| 21. |
- Andersson, Klas, 1977, et al.
(författare)
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Radiation Intensity of Propane-Fired Oxy-Fuel Flames: Implications for Soot Formation
- 2008
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Ingår i: Energy & Fuels. ; 22:3, s. 1535-1541
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Tidskriftsartikel (refereegranskat)abstract
- The changes in the soot-related radiation intensity between two different oxy-fuel flames and an air-fired flame were investigated in a 100 kW oxy-fuel test unit firing propane. The oxy-fuel test cases with 21 and 27 vol % O2 in the recycled flue gas (RFG) were run with different amounts of dry RFG, which in principle only consisted of CO2 from combustion and some excess O2. The stoichiometric oxygen-to-fuel ratio was kept at 1.15 in all cases. Total radiation intensity was measured with a narrow angle radiometer. Temperature and gas composition measurements served as inputs to computations of gas radiation. A comparison of the computed gas radiation with the measured total radiation intensity enabled estimation of the radiation related to soot. Clear differences were observed in the amount of soot formed in the two oxy-fuel flames (also compared to the air flame). In the oxy-fuel flame with 21 vol % O2 in the RFG, soot formation is almost completely suppressed, but when the total flow through the burner is reduced by about 20% (by volume) (i.e., from 21 to 27 vol % O2 in the RFG), the amount of soot present in the flame becomes significant. This change in soot volume fraction affects the radiation emitted from the flames; images of the flames qualitatively confirm these differences in the flame luminosity. Thus, carbon dioxide not only increases the gas radiation, but it can also drastically influence soot formation and the radiation originating from soot during oxy-fuel combustion.
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| 22. |
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| 23. |
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| 24. |
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| 25. |
- Andersson, Klas, 1977, et al.
(författare)
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The CO2 avoidance cost of a large scale O2/CO2 power plant
- 2005
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Ingår i: Proceedings of the 7th International Conference on Greenhouse Gas Control Technologies 5– September 2004, Vancouver, Canada. ; , s. 1787-1790
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Konferensbidrag (refereegranskat)abstract
- This work evaluates the fixed and running costs together with the CO2 avoidance cost of an O2/CO2 combustion process. The work is based on a comprehensive process study applied to commercial process data from an 865 MWe lignite fired reference power plant and large scale air separation units (ASU), in combination, with a detailed design study of the flue gas treatment and CO2 compression train (FGTCC) [1]. All costs for the process layout proposed in [1] are gathered from industry. Although an existing reference power plant forms the basis of the work, the study is directed towards a new state-of-the-art lignite-fired O2/CO2 power plant.
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| 26. |
- Andersson, Klas, 1977, et al.
(författare)
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Thermal radiation in oxy-fuel flames
- 2011
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Ingår i: International Journal of Greenhouse Gas Control. - : Elsevier BV. - 1750-5836. ; 5:suppl. 1, s. S58-S65
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Tidskriftsartikel (refereegranskat)abstract
- This work investigates thermal radiation in oxy-fuel flames, based on experiments and modelling. Experiments were conducted in a 100 kW test facility in air and oxy-fuel combustion atmospheres, using two different types of fuels, lignite and propane. In-flame measurements of gas composition, temperature and total radiation intensity, were performed and used as input to radiation modelling to examine the influence of oxy-fuel conditions on gas and particle radiation characteristics. In the modelling, the spectral properties of CO(2) and H(2)O are treated by means of a statistical narrow band model and particle radiation is modelled for both scattering and non-scattering particles. Experiments on the propane flame show that the flame radiation conditions are drastically influenced by the recycling conditions. With OF 27 conditions (27% oxygen in the feed gas) and dry recycling, the temperature is slightly lower compared to air-fired conditions, but the emitted intensity is significantly increased. Modelling shows that this is mainly caused by a significantly increased soot radiation. Propane flame images show that the presence of soot in oxy-fuel conditions varies strongly with recycling conditions. The contribution due to an increased emission by CO(2) is of minor importance. In the lignite experiments similar flame temperatures were kept during air and oxy-fuel combustion (OF 25 conditions with dry recycling). The measurements show that the intensity levels in both flames are similar which is due to a strong particle radiation in both environments. The modelling reveals that the dominance by particle radiation contra gas radiation is closely related to whether the particles are scattering or non-scattering.
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| 27. |
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| 28. |
- Andersson, Sara-Linnea, et al.
(författare)
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Plug-in Hybrid Electric Vehicles as Regulating Power Providers - Case Studies of Sweden and Germany
- 2010
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Ingår i: Energy Policy. - : Elsevier BV. - 0301-4215. ; 38:6, s. 2751-2762
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Tidskriftsartikel (refereegranskat)abstract
- This study investigates plug-in hybrid electric vehicles (PHEVs) as providers of regulating power in the form of primary, secondary and tertiary frequency control. Previous studies have shown that PHEVs could generate substantial profits while providing ancillary services. This study investigates under what conditions PHEVs can generate revenues using actual market data, i.e. prices and activations of regulating power, from Sweden and Germany from four months in 2008. PHEV market participation is modelled for individual vehicles in a fleet subject to a simulated movement pattern. Costs for infrastructure and vehicle-to-grid equipment are not included in the analysis. The simulation results indicate that maximum average profits generated on the German markets are in the range 30–80 h per vehicle and month whereas the Swedish regulating power markets give no profit.In addition, an analysis is performed to identify strengths, weaknesses, opportunities, and threats (SWOT) of PHEVs as regulating power providers. Based on the simulation results and the SWOT analysis, characteristics for an ideal regulating power market for PHEVs are presented.
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| 29. |
- Antonis, Papaemmanouil, et al.
(författare)
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A cost-benefit analysis of transmission network reinforcement driven by generation capacity expansion
- 2010
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Ingår i: IEEE Power & Energy Society (PES) General Meeting 2010, Minneapolis, USA, July 25 - 29, 2010. - 9781424483570
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Konferensbidrag (refereegranskat)abstract
- This paper assesses the effects of the future European power generation system with strict CO2 emission reduction targets on the planning of cross-border interconnection lines. Results from a techno-economic energy systems model have been used as input to this work, regarding the development of the European power generation system until the year 2050, meeting the EU 2020 CO2 target and a 85% emissions reduction until the year 2050. A simplified UCTE power system model was developed in order to analyze how the cross-border interconnections in continental Europe are affected by the generation plans using an iterative method. The paper also attempts to identify the congestion points and proposes solutions based on nodal price modeling. A cost-benefit analysis (CBA) is used to evaluate the appropriate transmission planning strategy, with the costs being the long-term investment costs and the benefits being both the avoided environmental costs and the total congestion costs. The effects of new investments on the nodal prices are also studied. The results show that the profitability of the investments is influenced by the available production mix and the forecasted CO2 prices. The avoided congestion costs participate rather insignificantly in the CBA, which means that congestions are not relieved, showing that many interconnections are insufficient for nodal pricing market structure.
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| 30. |
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