Power Generation Sector Research Articles

Potential for Electric Vehicle Adoption to Mitigate Extreme Air Quality Events in China

Electric vehicle (EV) adoption promises potential air pollutant and greenhouse gas (GHG) reduction co-benefits. As such, China has aggressively incentivized EV adoption, however much remains unknown with regard to EVs’ mitigation potential, including optimal vehicle type prioritization, power generation contingencies, effects of Clean Air regulations, and the ability of EVs to reduce acute impacts of extreme air quality events. Here, we present a suite of scenarios with a chemistry transport model that assess the potential co-benefits of EVs during an extreme winter air quality event. We find that regardless of power generation source, heavy-duty vehicle (HDV) electrification consistently improves air quality in terms of NO2 and fine particulate matter (PM2.5), potentially avoiding 562 deaths due to acute pollutant exposure during the infamous January 2013 pollution episode (~1% of total premature mortality). However, HDV electrification does not reduce GHG emissions without enhanced emission-free electricity generation. In contrast, due to differing emission profiles, light-duty vehicle (LDV) electrification in China consistently reduces GHG emissions (~2 Mt CO2), but results in fewer air quality and human health improvements (145 avoided deaths). The calculated economic impacts for human health endpoints and CO2 reductions for LDV electrification are nearly double those of HDV electrification in present-day (155M vs. 87M US$), but are within ~25% when enhanced emission-free generation is used to power them. Overall, we find only a modest benefit for EVs to ameliorate severe wintertime pollution events, and that continued emission reductions in the power generation sector will have the greatest human health and economic benefits.

Renewable Power Generation: A Supply Chain Perspective

In recent years, the transition to a more sustainable and clean system has focused on the accelerated development of renewable energy technologies. This transition can be perceived as a major priority, especially with the current environmental concerns, threatening various aspects of human life. The objective of this article is, therefore, to highlight the role of the supply chain in the renewable power generation sector. In this context, a detailed assessment of the supply chain contribution to the renewable energy sector is presented. Next, the performance of the renewable energy supply chain is qualitatively evaluated by illustrating the various barriers against continuing development, and the key measures are recommended to overcome these barriers. Then, the main factors influencing the performance of the supply chain are identified and key performance indicators related to the renewable energy supply chain are established to achieve high efficiency and sustainability performances in the power sector.

Artificial neural network modeling for predicting the screening efficiency of coal with varying moisture content in the vibrating screen

ABSTRACT In India, coal is one of the prime sources of energy used in the power generation and metallurgy sector. The processing of coal below 3 mm is not successfully carried out in India. The quality of coal below 3 mm can be improved by decreasing the coal’s particle size, which reduces the ash percentage of coal. Screening is one of the significant beneficiation techniques used to reduce the size fraction of coal. The difficult to process coal of size −3 + 1 mm was selected in the present work. In this work, an attempt has been made to screen the coal of size −2 + 1 mm from −3 + 1 mm using a 2 mm screen mesh in the vibrating screen generated at different moisture content, angle, and frequency of the deck. The performance of the vibrating screen was evaluated using screening efficiency. Furthermore, prediction using a feed backward artificial neural network (ANN) model was developed on the experimental results for ten different neuron conditions. From the results, it was clear that the prediction results obtained from the ANN model were in good correlation with the experimental results.

Detailed analysis of power generation and water desalination sector emissions-part 1: criteria pollutants and BTEX

Based on 2016 fuel consumption and utilizing US-EPA AP-42 emission factors, emissions from the burning fuel facilities for energy production in Kuwait were calculated. The total emissions for criteria pollutants were 1.89E+01, 6.97E+02, 1.05E+02, 8.05E+00, 8.54E+00, and 1.60E−03 Gg of CO, SO2, NOx, PM10, PM2.5, and Pb, respectively. For benzene, ethylbenzene, toluene, xylenes, and BTEX, they were 2.27E−03, 3.11E−03, 1.91E−02, 6.21E−03, and 3.07E−02 Gg, respectively. In addition to ranking the power plants based on emission quantities, the ratio of the mass emitted from each compound to the released thermal energy (R) was calculated. The significance of R is that a power plant with a higher R value is considered to have more polluting effect if it was to have the same amount of thermal released energy. This concept was further extended to calculate the fuel-specific R using a system of 4 simultaneous equations. Zour South Power Station (PS) contributed most toward CO, SO2, and Pb emissions, while Sabiya PS had contributed most to NOx, PM10, and PM2.5 emissions. Boilers had the highest contribution to CO, SO2, NOx and Pb emissions, while gas turbines’ emissions of PM10 and PM2.5 exceeded those from boilers. Burning heavy fuel oil resulted in 89%, 90%, and 43% of the SO2, Pb, and NOx emissions. Gas oil contributed to 72% of CO emissions, while natural gas contributed to over 90% of PM10 and PM2.5 emissions. Shuwaikh Desalination Plant, which is about 1 km from urban areas, had the lowest contribution to BTEX and criteria pollutant emissions.

Deep reinforcement learning optimization framework for a power generation plant considering performance and environmental issues

In the electric power generation sector, striking a balance between maximum power production and acceptable emission limits is a challenging task that requires sophisticated techniques. With traditional methods, this is an extremely complex issue due to the large number of process variables that are involved. In this paper, a deep reinforcement learning optimization framework (DRLOF) is proposed to determine the optimal operating conditions for a commercial circulating fluidized bed (CFB) power plant that strikes a good balance between performance and environmental issues. The DRLOF included the CFB as an environment created from over 1.5 years of plant data with a 1 min sampling time which interacted with an advantage actor-critic (A2C) agent of two architectures named ‘separate-A2CN’ and ‘shared-A2CN’. The framework was optimized by maximizing electric power generation within the constraints of the plant’s capacity and environmental emission standards, taking into consideration the cost of operations. After training, the framework of the separate-A2CN architecture achieved a 1.97% increase in electricity generation and 1.59% emission reduction for NOx at 14.3 times lower computational cost. Furthermore, we demonstrated the framework’s flexibility, adaptability and lower computational burden by carrying out different test scenarios which demonstrated the effectiveness of the DRLOF. The findings of this study are not limited to the CFB power plant but can be extended to other chemical processes and industries. This approach minimizes the need for costly experiments, online optimization challenges and associated customizations. • Multi-objective optimization of CFB power plant with deep reinforcement learning. • Objective formulation considered power, fuel, reagent and environmental standards. • Two main reinforcement learning architectures were analysed for better CFB results. • Improved performance of CFB by 1.97% power increase and 1.59% emission reduction. • The framework’s generality, adaptability and computational efficiency were tested.

Decomposing CO2 emission changes in thermal power sector: A modified production-theoretical approach

Carbon emission from the thermal power generation sector is one of the main contributors to global warming. It is critical to objectively evaluate the influence of relevant factors on carbon emissions, which may be beneficial for the implementation of policies and the formulation of development plans. However, the current decomposition approach based on production-theoretical decomposition analysis (PDA) and weak disposability may cause deviation on potential emission reduction. This paper proposes a modified PDA model under the assumption of semi-disposability and decomposes the carbon emission changes of China's thermal power generation sector accordingly. The results show that provinces, which have the highest non-disposal degrees during the study period, are mostly located along the east coast of China. The growth in installed capacity is identified as the largest contributor to the increase in national carbon emissions, while the decrease in capacity utilization rate significantly benefits the carbon emission reduction. A cluster analysis is also conducted to give policy implications for provinces with similar characteristics. Compared with traditional methods under strong and weak disposability assumption, the proposed model shows great advantages in identifying the potential emission reduction and reflecting the real production process, which makes it more suitable for decomposing the changes of carbon emissions and other environmental pollutants.

Energy analysis and water conservation measures by water audit at thermal power stations

Water and energy are sources to fulfill the essential needs of human life for their livelihood. Currently, steam-based power plants utilize water sources such as rivers and lakes. In India, the consumption of water by industries is about 9% of the total, of which power generation sector utilizes 88% of the share. This study examines the quantitative and qualitative analysis of water consumption in power plants to determine the energy losses and water conservation opportunities to reduce, reuse, and recycle water. A typical water audit case study was carried out at specific coal-based Super Thermal Power Station (STPS) in India. The STPS chosen for the study has a commissioned capacity of 3000 MW having three stages of 1 GW each with a total of 6 units having 500 MW each. The present study includes the analysis of overall specific consumption of the plant, ash–water ratio, and cycles of concentration along with the blowdown water quantity along with other water losses. Also, exergy analysis of main water pumps is included, which is ranging from 46 to 67% for Stage-I. Based on the flow and power measurements and overall review of water consumption in the plant water and energy conservation opportunities are suggested which can yield savings up to INR 725.43 lakhs per annum INR (Indian Rupees) with an investment of INR 457 lakhs per annum expecting the payback period to be within a year.

China's Unconventional Carbon Emissions Trading Market: The Impact of a Rate-Based Cap in the Power Generation Sector

China's Unconventional Carbon Emissions Trading Market: The Impact of a Rate-Based Cap in the Power Generation Sector

The effect of transmission and distribution losses on daily electricity supply in Ebonyi State, Nigeria

It has been reported that Nigeria requires a daily generation of 470,000 MWH (or 19,583 MWH/H) to provide constant electricity to its 36 states and its capital city and is currently generating only 17% of the electricity required to meet the demands of her citizens. However, little or no in-depth analysis has been performed on the performance of the electricity transmission and distribution systems and to determine their impact on the availability of electricity for consumers. This paper explores the effect of transmission and distribution losses on the availability of electricity in Nigeria. The Nigerian National Electricity Grid was able to provide an average of 9.99 ± 0.54 hrs of electricity to the 13 LGAs of Ebonyi State for each day in July 2020. For the case where there were no transmission losses, each LGA in Ebonyi State would have received 10.79 ± 0.58 hrs of electricity each day in July 2020. Where no distribution losses were present, each LGA in Ebonyi State would have received 23.23 ± 1.25 hrs of electricity each day in July 2020. Where there were no transmission or distribution losses, each LGA in Ebonyi State would have received 25.09 ± 1.35 hrs of electricity each day in July 2020. These results indicate that elimination of the distribution losses presently experienced by the electricity distribution companies could ensure constant electricity supply for the 13 LGAs in Ebonyi State. Based on this, the power distribution sector, and not the power generation sector, is the major reason for the electricity shortage in Ebonyi State, and possibly for other states in Nigeria. It is recommended that more emphasis should be on distribution infrastructure now before focusing on improving the country's power generation capacity.

Dynamic Input Output Analysis: Carbon, Water and Ecological Hierarchy

As the main component of greenhouse gases, excessive carbon emissions are responsible for global climate change and anomalies. Carbon emission metabolism is essential for alleviating climate changes globally. Here, a dynamic input-output model is developed for analyzing carbon emission metabolism and ecological hierarchy. Direct and indirect carbon emissions are evaluated, and mutual relationships between various sectors are explored. The innovation of this research is summarized as follows: firstly, for carbon emission, the competition relationships reveal good interactions in terms of emission reduction while mutualism relationship provides effective pathways to mitigate carbon emissions between pairwise sectors simultaneously. Moreover, analysis of direct and indirect carbon emissions could help to extract embodied sectors with large emissions and identify whether the sectors should adjust their production structure or upgrade the clean combustion technology. In addition, ecological hierarchy analysis would help to identify key sectors lacking driving or pulling force during study period. It provides a new insight into the potential sectors which play an important role in the emission reduction. Results show that carbon emissions mainly concentrated in electricity-generation, manufacturing, and transportation sectors. In Guangdong province, upgrading the clean combustion technology in electric power generation and energy extraction sectors would drive other sectors to cut emissions and adjusting the production structure of the construction sector also contribute to achieve this goal. Tertiary industry is not sufficiently promoting Guangdong’s economic development, and therefore plays a restrictive role in the current economy. Results could help decision makers to develop emission mitigation policies.

Assessment of return and volatility spillover across sectors indices: evidence from Pakistan stock exchange

This paper examines the dynamics of return and volatility transmission between several sectors of Pakistan Stock Exchange (PSX). We employed GARCH(1,1) model and our results demonstrate that the most influential sector regarding the return spillover is power generation and distribution sector, and regarding volatility spillover, highly influential sector is automobile sector indicating that these sectors are the main drivers of spillover effect. Whereas, the most suggested sectors for investment are Automobile Assembler and Power generation and distribution sectors, as these are least influenced by other sectors' spillover. The investors and portfolio managers can use such findings as a guideline in making a healthy portfolio resulting in reduced risk to their investment. The well-informed decisions of the investors can, in turn, facilitate the growth of economy.

A New Enhanced Gas Recovery Scheme Using Carbonated Water and Supercritical CO <sub>2</sub>

The transition for clean, efficient, reliable, and affordable sources of energy is one of the top challenges of this century. Despite significant advances in renewable energies such as solar and wind, fossil fuels will remain a primary source of energy for years to come. Natural gas, fueling power generation and other vital industrial sectors such as desalination, is expected to play a more prominent role in the energy mix for many countries around the world. The demand for natural gas, especially in the Middle East, is on the rise. With the shortfall in recurrent discoveries of conventional gas resources, improving the recovery factors from legacy gas reservoirs is crucial. On the other hand, burning gas, like other fossil fuels, is associated with significant greenhouse gas emissions that should be mitigated, which is critical to comply with the pressing call for low-emission economies. CO2 injection in gas reservoirs is appealing as it may provide a dual benefit, including enhanced gas recovery (EGR), and partial entrapment of CO2 in the subsurface reservoir. Different CO2-EGR recovery schemes have been studied in the literature and showed that key thermodynamic properties of CO2, such as its high viscosity and density at reservoir conditions, make CO2 an efficient displacing fluid for the hydrocarbon gas. On the one hand, injecting CO2 can maintain the reservoir pressure by providing voidage replacement amid gas production. On the other hand, it can displace and mobilize the gas in place towards the production wells; nonetheless, CO2-EGR may not be economically viable. The main drawback of CO2 injection is the relatively rapid breakthrough at the production wells leading to gas recovery inefficiency due to CO2 separation and recycling. This pre-mature breakthrough of CO2 is driven by CO2/gas dilution from mechanical mixing, dispersion, and molecular diffusion. Producing gas with high impurity because of CO2 mixing adds significant CAPEX and OPEX related to the surface facilities and gas treatment, especially for fields whose initial content of CO2 within the gas composition is negligible. In this work, we propose a CO2-based EGR scheme that involves two stages. The first stage corresponds to the situation when the reservoir pressure is below that CO2 bubble point pressure. At this condition, CO2 will be in the gas state, and therefore, its sweep and displacement efficiency will be poor owing to its low viscosity and density. At this stage, CO2/gas mixing will be pronounced, and CO2 mobility will be high, leading to an early breakthrough. To avoid this unfavorable situation, we propose to co-inject brine and CO2 (carbonated water) in which CO2 will be in the aqueous solution and non-buoyant. As the carbonated water is heavier than the in-situ brine, CO2 remains trapped in the aqueous phase and flows down-dip towards the bottom of the reservoir. In stage 2, CO2 is injected in its dense supercritical phase, where the presence of water reduces its mobility and delays its breakthrough time. This two-stage injection process is more efficient than the traditional continuous CO2 injection. We demonstrate the effectiveness of this recovery scheme for a synthetic model mimicking an actual gas field. We analyze the optimum transition conditions from stage 1 to stage 2 and show a significant incremental recovery and CO2 entrapment compared to the traditional CO2-EGR that relies on continuous CO2 injection. This proposed scheme serves both objectives, which are an efficient EGR and optimum CO2 sequestration resulting from delayed CO2 breakthrough. We believe that this scheme provides significant improvements to the traditional CO2-EGR and has the features to be deployed at the field scale.

Incentives for Vertically Integrated Firms in the Natural Gas and Electricity Markets to Manipulate Prices

This paper examines the potential for vertically integrated firms that own assets in both the natural gas and electricity markets to manipulate natural gas and electricity prices through the withholding of natural gas pipeline capacity. An integrated firm theoretically could increase the price it receives in the electricity market by withholding pipeline capacity to the wholesale natural gas market, thereby reducing wholesale supply of natural gas and potentially increasing generation costs for electricity through higher natural gas prices. A key criteria in assessing whether an integrated firm’s allocation of pipeline capacity between the wholesale and retail markets constitutes manipulation relates to whether the allocation is profit maximizing on a stand-alone basis, i.e., the allocation maximizes the firm’s profits in the natural gas market without considering its profits in the electricity market. I develop a theoretical model that examines the incentives to allocate pipeline capacity to the wholesale natural gas market, which supplies the power generation sector, and the retail natural gas market. I find that an integrated firm may choose to allocate more pipeline capacity to the retail market than the wholesale market in order to reduce the probability of paying fines from failing to adequately meet retail demand, to increase its profits in the wholesale natural gas market, or to increase its profits in the electricity market. In order to prove a manipulation has occurred, it must be shown that the last case is true and the first two cases had little effect on the allocation decision.

AHP기법을 통한 EPC기업의 프로젝트 핵심성공프로세스 개발

Purpose By developing the key success processes of the projects of domestic EPC companies participating in overseas power generation and petrochemical projects and presenting them to academics and industry, it will contribute to the study of project management and improve the international competitiveness by enhancing the project execution capability of domestic EPC companies. Methods The research method is to compare the proportion of each process to 49 processes functions in 10 knowledge areas and 5 process groups presented by PMBOK 6th edition by a group of experts with more than 20 years of experience in the representative plant EPC companies in Korea. After collecting expert opinion analysis data, we used the Analytic Hierarchy Process (AHP) technique and tiered and prioritized for each stage of project execution. Results The existing qualitative method is quantitatively analyzed to determine priorities for key success factors of project management and methodology accordingly. Conclusion By prioritizing the detailed elements of the EPC project management process in the overseas power generation and petrochemical sectors, we present strategic directions for the execution of overseas projects by domestic EPC companies.

Techno-economic and environmental implications of decarbonization process applied for Romanian fossil-based power generation sector

This study estimates the technical, economic and environmental impact of decarbonization strategy on Romanian fossil power generation sector. Two post-combustion decarbonization options are considered either for existing power plant retrofit or new investment based on current conventional designs: a technological and commercial mature chemical scrubbing process using methyl-diethanol-amine (MDEA) and one more innovative and energy-efficient gas-solid process using calcium looping (CaL). Considering the Romanian power generation sector conditions, natural gas, hard coal and lignite were assessed as fuels. The decarbonized designs have 1000 MW net electricity output to permit an easier scale-up calculation with 90% CO2 capture rate. The non-decarbonized designs are also assessed to quantify the decarbonization energy and economic costs. It was shown that the decarbonization of Romanian fossil-fired electricity plants has significant benefits in term of increasing overall energy efficiency (from current 30–33% for coal and lignite and 35–39% for natural gas to 32.5–36% and 48–52% respectively) as well as reducing the cost of electricity (from current 80–120 €/MWh to 55–85 €/MWh). The investment effort to replace all fossil fleet (both gas and coal) with new modern units is foreseen to be substantial (about 11.2–14.9 billion Euro). A detailed environmental analysis was provided to assess the overall impact of decarbonization.

Analysis of Thermally Induced Breakup of Ultrasonically Emulsified Heavy Fuel Oil using Dynamic Mode Decomposition

Clean and efficient processing of heavy fuels is a major challenge for several combustion driven prime movers like internal combustion engines, used in marine or power generation sectors. Emulsification was recognized in the past as practical technology for heavy fuels combustion since it engenders an enabling phenomenon called micro-explosion that proceeds during the spray process. Micro-explosions allow finer secondary break-up, leading to improved mixing, and subsequent cleaner and fuller burning. However, the translation of this technology to real applications is still not fully exploited due to lack of basic understanding and characterization of the evaporation process which includes both micro-explosions and puffing. Ultrasonically induced cavitation is a promising technology for the production of water-in-oil emulsions at industrial scale. Fundamental research performed in the field of liquid fuels gasification and combustion mostly regards ideal or simple mixtures and not all the considerations made in these cases apply for real fuels. In this work, we investigated the evaporation characteristics of ultrasonically produced heavy fuel oil (HFO) emulsions with a set of newly developed methodologies. We characterized the emulsions by using a state-of-the-art microscopy technique, the Cryogenic Scanning Electron Microscopy, Cryo- SEM and obtained accurate droplet size distribution up to nano-scale. We tested the fuel emulsion in a suspended droplet experiment and reconstructed the interface from the obtained images. The normalized squared diameter profile is not representative of the complex physics involved in heavy fuel evaporation; therefore, it was substituted with the normalized distance of the interface from the centroid of the droplet. By using this procedure, it is possible to highlight both evaporation and stochastic events like puffing and ejections. A dimensionality reduction algorithm, the dynamic mode decomposition (DMD), was then performed on the evolving interface to highlight the main modes describing the emulsion system and the dynamics. The overall objective was to develop a strategy for optimizing emulsions for improved combustion performance. From the experimental data, it was observed that a water concentration of 5% by mass decreases the vaporization time of the mixture and that the presence of water favors puffing and ejections with different intensity depending on the percentage of water enhancing the volatilization of the fuel.

Dynamic Data Envelopment Analysis Model Involving Undesirable Outputs in the Electricity Power Generation Sector: The Case of Latin America and the Caribbean Countries

Studying the evolution of the efficiency of the electricity generation sector is a relevant task for policy makers, and requires the undesirable outputs derived from the activity to be considered in the evaluation. In this work, we propose a dynamic slack-based Data Envelopment Analysis (DEA) model that incorporates the assumption of weak disposability between the generation of electricity from fossil sources and the CO2 emissions caused by the sector to measure the technical efficiency of 24 Latin American and Caribbean countries in the period 2000–2016. The results show that, of the total number of countries studied, four are efficient overall, and four groupings of countries in relation to the levels of efficiency achieved are also identified. These results are important given that less-efficient countries can, through learning, increase their efficiency in electricity generation or emulate the future strategies proposed by the most efficient countries.

When extractive political institutions affect public-private partnerships: Empirical evidence from Indonesia's independent power producers under two political regimes*

This paper examines how extractive political institutions are associated with the performance of public-private partnerships (PPPs) using the case of the electricity sector in Indonesia, where a political regime shift has impacted the independent power producers’ (IPPs) arrangements in the power generation sector. Using a two-stage empirical strategy (data envelopment analysis and the difference-in-differences regression), I analyzed the economic performance of 20 coal-fired plants for the period between 2010 and 2016 that consists of IPPs endorsed by the two political regimes, both authoritarian and democratic, and the state-owned power plants. The results indicate that the extractive political institutions are associated with a reduced efficiency of the IPPs endorsed by the authoritarian Soeharto regime by −0.135 points, or 0.16% of the mean, showing that across all other power plants that produced the same output, the plants endorsed by the Soeharto regime used input or expenditure 0.16% higher than the average input or expenditure used by other plants. These findings are consistent with the political economy argument that extractive political institutions might have created economic policies that allow for the political elite to extract rents from PPPs.

Evaluation of Energy Transition Pathways to Phase out Coal for District Heating in Berlin

As Germany struggles to meet its near-term emissions reduction targets in lagging sectors like heating or transport, the need to identify energy transition pathways beyond power generation is urgent. This paper presents an investigation of tangible and climate-friendly transformation paths to replace the existing coal-fired units used for heat and power generation in Berlin with a largely CO2-free innovative technology mix. Although the literature has extensively covered the decarbonization of the power generation sector on different geographic scales, few studies have focused on the decarbonization of the heat sector in cities with large district heating networks, like Berlin. This paper aims to fill this gap. The proposed methodology combines three key elements: (1) scenario analysis including high-fidelity models of the European power market and the heat demand in Berlin, (2) evaluation of energy potential from low-carbon alternative sources, and (3) a techno-economic portfolio optimization. The results suggest that a coal phase-out by 2030 is feasible without any discontinuities in the provision of heat. Although low-carbon sources could partially substitute coal-based heat, they would not be sufficient to replace it completely. Thus, a gas-based hydrogen-ready combined heat and power plant linked with a power-to-heat plant would be required to fill the gap.

A REVIEW ON RENEWABLE ENERGY INTEGRATION FOR ELECTRIC VEHICLES

Electric vehicles (EVs) or renewable energy (RE) sources provide the potential to significantly reduce emissions of carbon as of the economy's transport & power generation sectors. There can be a range of impacts and benefits to the mass adoption of EVs, with the ability to aid in integrating renewable energy into current electricity grids. Present literature on EVs, power grid as well as the integration of RE is reviewed in this paper. Literature’s main methods and assumptions are deliberated. Economic, environmental & the grid effects of EVs are studied. Several research studies have been conducted on the ability of EVs to integrate Res. literature indicates that excess RE generated on a power grid can be reduced significantly. In the Vehicle to grid (V2G) idea the Plug-in electric vehicle (PEVs) can be performed as the load or as the distribution energy source. By using the V2G idea the performance of the electricity grid will increases. The efficiency, stability & reliability will increase.