Latent Heat Thermal storage of latent heat is an alternative to sensible heat system. This system works by taking advantage of the material's ability to store energy through its ability to change phase from solid to liquid or liquid to solid. (Sharma, Tyagi, Chen, & Buddhi, 2009). The process is based on the chemical properties of the chosen material where heat is absorbed or released when the material undergoes a phase change from solid to liquid or vice versa. (Sharma, Tyagi, Chen, & Buddhi, 2009). The process starts when the temperature reaches the required temperature (phase change temperature) and remains constant until the entire process change is completed. Most thermal latent heat storage systems are currently based on the solid-to-liquid transition. The graph below shows the heat buildup for a latent heat system in the case of a solid-liquid change. Figure 1: Heat storage as latent heat for a solid-liquid phase change (Mehling & Cabeza, 2008) The heat storage capacity of a latent heat system for the case of material undergoing solid-liquid phase change can be seen below (Portaspana, 2011):Q= ∫_(T_i)^ (T_m)▒〖m. C_p dT+ m.∝_m.∆h_m+∫_(T_m)^(T_f)▒〖m.C_p.dT〗〗A latent heat system has two main advantages over a sensing system: it allows large amounts of energy to be stored with only small temperature changes thus allow the system to have a high storage density. The phase change process occurs over a long period and allows any temperature change to be adequately controlled. Ice-based technologyIce-based technology, also known as ice storage air conditioning, is the process of using ice to store energy. This method is used to reduce the cost of using energy by transferring energy consumption from above... to the center of the paper... or by turning it back into a high pressure gas. The gas is then used to drive a turbine and generator to produce electricity (Liquid Air Energy Netwrok, 2012). Below is a representation of how cryogenic energy storage works. Figure 4: Representation of cryogenic energy storage system (Highview power storage, 2011) A pilot project is launched in Slough, UK with the aim of producing 300kW using the liquid air cycle. The results obtained were promising, with a process efficiency of 50-60% achieved through recycling the thermal energy produced during the energy recovery process (University of Birmingham, 2013). The system may still lag behind some batteries in terms of efficiency but it has the advantage of having an almost unlimited number of charge and discharge cycles without any loss of storage capacity (Lombardo, 2013).