| 1. |
- Möllersten, Kenneth, 1966-, et al.
(författare)
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Bioenergy with CO2 Removal and Disposal : An Approach to Negative CO2 Emissions in Energy Systems
- 2001
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- In this paper, we present results from studies on bioenergy systems with CO2 removal and disposal (BCRD). CO2 removal and disposal that could prevent CO2 from fuel combustion entering the atmosphere is usually discussed in connection to fossil fuels. Even with very efficient CO2 removal in fossil fuel-based systems, there will always be positive net CO2 emissions. We show, on the other hand, that BCRD enables energy utilisation with a clearly negative CO2 balance. We present the first preliminary results from an economic assessment of BCRD, and review studies on the economics of CO2 removal in fossil-based systems for further guidance in estimating BCRD costs. We conclude that co-firing biomass and coal with end-of-pipe scrubbing technology promises to be one cost-effective BCRD option in the short term. In the long-term, systems with integrated biomass gasification promise lower additional CO2 removal costs, and black liquor gasification in chemical pulp mills is a particularly promising niche. Swedish and global CO2 reductions potential of this technology are estimated. Finally, some important policy-relevant questions related to the potential of BCRD are raised.
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| 2. |
- Möllersten, Kenneth, 1966-, et al.
(författare)
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CO2 balances and mitigation costs of advanced CHP systems with CO2 capture in pulp and paper mills
- 2003
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Konferensbidrag (refereegranskat)abstract
- This paper investigates the energy efficiency, CO2 mitigation potential and CO2 mitigation cost of biomass-based combined heat and power production (CHP) with a CO2 capture option in Kraft pulp and paper mills. CHP systems based on black liquor and biomass gasifier with combined cycle technology and biomass boiler with steam turbine technology are considered. The study shows that steep CO2 reductions can be achieved through CO2 capture and storage regardless of CHP technology used although alternatives based on black liquor and biomass gasification provide the most efficient systems from a resource and energy point of view. Moreover, using black liquor and biomass gasification technology both pulp mills and integrated pulp and paper mills can potentially become net electricity exporters while at the same time removing CO2 from the atmosphere on a net basis. Furthermore, cost curves are constructed, which show how the cost of CO2 capture and storage in pulp and paper mills depends on system configuration and the distance that the CO2 must be transported to injection sites. The assessment shows that systems based on black liquor and biomass gasification with CO2 capture in integrated pulp and paper mills remove CO2 most cost-effectively.
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| 3. |
- Möllersten, Kenneth, 1966-, et al.
(författare)
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Comparative assessment of industrial energy systems with negative CO2 emissions : Black liquor-based CHP with CO2 removal
- 2002
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Konferensbidrag (refereegranskat)abstract
- This paper investigates power production and CO2 reduction potentials of alternative systems for black liquorbasedcombined heat and power production (CHP) in pulp mills. The impact of incorporating CO2 removal inthe CHP systems is analysed. Spent cooking liquor in chemical pulp mills is an important source of bioenergy.Biomass energy with CO2 removal and disposal can yield negative CO2 emissions because the CO2 disposedof comes from biomass - i.e. CO2 can be removed from the atmosphere on a net basis while energy needs aresustained. We compare heat, power, and CO2 balances of systems with (1) alternative CO2-removal options(2) different systems for CHP. In relation to (1) we study CO2 removal with or without enhancing the CO2removal through reacting carbon monoxide with water (water-gas shift). The study reveals that black liquorgasification CHP with CO2 removal and disposal is an effective approach for CO2 reductions from bothenergy and environmental points of view.
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| 4. |
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| 5. |
- Möllersten, Kenneth, 1966-, et al.
(författare)
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Potential and cost-effectiveness of CO2-reducing measures in the pulp and paper industry
- 2001
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Ingår i: Proceedings of the Fifth International Conference on Greenhouse Gas Control Technologies. - Collingwood, Vic..
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Konferensbidrag (refereegranskat)abstract
- Using the two criteria of potential CO2 reduction and cost of CO2 reduction several technical options in the pulp and paper industry are investigated. Principal CO2 reducing measures include: decreasing fuel consumption through improved heat exchanging or new processes with lower heat demand, decreasing electricity consumption, substituting fossil fuels with biofuels, exporting refined biofuels for external use, increasing CO2 neutral electricity generation, improving waste heat utilisation and decreasing specific raw material consumption. The results show that electricity conservation and improvement of existing steam power cycles are the most cost-effective options that have a large potential to reduce CO2 emissions. Outsourcing of industrial energy operations to utilities may enable CO2 reducing measures that would not be carried out by industry due to differences in demands for profit on spent capital.
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| 6. |
- Möllersten, Kenneth, 1966-, et al.
(författare)
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Potential market niches for biomass energy with CO2 capture and storage : Opportunities for energy supply with negative CO2 emissions
- 2003
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Ingår i: Biomass and Bioenergy. - : Elsevier BV. - 0961-9534 .- 1873-2909. ; 25:3, s. 273-285
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Tidskriftsartikel (refereegranskat)abstract
- The paper presents an analysis of biomass energy with CO2 capture and storage (BECS) in industrial applications. Sugar cane-based ethanol mills and chemical pulp mills are identified as market niches with promising prospects for BEGS. Calculations of CO2 balances of BECS in these applications show that the introduction of CO2 capture and storage in biomass energy systems can significantly increase the systems' CO2 abatement potentials. CO2 emissions of the total systems are negative. The CO2 reduction potentials of these technologies are discussed in regional and global contexts. An economic assessment of each system is carried out and opportunities for cost-effective technologies for CO2 capture, transportation and storage are identified. Furthermore, potentials for system improvements that could substantially decrease the CO2 abatement cost are addressed.
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| 7. |
- Obersteiner, M., et al.
(författare)
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Managing climate risk
- 2001
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Ingår i: Science magazine. - Washington DC : American Association for the Advancement of Science (AAAS). - 0036-8075 .- 1095-9203. ; 294:5543, s. 786-787
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Tidskriftsartikel (refereegranskat)abstract
- Stabilization of atmospheric greenhouse gas (GHG) concentrations at a safe level is a paradigm that the scientific andpolicy communities have widely adopted for addressing the problem of climate change. However, aiming to stabilize concentrations at a single target level might not be a robust strategy, given that the environment is extremely uncertain. The availability of technological options for adaptation, preventive mitigation, and backstop risk measures will be critical for limiting the risks associated with climate change. Technologies that can rapidly remove GHGs from the atmosphere will play an important role. Terrestrial sinks are limited by land requirements and saturation, and concerns about permanence limit their attractiveness. Biomass energy can be used both to produce carbon neutral energy carriers, e.g., electricity and hydrogen, and at the same time offer a permanent CO2 sink by capturing carbon from the biomass at the conversion facility and permanently storing it in geological formations. It is concluded that a system of climate risk management is practicable and necessary. Increasing deployment of sustainable bioenergy with carbon removal and sequestration, together with structural shift toward low carbon-intensive fuels, will turn out to be instrumental for such a risk-limiting regime.
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| 8. |
- Obersteiner, Michael, 1967-, et al.
(författare)
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Managing Climate Risk
- 2001
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- At the heart of the traditional approach to strategy in the climate change dilemma liesthe assumption that the global community, by applying a set of powerful analyticaltools, can predict the future of climate change accurately enough to choose a clearstrategic direction for it. We claim that this approach might involve underestimatinguncertainty in order to lay out a vision of future events sufficiently precise to becaptured in a discounted cost flow analysis in integrated assessment models. However,since the future of climate change is truly uncertain, this approach might at best bemarginally helpful and at worst downright dangerous: underestimating uncertainty canlead to strategies that do not defend the world against unexpected and sometimes evencatastrophic threats. Another danger lies on the other extreme: if the global communitycan not find a strategy that works under traditional analysis or if uncertainties are toolarge that clear messages are absent, they may abandon the analytical rigor of theirplanning process altogether and base their decisions on good instinct and consensus ofsome future process that is easy to agree upon.In this paper, we try to outline a system to derive strategic decisions under uncertaintyfor the climate change dilemma. What follows is a framework for determining the levelof uncertainty surrounding strategic decisions and for tailoring strategy to thatuncertainty.Our core argument is that a robust strategy towards climate change involves thebuilding of a technological portfolio of mitigation and adaptation measures that includessufficient opposite technological positions to the underlying baseline emission scenariosgiven the uncertainties of the entire physical and socioeconomic system in place. In thecase of mitigation, opposite technological positions with the highest leverage areparticular types of sinks. A robust climate risk management portfolio can only workwhen the opposite technological positions are readily available when needed andtherefore they have to be prepared in advance. It is precisely the flexibility of thesetechnological options which has to be quantified under the perspective of the uncertainnature of the underlying system and compared to the cost of creating these options,rather than comparing their cost with expected losses in a net present value typeanalysis. We conclude that climate policy ― especially under the consideration of theprecautionary principle ― would look much different if uncertainties would be takenexplicitly into account.
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