system because the extra energy invested to build the additonal battery is used inefficienctly. The results show that installing PV systems in locations with good solar resources and a grid that can accept excess prodution is desirable for maximizing net energy return from distributed PV. Batteries have a benefit when excess electricity generation can not be fed into the grid. Oversizing batteries has the effect of significantly reducing the EROI of the PV system.
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| 5. |
- Davidsson Kurland, Simon, et al.
(författare)
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The energetic implications of introducing lithium-ion batteries into distributed photovoltaic systems
- 2019
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Ingår i: Sustainable Energy & Fuels. - 2398-4902. ; 3:5, s. 1182-1190
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Tidskriftsartikel (refereegranskat)abstract
- Batteries for stationary applications can prove to be crucial for enabling high penetration of solar energy, but production and use of batteries comes with an energetic cost. This study quantifies how adding a lithium-ion (Li-ion) battery affects the energetic performance of a typical residential photovoltaic (PV) system under a wide range of climatic conditions. If all generated power is either self-consumed or made available via an existing distribution grid, the PV system will have an energy return on investment (EROI) of between 14 (Alaska) and 27 (Arizona). While adding a 12 kW h Li-ion battery increases self-consumption considerably, this has a negative effect of decreasing the EROI by more than 20%. In a situation where all excess power generation is curtailed, the EROI can be as low as 7 (Alaska and Washington), although it can also be as high as 15 (Florida). Introducing a battery increases the EROI but it is still considerably lower than in cases where excess power generation is added to the grid. Doubling the battery size increases the average self-consumption marginally, but further decreases the EROI of the system because the extra energy invested to build the additional battery is used inefficiently. The results show that installing PV systems in locations with good solar resources and a grid that can accept excess production is desirable for maximizing the net energy return from distributed PV systems. Batteries have a benefit when excess electricity generation cannot be fed into the grid. Oversizing batteries has the effect of significantly reducing the EROI of the PV system.
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| 6. |
- Davidsson, Simon, et al.
(författare)
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A review of life cycle assessments on wind energy systems
- 2012
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Ingår i: The International Journal of Life Cycle Assessment. - : Springer Science and Business Media LLC. - 0948-3349 .- 1614-7502. ; 17:6, s. 729-742
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Forskningsöversikt (refereegranskat)abstract
- PurposeSeveral life cycle assessments (LCA) of wind energy published in recent years are reviewed to identify methodological differences and underlying assumptions.MethodsA full comparative analysis of 12 studies were undertaken (10 peer-reviewed papers, 1 conference paper, 1 industry report) regarding six fundamental factors (methods used, energy use accounting, quantification of energy production, energy performance and primary energy, natural resources, and recycling). Each factor is discussed in detail to highlight strengths and shortcomings of various approaches.ResultsSeveral potential issues are found concerning the way LCA methods are used for assessing energy performance and environmental impact of wind energy, as well as dealing with natural resource use and depletion. The potential to evaluate natural resource use and depletion impacts from wind energy appears to be poorly exploited or elaborated on in the reviewed studies. Estimations of energy performance and environmental impacts are critically analyzed and found to differ significantly.Conclusions and recommendationsA continued discussion and development of LCA methodology for wind energy and other energy resources are encouraged. Efforts should be made to standardize methods and calculations. Inconsistent use of terminology and concepts among the analyzed studies are found and should be remedied. Different methods are generally used and the results are presented in diverse ways, making it hard to compare studies with each other, but also with other renewable energy sources.
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| 7. |
- Davidsson, Simon, 1986-
(författare)
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Global energy transitions : Renewable energy technology and non-renewable resources
- 2015
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The global energy system is dominated by the use of fossil fuels. This system suffers from several problems, such as different environmental issues, while the long-term energy security is sometimes questioned. As an alternative to this situation, a transition to a global energy system based on renewable energy technologies, to a large extent solar and wind energy, is commonly proposed. Constructing the technology needed for such a transition requires resources and how fast this could happen is somewhat disputed. This thesis explores methods to assess the potential constraints for realizing such a transition by looking at potential technology growth rates and outlooks of production of the required natural resources.The thesis is based on three papers presenting case studies that look at growth rates of wind energy as well as future production outlooks of lithium and phosphate rock. Using different types of growth patterns reaching proposed installed capacities of wind power, annual commissioning requirements are investigated, taking account for the limited life expectancy oftechnology. Potential outlooks of mineral production are explored using resource constrained curve-fitting models on global lithium production. A more disaggregated model looking at individual countries are used on phosphate rock production to investigate new perspectives on production outlooks.It is concluded that the growth rates of individual energy technologies affect the resource requirements and prospective constraints on energy transitions. Resource constrained modelling of resource production can provide spans of potential outlooks for future production of resources required for anenergy transition. A higher disaggregation of the modelling can provide new perspectives of potential constraints on future production. These aspects should be further investigated when proposing alternative future energy systems.
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| 8. |
- Davidsson, Simon, et al.
(författare)
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Growth curves and sustained commissioning modelling of renewable energy : Investigating resource constraints for wind energy
- 2014
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Ingår i: Energy Policy. - : Elsevier BV. - 0301-4215 .- 1873-6777. ; 73, s. 767-776
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Tidskriftsartikel (refereegranskat)abstract
- Abstract Several recent studies have proposed fast transitions to energy systems based on renewable energy technology. Many of them dismiss potential physical constraints and issues with natural resource supply, and do not consider the growth rates of the individual technologies needed or how the energy systems are to be sustained over longer time frames. A case study is presented modelling potential growth rates of the wind energy required to reach installed capacities proposed in other studies, taking into account the expected service life of wind turbines. A sustained commissioning model is proposed as a theoretical foundation for analysing reasonable growth patterns for technologies that can be sustained in the future. The annual installation and related resource requirements to reach proposed wind capacity are quantified and it is concluded that these factors should be considered when assessing the feasibility, and even the sustainability, of fast energy transitions. Even a sustained commissioning scenario would require significant resource flows, for the transition as well as for sustaining the system, indefinitely. Recent studies that claim there are no potential natural resource barriers or other physical constraints to fast transitions to renewable energy appear inadequate in ruling out these concerns.
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| 9. |
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| 10. |
- Davidsson, Simon
(författare)
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Left-right Orientation, Homeownership and Class Position in Sweden
- 2018
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Ingår i: Scandinavian Political Studies. - : Wiley. - 0080-6757. ; 41:4, s. 309-331
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Tidskriftsartikel (refereegranskat)abstract
- Sweden is a country where left-right orientation structures the political landscape, homeownership is increasingly important, and the importance of class for political preferences and behavior is changing or even weakening. This article explores the significance of homeownership for left-right orientation in Sweden, and extends the relationship to include class position. By combining detailed cross-sectional survey data with data on regional house price variations it suggests that homes function as an economic asset that affects individual political preferences. Furthermore, the relationship between homeownership and left-right orientation is expected to be driven by particular class groups, whose labor market position imply a more leftist orientation, while their status as homeowners imply a more rightist one. The expectation is borne out, which indicates that the asset function of homes help accounting for changing class patterns of left-right orientation in Sweden.
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