 
 <prompt> Which one of di following no be measure of energy: kWh, terajoules, or efficiency? Based on di previous question, write a context wey contain di answer. E fit be 1 - 20 sentences. Context: <response>: Phase change materials like paraffin wax and Glauber's salt na anoda thermal storage media. Dis materials dey cheap, easy to find, and fit deliver useful temperatures wey fit use for house (approximately 64 °C or 147 °F). The "Dover House" (for Dover, Massachusetts) na di first to use Glauber's salt heating system, for 1948. Solar energy fit also dey store for high temperatures using molten salts. Salts dey effective as storage medium because dem dey cheap, get high specific heat capacity, and fit deliver heat at temperatures wey fit work with normal power systems. The Solar Two use dis method of energy storage, wey allow am store 1.44 terajoules (400,000 kWh) for im 68 cubic metres storage tank with an annual storage efficiency of about 99%. 