Metal hydrides for concentrated solar thermal energy storage

17 May 2016 - 11:00am to 12:00pm
320A, Chemical Sciences Building (map ref: F10)

Abstract

Metal hydrides for concentrated solar thermal energy storageCurrently, the population of the world is increasing by 80 million people per year, which, along with technological growth, puts a tremendous strain on global energy production. Even if fossil fuel reserves were not dwindling, alternative energy sources are unquestionably required and many renewable energy projects are underway globally. Some of the largest projects involve the construction of concentrated solar-thermal power (CSP) stations, which harvest the sun’s energy in the form of heat that is used directly to produce electricity [1]. In order to produce electricity at times of low sunlight, thermal energy storage has been implemented at a number of these stations including a state-of-the-art 110 MW plant in Nevada called the Crescent Dunes Solar Energy Plant [1]. Using molten NaNO3/KNO3salts, this station has the capacity to store 10 h of thermal energy for electricity production.

Molten salts are the first generation of thermal energy storage materials used for CSP and, as such have their drawbacks including low heat storage capacity, large volumes, high costs, and an operating temperature that is limited to 565 °C [2]. Metal hydrides have been determined to be 5–30 times more energy-dense than molten salts and have the potential to reduce the heat storage costs of next generation CSP [3,4]. Recent discussion of this topic has identified a range of high temperature metal hydrides that have the potential to operate at temperatures far exceeding those of molten salts (~565 °C), supercritical-CO2 (650 °C), and also the next generation of power tower technology (650 - 800 °C), although reversibility and cost are the key issues to solve [5,6].

I will discuss the recent developments of high temperature metal hydrides and their potential towards integration into main stream power supply.

[1]          M. Fellet, C. E. Buckley, M. Paskevicius, and D. A. Sheppard, MRS Bulletin 38, 1012 (2013).

[2]          D. A. Sheppard, T. D. Humphries, and C. E. Buckley, Mater. Today 18, 414 (2015).

[3]          D. N. Harries, M. Paskevicius, D. A. Sheppard, T. Price, and C. E. Buckley, Proc. IEEE 100, 539 (2012).

[4]          E. S. Freeman, J. Phys. Chem. 60, 1487 (1956).

[5]          D. A. Sheppard, T. D. Humphries, and C. E. Buckley, Appl. Phys. A 122, 406 (2016).

[6]          D. A. Sheppard et al., Appl. Phys. A 122, 395 (2016).

About Terry Humphries

Terry Humphries is currently a Research Fellow at Curtin University, Australia. He was awarded his Ph.D in Chemistry from the University of New Brunswick, Canada, in 2011, where he studied the synthesis and characterisation of Aluminium Hydride. Since, Terry has studied a range of Complex metal hydrides for various hydrogen storage applications at institutes including the Institute of Energy Technology, Norway; WPI-AIMR, Tohoku University, Japan; University of Hawaii, USA and Aarhus University, Denmark. Terry excels in the synthesis of novel air/moisture sensitive compounds and the subsequent characterisation using a variety of analytical methods including X-ray and neutron diffraction, multi-nuclear NMR and vibrational spectroscopy.