Increase In Levelized Cost Of Electricity Research Articles

Techno-economic evaluation of CO2 capture and storage retrofit in decarbonizing different thermal power plants: A case study in China

Given that thermal power plants are the dominant mode of power generation in China, decarbonization from thermal power plants is significant to protect the global climate from further warming. CO2 capture and storage (CCS) is one of the most promising approaches for mitigating CO2 emissions; therefore, studies evaluating the effect of CCS retrofit on thermal power plants are urgently required. This study selected coal-fired power plant (CFPP) and natural gas combined cycle power plant (NGCC) as the representative technologies for thermal power plants, and proposed system models for their integrations with CCS. A comprehensive evaluation system was established using different metrics such as specific CO2 emission (CO2 emission per kWh), net electric efficiency, levelized cost of electricity (LCOE), and cost of avoiding CO2 emission (COAE). The detailed effects of fuel price fluctuations, technological advances, and different technology combinations on key metrics were analyzed, in order to propose policy recommendations for the decarbonization of China's thermal power plants using CCS technology. The following results were obtained: (1) The use of CCS to reduce CO2 emissions from thermal power plants will lead to a significant increase in LCOE. Each 100 g/kWh reduction in specific CO2 emission will result in 11 %–14.5 % increase in LCOE for CFPP + CCS, and 9.5 %–13.5 % increase for NGCC + CCS. (2) Technological advances toward reducing specific heat consumption for CO2 capture should be strongly promoted to reduce LCOE. Each 0.4 GJ/t reduction in specific heat consumption will result in an approximately 0.066 CNY/kWh reduction in LCOE for CFPP. (3) Both CFPP + CCS and NGCC + CCS exhibit potential for decreasing COAE below 600 CNY/t, although the technologies to meet this threshold are not currently realistic at higher fuel prices.

A Kinetic Performance-Informed Technoeconomic Assessment-Life Cycle Assessment Model of Ce and V Redox Flow Batteries

The EIA projects that 60% of cumulative capacity additions in the U.S. by 2050 will be renewable electric generating technologies.1 The use of intermittent renewable energy in the U.S. electricity grid requires energy storage. NREL predicts that for a scenario in which 80% of electricity in the U.S. comes from renewable energy by 2050, 120 GW of energy storage would be needed,2 yet as of 2020, the U.S. has only 24 GW of storage capacity.3 Redox flow batteries (RFBs) are a useful technology for ensuring the smooth integration of renewable energy into the U.S. electricity grid because of their long lifecycles and discharge times. RFBs are currently too expensive for market deployment, however, with the all vanadium RFB (VRFB) costing double the DOE target.4,5 One way to improve the cost effectiveness of RFBs is to explore chemistries that increase the voltage window. The replacement of the VO2+/ VO2 + chemistry at the positive electrode of a VRFB with the Ce3+/Ce4+ chemistry would result in an increased theoretical voltage, but it is unclear how the kinetic, ohmic, and mass transport overvoltages would change. Additionally, studies of the environmental burdens of life cycle phases of Ce RFBs are limited. To advance the most cost effective and least environmentally harmful RFB, in this study, we develop a combined Technoeconomic Assessment-Life Cycle Assessment (TEA-LCA) model that is informed by our performance measurements to compare the levelized cost of electricity (LCOE) and levelized greenhouse gas (LGHG) emissions of VRFBs and Ce-V RFBs.The TEA-LCA model allows the user to select from a list of positive and negative electrode redox chemistries, solvents, electrode materials, and electricity grid generation profiles to calculate the LCOE and LGHG emissions of the battery for the delivery of 1 kWh of energy. A solver function optimizes the current density that minimizes either LCOE or LGHGs. The TEA-LCA model uses a bottom-up approach, in which energy- and power-dependent capital costs and environmental burdens are calculated by converting the amount of material to a kWh basis. Cost estimates are sourced from vendors and GHG emissions are pulled from the GREET database and literature. The amount of active species required to deliver 1 kWh of electricity at a specified discharge time is calculated using the redox couple properties, including redox potential, exchange current density, and limiting currents. These performance parameters are based on measurements collected in lab. The use phase burdens are calculated using the roundtrip efficiency of the battery and the price and GHGs associated with the electricity grid generation mix. End-of-life costs consist of the economic and environmental burdens of recycling and disposing of the battery material and are collected from vendors and GREET.The TEA-LCA model answers important questions related to the optimal operating conditions of an RFB. In addition to comparing the economic and environmental performances of the VRFB and Ce-V RFB, it demonstrates how different electricity grid mixes influence total cost and emissions and highlights the difference in optimal operating current density if cost or GHG emissions are prioritized, e.g., lower current density results in fewer emissions but higher cost in carbon-intensive electricity grid profiles. Preliminary results using literature values show that the Ce-V RFB has an LCOE that is 45% lower than the VRFB LCOE, with capital costs dominating. We will present the finalized LCOE for the VRFB and Ce-V RFB, as well as LGHGs, as a function of discharge time and electricity grid mix. Sensitivity analyses of the input parameters found that for both RFBs, the discount rate, discharge faradaic efficiency, and lifetime of battery had the most influence on LCOE, with a 20% decrease in discharge faradaic efficiency resulting in a 16% increase in LCOE for the VRFB. The results of this TEA-LCA model show that the use of cerium is a viable option for reducing the cost of RFBs to advance their use in renewable energy storage grid applications. Additionally, this model is generalizable to other batteries and electrochemical systems, such as CO2 conversion. Thus, the development of this TEA-LCA model represents not only an advancement to the field of redox flow batteries but also the wider field of electrochemistry. U.S. EIA. Annual Energy Outlook. (2021).Mai, T. et al. Renewable Electricity Futures Study. NREL. (2012).CSS University of Michigan. U. S. Grid Energy Storage Factsheet. (2021).Mongird, K. et al. 2020 Grid Energy Storage Technology Cost and Performance Assessment. (2020).Weber, A. Z. et al. J. Appl. Electrochem. 41, 1137–1164 (2011).Smith, G. F. & Getz, C. A. Ind. Eng. Chem. Res. 10, 191–195 (1938).

Development of sustainability indicators for the assessment of coal-based power generation pathways

This paper is to develop measurable indicators of coal-based power generation pathways to establish a benchmark for comparative sustainability assessment and optimization. Power generation from coal subdivided to thirty-six pathways with the development of two sets of sustainability indicators. The first set includes the complete life cycle, and the second set includes only the power generation stage. The complete life cycle covers coal mining, power generation, and cooling system unit operations. Comprehensive evaluation necessitates the development of five sustainability indicators to cover water demand (consumption and withdrawals), greenhouse gas emissions (GHG), land use, and levelized cost of electricity (LCOE). Compared to the conventional coal-based power generation technologies, new coal technology pathways have the lowest GHG emissions, use less water and land, but would have a different impact on the LCOE. The cooling system type is the factor with the most impact on the water demand indicators; coal combustion unit operation has the most impact on the GHG emissions indicator; dry cooling has the most impact on the LCOE indicator. The fuel production stage has the most impact on the land use indicator. The resources and GHG emissions-effective scenario conducted to cover the demand capacity range of 250–5000 MW. This scenario shows that due to the importation of coal from a different jurisdiction and based on the average values, the savings in water demand is 87%, the savings in land area is 95%, the mitigation of GHG emissions is 6%. In contrast, the corresponding average increase in LCOE is 14%.

Economic Analysis of WECSs Using LCOE and PVC Approaches in Northern Ethiopia

In this study, the relative economic contrast of wind energy conver-sion systems (WECSs) are examined using levelized cost of electricity(LCOE) and present value cost (PVC) as measures of merit of systemlife cycle cost. From the analysis of data and discussion, capacity factorand useful life of the wind turbine have a positive impact on the costof electricity produced by the WECS, while the other input parametersof LCOE and PVC increase the system life cycle cost, as their values in-creases. The trend of capacity factors decreased linearly, and the simul-taneous increase in LCOE and PVC was noticed.

Economic Analysis of WECSs Using LCOE and PVC Approaches in Northern Ethiopia

ABSTRACTIn this study, the relative economic contrast of wind energy conversion systems (WECSs) are examined using levelized cost of electricity (LCOE) and present value cost (PVC) as measures of merit of system life cycle cost. From the analysis of data and discussion, capacity factor and useful life of the wind turbine have a positive impact on the cost of electricity produced by the WECS, while the other input parameters of LCOE and PVC increase the system life cycle cost, as their values increases. The trend of capacity factors decreased linearly, and the simultaneous increase in LCOE and PVC was noticed.

Evaluation of Palladium-Based Sorbents for Trace Mercury Removal in Electricity Generation

The development of warm-gas cleanup (WGCU) systems for synthesis gas (syngas) cleanup in in- tegrated gasification combined cycle (IGCC) power plants has the potential to lower the costs of generating power. WGCU includes the removal of mercury (Hg), present in coal, from the syngas. Carbon-based sorbents used for Hg removal are not suitable for high-temperature Hg removal in conjunction with the WGCU. The US Department of Energy’s National Energy Technology Laboratory’s (DOE/NETL) Office of Research & Development (ORD) has been developing various sorbent alternatives to address the problem of high-temperature Hg removal. This study presents analysis of the capture of Hg from syngas streams as a polishing step to attain US Environmental Protection Agency (EPA) Mercury and Air Toxics Standards (MATS) requirements for Hg (0.003 lb/GWhgross for new IGCC plants) using palladium (Pd) adsorbent being tested by DOE/NETL in association with Johnson Matthey (JM). For the present study, it was assumed that syngas is already cleaned to 5 parts per billion by weight (ppbw) Hg, and the Pd sorbent technology is used as a polishing step to achieve the EPA MATS requirements (0.003 lb/GWhgross, equivalent to 2 ppbw given representative process configuration and material flows). The incremental cost of Hg polishing and the additional capital cost needed were estimated for several scenarios/cases. These cases were differentiated by variance in the following parameters, which are important because they have direct im- pacts on additional capital costs ($/kW), and in turn impacts on the levelized cost of electricity (LCOE): 1) Pd cost (varied from $4,000 to $12,000/lb Pd); 2) Gas hourly space velocity (SV) (varied from 500 to 13,500 h-1); 3) Pd loading (varied between 2 w/w% Pd and 5 w/w% Pd); 4) Sorbent make-up rate (varied between 3%, 1%). The ranges were chosen in order to reasonably reflect, in the cases that are analyzed, the actual fluctuations that have been observed in past *Corresponding author. experience in these important parameters that affect cost (e.g., the Pd cost has kept to within the $4 to 12 k/lb range in recent years). In the case of SV, the high and low points of the range are extremes beyond which costs would either be unreasonable, or increase in cost benefit would be negligible. For a typical case (i.e., using mid-range values of the parameters, including SV of 8000 h-1, 2% Pd loading, 3% make-up rate, $9500/lb Pd cost), the increase in LCOE due to the Pd-polishing system is approximately 0.4% and the additional capital cost is ~$10/kW. As a comparison, the incremental capital cost of conventional Hg removal in an IGCC plant is ~$4 to 8/kW, and the increase in the LCOE is less than 0.4%. Results indicate that in the range of SVs from 3500 h-1 to 10,000 h-1, the Hg-polishing step is expected to function adequately and with increase of LCOE limited to about 1% - 2%. The use of a Pd sorbent-based polishing system to reduce trace Hg levels to the EPA MATS requirements for new IGCC power generation appears to be feasible and reasonably cost-effective.

Post-combustion CO2 capture using super-hydrophobic, polyether ether ketone, hollow fiber membrane contactors

The feasibility of utilizing a super-hydrophobic polyether ether ketone (PEEK) hollow fiber membrane contactor in combination with chemical solvents to separate and capture CO2 from simulated flue gases was investigated. Greater than 90% CO2 capture with greater than 95% CO2 purity has been achieved in one stage with both activated methyldiethanolamine (aMDEA) and activated K2CO3 solvents. The measured volumetric mass transfer coefficient was as high as 1.7s−1, which is more than 20 times greater than the mass transfer coefficient of a packed column. Preliminary tests indicated that the CO2 capture performance was not affected by flue gas contaminants, including O2, NO2, and SO2, with aMDEA solvent. The PEEK membrane module showed good mechanical properties and stable permeation properties at process design conditions for duration of the test (120h). The process economics were evaluated assuming direct substitution of the conventional absorber by the membrane contactor, while using a conventional packed column in the regeneration step. Relative to the cost estimation with no CO2 capture, the evaluation indicates a 56% increase in the levelized cost of electricity (LCOE) for the PEEK membrane contactor technology, which is 29% lower than DOE’s benchmark amine absorption technology (85% increase in LCOE).