Central versus wellhead power plants in geothermal grid electricity generation

Abstract

The long gestation period, high upfront costs and the risks in the development of central geothermal power plants are the main reasons for the slow rate of geothermal electricity growth and its contribution to the global electricity mix. The overall objective of this study was to make a comparison between central geothermal power plants and wellhead power plants in the delivery of geothermal electricity projects. The study showed that wellhead power plants are generally less efficient compared to central power plants because of higher specific steam consumption, but are financially attractive because of the quicker return on investment, early electricity generation and the lower financial risks. The study showed that permanent wellhead power plants are a better option for geothermal wells with too low or too high steam pressure compared to others in the steam field. Temporary use of wellhead power plants as opposed to their permanent use is preferred when only limited time is available between the commissioning of a wellhead plant and the commissioning of a central power plant in the same steam field. Technical, operational and environmental challenges, including higher specific steam consumption and lower efficiency than central power plants as well as absence of geothermal fluid reinjection system make wellhead plants less economical and less sustainable in resource use. It can thus be concluded that wellhead power plants can reduce the long wait to generate geothermal electricity and make an early return on investment for investors. Both central and wellhead power plants have relatively higher capacity factor than many other power plants and so can be used to supply base load electricity for the grid or off-grid power supply. This study is a review of the central and wellhead power plants and additionally provides policy guidelines in the execution of geothermal electricity projects either as central or wellhead power plants for grid electricity generation.

Biogas Production and Applications in the Sustainable Energy Transition

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“…(i) Create awareness of biogas power generation opportunities and incentives (ii) Mitigate against high investment costs through tax incentives and access to cheap and readily available finance (iii) Develop local capacity in power plant project design, construction, operation, and maintenance (iv) Through the promotion of decentralized generation, small-scale biogas producers should be allowed to operate as prosumers who sell and consume electricity based on circumstances. This can be realized through the extension of smart grids to rural areas and attractive feed-in tariffs [28,119,171]…”

Numerical study of pressure drops and flow characteristic in high temperature air-water stratified flow using the AIAD model

“…This number is divided into 13 power plants and 11 Geothermal Working Areas [1]. The rise of the issue of gas emissions and climate change trigger geothermal energy more and more in demand [2] [3]. Geothermal power plant consists of two main systems, which is laid below and above the surface.…”

Optimum Bio-digester Design and Operations

“…The gas has a significant role to play in the global energy transition because of the need to transform the global electricity systems from fossil fuel-based generation to low carbon and renewable energy-based power generation. With huge biomass to biogas conversion potential and many feasible biogases to electricity conversion technologies, biogas will play an extremely important role in the energy transition as a renewable energy fuel resource and feedstock for industrial production of chemical fuels and renewable products (Kabeyi, 2019b;Moses Jeremiah Barasa Kabeyi & Oludolapo Akanni Olanrewaju, 2022b;Kabeyi & Oludolapo, 2021aMachado et al, 2021). Microbiallycontrolled generation of biogas is a significant part of the global carbon cycle where we have a natural anaerobic biodegradation estimated to generate 590-800 million tons of methane into the global atmosphere (Bond & Templeton 2011).…”