High-temperature electrolysis HTE

The project in preparation aims to research and develop high temperature electrolysis (HTE), which could be used in combination with the Generation IV nuclear reactors. Since NRI already has helium and lead loops, there is a plan to use them for demonstration and investigation of high temperature electrolysis. 

The operative temperature could play a crucial role for the development of a very efficient electrolyser plant. Solid oxide cells (scheme c in Fig. 2.4) have been proposed for high temperature electrolysis (HTE), because of the strong resistance at high temperatures of the related electrolytes. With respect to traditional room-temperature electrolysis HTE modules presents two main advantages [87] ... 

In the literature, the acronyms SOEC (Solid Oxide Electrolyzer Cell) or SOE also occur fairly regularly. The term high-temperature electrolysis (HTE) is fairly common, referring to the operating temperature of the component (typically 800°C) rather than to the nature of its electrolyte. 

G-3 Estimated costs for conversion of natural gas to hydrogen in plants of three sizes, current and possible future cases, with and without sequestration of C02, 202 G-4 Estimated effects of the price of natural gas on the cost of hydrogen at plants of three sizes using steam methane reforming, 204 G-5 Power cycle net efficiency (qel) and thermal-to-hydrogen efficiency (qH) for the gas turbine modular helium reactor (He) high-temperature electrolysis of steam (HIES) and the supercritical C02 (S-C02) advanced gas-cooled reactor HTES technologies, 212... 

NOTE LWR = light-water reactor S-AGR = supercritical C02 advanced gas reactor S-I = sulfur-iodine Cu-Cl = copper-chlorine HTGR = high-temperature gas-cooled reactor AHTR = advanced high-temperature reactor HTES = high-temperature electrolysis of steam. 

FIGURE G-6 The energy needs for hydrogen production by the gas turbine modular helium reactor (He cycle) high-temperature electrolysis of steam (HTES) and the supercritical C02 (S-C02 cycle) advanced gas-cooled reactor HTES technologies. NOTE HHV = higher heating value. 

The denominator in this efficiency definition quantifies all of the net thermal energy that is consumed in the process, either directly or indirectly. For a thermochemical process, the majority of the high-temperature heat from the reactor is supplied directly to the process as heat. For HTE, the majority of the high-temperature heat is supplied directly to the power cycle and indirectly to the HTE process as electrical work. Therefore, the summation in the denominator of Eq. (1) includes the direct nuclear process heat as well as the thermal equivalent of any electrically driven components such as pumps, compressors, HTE units, etc. The thermal equivalent of any electrical power consumed in the process is the power divided by the thermal efficiency of the power cycle. For an electrolysis process, the summation in the denominator of Eq. (1) includes the thermal equivalent of the primary electrical energy input to the electrolyser and the secondary contributions from smaller components such as pumps and compressors. In additional, any direct thermal inputs are also included. Direct thermal inputs include any net (not recuperated) heat required to heat the process streams up to the electrolyser operating temperature and any direct heating of the electrolyser itself required for isothermal operation. 

High-temperature steam electrolysis (HTE) High-temperature gas-cooled reactor (HTGR) Yes... 

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