| 1. |
- Cowie, A. L., et al.
(author)
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Applying a science-based systems perspective to dispel misconceptions about climate effects of forest bioenergy
- 2021
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In: Global Change Biology Bioenergy. - : John Wiley and Sons Inc. - 1757-1693 .- 1757-1707. ; 13:8, s. 1210-1231
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Journal article (peer-reviewed)abstract
- The scientific literature contains contrasting findings about the climate effects of forest bioenergy, partly due to the wide diversity of bioenergy systems and associated contexts, but also due to differences in assessment methods. The climate effects of bioenergy must be accurately assessed to inform policy-making, but the complexity of bioenergy systems and associated land, industry and energy systems raises challenges for assessment. We examine misconceptions about climate effects of forest bioenergy and discuss important considerations in assessing these effects and devising measures to incentivize sustainable bioenergy as a component of climate policy. The temporal and spatial system boundary and the reference (counterfactual) scenarios are key methodology choices that strongly influence results. Focussing on carbon balances of individual forest stands and comparing emissions at the point of combustion neglect system-level interactions that influence the climate effects of forest bioenergy. We highlight the need for a systems approach, in assessing options and developing policy for forest bioenergy that: (1) considers the whole life cycle of bioenergy systems, including effects of the associated forest management and harvesting on landscape carbon balances; (2) identifies how forest bioenergy can best be deployed to support energy system transformation required to achieve climate goals; and (3) incentivizes those forest bioenergy systems that augment the mitigation value of the forest sector as a whole. Emphasis on short-term emissions reduction targets can lead to decisions that make medium- to long-term climate goals more difficult to achieve. The most important climate change mitigation measure is the transformation of energy, industry and transport systems so that fossil carbon remains underground. Narrow perspectives obscure the significant role that bioenergy can play by displacing fossil fuels now, and supporting energy system transition. Greater transparency and consistency is needed in greenhouse gas reporting and accounting related to bioenergy.
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| 2. |
- Linderholm, Carl Johan, 1976, et al.
(author)
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1st International Conference on Negative CO2 Emissions - Summary and Highlights
- 2018
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In: GHGT 2018 - 14th International Conference on Greenhouse Gas Control Technologies. - : International Energy Agency Greenhouse Gas, IEAGHG.
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Conference paper (peer-reviewed)abstract
- Negative CO2 emissions technologies include a number of technologies and biospheric storage options, the objective of which is the removal of atmospheric CO2 and thus the limitation of future global warming. An international conference on negative emissions technologies was conceived to meet the need for a broader understanding of the possibilities and challenges facing these technologies. The International Conference on Negative CO2 Emissions was held in May 22-24, 2018, at Chalmers University of Technology, Gothenburg, Sweden. The conference was organized by Chalmers with support from the Global Carbon Project, the City of Gothenburg, Nordic Energy Research, ECOERA, the Center for Carbon Removal, Göteborg Energi, Stockholm Exergi, and the International Energy Agency, i.e. IEAGHG, IEAIETS and IEA Bioenergy. The purpose of the conference was to bring together a wide range of scientific and technological disciplines and stakeholders, in order to engage in various aspects of research relating to negative CO2 emissions. This included various negative emission technologies, socio-economic and climate modelling, and climate policies and incentives. The conference was a major scientific event and the first in a conference series. The next conference will be held in the spring of 2020. This paper reports highlights and important messages from the conference.
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| 3. |
- Pihl, Erik, 1981, et al.
(author)
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Thermo-Economic Optimization of Hybridization Options for Solar Retrofitting of Combined-Cycle Power Plants
- 2014
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In: Journal of solar energy engineering. - : ASME Press. - 0199-6231 .- 1528-8986. ; 136:2, s. 021001-
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Journal article (peer-reviewed)abstract
- A thermo-economic optimization model of an integrated solar combined-cycle (ISCC) has been developed to evaluate the performance of an existing combined-cycle gas turbine (CCGT) plant when retrofitted with solar trough collectors. The model employs evolutionary algorithms to assess the optimal performance and cost of the power plant. To define the trade-offs required for maximizing gains and minimizing costs (and to identify ‘optimal’ hybridization schemes), two conflicting objectives were considered, namely, minimum required investment and maximum net present value (NPV). Optimiza- tion was performed for various feed-in tariff (FIT) regimes, with tariff levels that were either fixed or that varied with electricity pool prices. It was found that for the givencombined-cycle power plant design, only small annual solar shares (?1.2% annual share, 4% of installed capacity) could be achieved by retrofitting. The integrated solar combined-cycle design has optimal thermal storage capacities that are several times smaller than those of the corresponding solar-only design. Even with strong incentives to shift the load to periods in which the prices are higher, investment in storage capacity was not promoted. Nevertheless, the levelized costs of the additional solar-generated electricity are as low as 10 ce/kWh, compared to the 17–19 ce/kWh achieved for a reference, nonhybridized, “solar-only” concentrating solar power plant optimized with the same tools and cost dataset. The main reasons for the lower cost of the integrated solar combined-cycle power plant are improved solar-to-electric efficiency and the lower level of required investment in the steam cycle. The retrofitting of combined-cycle gas turbine plants to integrated solar combined-cycle plants with parabolic troughs represents a viable option to achieve relatively low-cost capacity expansion and strong knowledge building regarding concentrating solar power.
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| 4. |
- Pihl, Erik, 1981, et al.
(author)
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THERMOECONOMIC OPTIMISATION OF SOLAR HYBRIDISATION OPTIONS FOR EXISTING COMBINED-CYCLE POWER PLANTS
- 2011
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In: IEA SolarPACES 2011.
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Conference paper (peer-reviewed)abstract
- A model of an integrated solar combined cycle power plant has been developed in order to examine the performance of a combined-cycle plant when retrofitted with solar collectors. The model was then used for multi-objective thermo-economic optimisation of both the power plant performance and cost, using a population-based algorithm. In order to examine the trade-offs that must be made and identify ‘optimal’ hybridisation schemes and operating conditions, two conflicting objectives will be considered, namely minimum investment costs and maximum annual solar share. It was found that only small annual solar shares (~1%) can be achieved during retrofitting, but that the cost of the additional solar-generated electricity is comparably low, with equivalent levelised electricity costs of ≤10 c€/kWh.
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| 5. |
- Rootzén, Johan, 1978, et al.
(author)
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Supply-chain collective action towards zero CO2 emissions in infrastructure construction : Mapping barriers and opportunities
- 2020
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In: IOP Conference Series. - : IOP Publishing Ltd. ; , s. 042064-
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Conference paper (peer-reviewed)abstract
- Successful decarbonisation of the supply chains for buildings and infrastructure, including the production of basic materials, will involve the pursuit - in parallel - of measures to ensure circularity of material flows, measures to improve material efficiency, and to radically reduce CO2 emissions from basic materials production. Emphasis in this work has been on how “intangible” factors such as implicit or explicit constraints within organisations, inadequate communication between actors in the supply chain, overly conservative norms or lack of information, hinder the realisation of the current carbon mitigation potential. Although this work draw primarily from experiences in Sweden and other developed economies we believe the focus on innovations in the policy arena and efforts to develop new ways of co-operating, coordinating and sharing information between actors (SDG17) and on practices and processes that could enable more sustainable resource use in infrastructure construction may be of relevance also elsewhere. Not the least, since there are still many regions of the world where much of the infrastructure to provide basic services remains to be built (SDG6-7, SDG9, SDG11) a challenge that must be handled in parallel with efforts to reduce/erase the climate impact from infrastructure construction (in line with the Paris Agreement and SDG13).
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| 6. |
- Söder, Lennart, 1956-, et al.
(author)
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Är kärnkraften nödvändig för en fossilfri, svensk, elproduktion?
- 2020
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Reports (pop. science, debate, etc.)abstract
- Efter flera år av stöd har sol- och vind-el blivit ekonomiskt konkurrenskraftiga och börjat konkurrera ut stora termiska anläggningar för elproduktion. Det stängs nu kol- och kärnkraftverk i flera länder i världen och förespråkare för dessa teknologier hävdar, på olika sätt, att marknaden styr fel och att dessa kraftverk ”behövs” av olika skäl.I denna rapport har vi undersökt om det finns någon grund för ett sådant ”behov” av kärnkraftverk i Sverige som motiverar att det sker nyinvesteringar trots att konkurrensen på marknaden håller på att slå ut dem.Syftet med denna rapport är inte att fastslå om man bör ha ett framtida elsystem med eller utan kärnkraft, utan att analysera grunderna, dvs kunskapsläget, för påståendet att det är nödvändigt att ha kärnkraft. Alla diskussioner om framtiden är osäkra, så vi gör heller inte anspråk på att förutse hur framtiden kommer se ut. Upplägget är att gå igenom olika frågeställningar, och koppla dessa till frågan om huruvida kärnkraften är nödvändig för framtiden, så som framförts med exempelvis följande argument:a) Kärnkraft behövs av ekonomiska skälb) Kärnkraft behövs för att vi inte ska vara importberoendec) Kärnkraft behövs eftersom det finns kapacitetsbrist i t ex Malmö och Stockholmd) Kärnkraft behövs för att klara elektrifieringen av transporterna och industrine) Kärnkraft behövs för att klara klimatmåletf) Kärnkraft behövs för att vi ska få el alla timmar, dvs klara leveranssäkerheteng) Kärnkraften behövs för att klara frekvensstabilitetenh) Kärnkraft behövs för stödtjänster till elsystemetI avsnitt 2-7 finns en genomgång av dagsläget. I avsnitt 8 finns en mer detaljerad genomgång av listan a)-h) ovan. Mer tekniska detaljer om systembalansering och effektbalansberäkningar finns i Bilaga A-C.Den slutsats vi drar är att kärnkraften inte är nödvändig för att vi ska kunna få ett stabilt, säkert och fossilfritt elsystem i Sverige i framtiden. Ett elsystem med stor mängd sol- och vindkraft ser dock annorlunda ut än ett med stor mängd kärnkraft. Frågan är då om detta system blir dyrare. Ingen vet vad olika kraftslag kommer att kosta år 2045, men under senare år har det skett en kraftig minskning av kostnaderna för sol- och vindkraft. Samtidigt har kärnkraftens kostnader istället ökat kraftigt. Den är nu betydligt dyrare än ny vindkraft.
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| 7. |
- Zetterberg, Lars, et al.
(author)
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Incentivizing BECCS - A Swedish Case Study
- 2021
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In: Frontiers in Climate. - : Frontiers Media SA. - 2624-9553. ; 3
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Journal article (peer-reviewed)abstract
- Negative carbon dioxide (CO2)-emissions are prevalent in most global emissions pathways that meet the Paris temperature targets and are a critical component for reaching net-zero emissions in Year 2050. However, economic incentives supporting commercialization and deployment of BioEnergy Carbon Capture and Storage (BECCS) are missing. This Policy and Practice Review discusses five different models for creating incentives and financing for BECCS, using Sweden as an example: (1) governmental guarantees for purchasing BECCS outcomes; (2) quota obligation on selected sectors to acquire BECCS outcomes; (3) allowing BECCS credits to compensate for hard-to-abate emissions within the EU ETS; (4) private entities for voluntary compensation; and (5) other states acting as buyers of BECCS outcomes to meet their mitigation targets under the Paris Agreement. We conclude that successful implementation of BECCS is likely to require a combination of several of the Policy Models, implemented in a sequential manner. The governmental guarantee model (Model 1) is likely to be required in the shorter term, so as to establish BECCS. Policy Models 2 and 3 may become more influential over time once BECCS has been established and accepted. Model 3 links BECCS to a large carbon-pricing regime with opportunities for cost-effectiveness and expanded financing. We conclude that Policy Models 4 and 5 are associated with high levels of uncertainty regarding the timing and volume of negative emissions that can be expected—Thus, they are unlikely to trigger BECCS implementation in the short term, although may have roles in the longer term. Based on this study, we recommend that policymakers carefully consider a policy sequencing approach that is predictable and sustainable over time, for which further analyses are required. It is not obvious how such sequencing can be arranged, as the capacities to implement the different Policy Models are vested in different organizations (national governments, EU, private firms). Furthermore, it is important that a BECCS policy is part of an integrated climate policy framework, in particular one that is in line with policies aimed at the mitigation of greenhouse gas (GHG) emissions and the creation of a circular economy. It will be important to ensure that BECCS and the associated biomass resource are not overexploited. A well-designed policy package should guarantee that BECCS is neither used to postpone the reduction of fossil fuel-based emissions nor overused in the short term as a niche business for “greenwashing” while not addressing fossil fuel emissions.
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