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Energy Today
Published in Anco S. Blazev, Global Energy Market Trends, 2021
The major practical division is that between primary and secondary energy sources, as follow: Primary energy sources, which include coal, oil, natural gas, solar, wind, water falls, tidal, biomass and geothermal. These are called primary because they are found in nature and can be used one or another way to generate power (heat and/or electricity).Secondary energy sources, which include electricity and hydrogen, since these are not found in nature, but instead are obtained by a conversion of the primary energy sources. I.e., burning coal to generate electricity, or using solar energy to decompose water for hydrogen production. Refined fuels, such as gasoline and diesel are also secondary sources, because they are obtained by processing a primary fuel, crude oil.
Complexity and Communication
Published in Susan Krumdieck, Transition Engineering, 2019
We normally think of energy as flowing through the energy system, from extraction to conversion, distribution and end-use consumption. Figure 3.1 is a schematic representation of energy conversions, from the primary form found in nature to useful energy services. Primary energy has no commercial value. The primary energy can be in the form of renewable sources, for example, flowing water, geothermal heat, wind, solar insolation and plant biomass. Primary energy is also in the form of finite resources, for example, fossil carbon and uranium. Extraction requires a certain amount of consumer energy for drilling, mining, pumping and building mines or dams. Refining is needed to make different kinds of fuels from extracted crude oil or uranium. Power generation from fuels requires a power plant and cooling water and also produces waste heat. More energy is consumed in moving fuels to customers, and electricity is lost in transmission. These costs are usually included in the conversion of primary energy to energy products. Energy products have commercial value and are purchased by customers by volume or weight of fuel, or kWh of electricity. The energy products do not provide services in themselves. Another conversion process in an engine or appliance is needed to provide the useful energy service. This conversion also produces waste heat. Most of the end-use energy is also waste heat. In particular, older types of lighting, electronics and vehicles have very low conversion efficiency.
UK Energy Sector: Past, Present and Future
Published in S. C. Littlechild, K. G. Vaidya, Energy Strategies for the UK, 2019
S. C. Littlechild, K. G. Vaidya
In discussing energy, it is conventional to draw a distinction between primary and secondary energy or fuels. Primary energy refers to the form in which energy is recovered directly from nature. For Britain, the main sources of primary energy are coal, oil, natural gas and uranium. By convention, electricity generated by nuclear power plants, which use uranium as their fuel, is referred to as a primary fuel. Other sources of primary energy are more important in other countries and yet other sources may become more important in the future. They include water flowing over a dam (generating hydroelectricity), wind, waves and the sun.
Condition-based monitoring as a robust strategy towards sustainable and resilient multi-energy infrastructure systems
Published in Sustainable and Resilient Infrastructure, 2023
Nita Yodo, Tanzina Afrin, Om Prakash Yadav, Di Wu, Ying Huang
Energy infrastructures system plays a vital role as a backbone to other critical infrastructures (CIs) such as the transportation system sector, communication sector, defense industrial base sector, emergency services sector, or financial service sector (Praminta et al., 2020). The common energy sources used in the United States can be categorized as primary and secondary. Primary energy sources include non-renewable (petroleum, natural gas, coal, and nuclear) and renewable (solar, wind, hydro, geothermal, and biomass) energy. Secondary energy sources, for example, electricity and heat, cannot be mined or harvested, instead they are produced or converted from primary energy sources. Based on the April 2022 monthly energy review data source from the U.S. Energy Information Administration (EIA), the amount of energy consumed by U.S. consumers from different energy sources in 2021, with petroleum and natural gas alone making up about 68% of the overall energy consumption and renewable energy only accounting for 12% (U.S. Energy Information Administration, 2022). The 2021 EIA data also hinted that 96% of the secondary energy source, utility-scale electric power generation, is sold to other sectors such as transportation, iAndustrial, commercial, and residential.
Evaluation of wind energy potential: a case study
Published in Energy Sources, Part A: Recovery, Utilization, and Environmental Effects, 2022
Bekir Adem Çakmakçı, Engin Hüner
Mainly carbon (fossil) based fuels such as coal, oil, natural gas, and wood, also known as nonrenewable energy resources, are utilized to meet the world’s energy needs (Omer 2008). The use of fossil fuels as the primary energy source has an essential role in the accumulation of greenhouse gases in the atmosphere. It causes adverse environmental effects, such as global warming (Bilgen 2014). Thus, it shows the importance of the conscious use of energy resources in the countries. The energy deficit caused by the failure to meet the energy demand with the existing resources necessitated the countries to revise their current energy programs and further study alternative energy sources. Renewable energy sources have been gained significant importance worldwide because of desirable features such as free from the disadvantages of fossil fuels, sustainability, and not causing environmental problems (Wiser et al. 2016). Thus, an excellent opportunity has been emerged for countries to meet energy demands from domestic sources. The wind is a renewable energy resource with continuous and inexhaustible form properties, formed as a result of the natural atmospheric transformation process. Wind energy has a cost-effective and local economic development activity (Abbasi and Abbasi 2016; Saidur et al. 2011).
Effect of gas pressure and clamping pressure on interfacial contact resistance of a cylindrical polymer electrolyte membrane fuel cell
Published in International Journal of Sustainable Engineering, 2021
Amit C. Bhosale, S. R. Suseendiran, Kiran Rokhade, Raghunathan Rengaswamy
Alternatives to primary energy sources have been pursued since mid-nineties in response to the global warming and rapid depletion of fossil fuels. Hydrogen, due to its high energy density and pollution free nature, is being realised as a replacement for conventional fuels by employing in devices such as polymer electrolyte membrane fuel cells (PEMFCs) to produce electricity (Wang et al. 2020). PEMFCs have been considered for applications such as automobile, stationary, space etc. (Gao et al. 2016; Markgraf et al. 2012; van Biert et al. 2016; Yilanci, Dincer, and Ozturk 2009) due to their high power density and low startup time. Cylindrical PEMFC, inspired from solid oxide fuel cells, is considered as a better alternative than the conventional planar PEMFC. The structure holds the membrane electrode assembly (MEA) firmly between a set of two concentric cylinders. The absence of conventional bipolar plates (BPPs) and end plates in cylindrical cells when compared to the planar architecture can be harnessed to increase volumetric and gravimetric power densities (Bullecks et al. 2010; Mahata et al. 2012; Othman et al. 2016).