Thermal energy storage (TES) has been battling a certain amount of scepticism because of doubts concerning the availability of fast and dispatchable energy which a lot of other storage systems can boast about. Despite concerns, TES has been promising because more than 90% of the energy generation is wasted as heat. So, it has been a long quest to harvest this wasted heat and reuse it for energy generation through TES systems, which is pretty smart don’t you think?

It is also helpful to note that TES is not constrained by geographical locations like how pumped hydro systems are. It can also be modulated in size to fit the generation capacity. It also has the flexibility to make use of sustainable materials in its fabrication while also proving to be a relatively safe form of storage, unlike batteries and flywheels that may release energy destructively. TES systems comprise sensible heat storage which means that the temperature changes that a system undergoes are without a phase change. Another TES system is thermochemical heat storage which makes use of a bunch of chemical reactions to store chemical energy with the use of heat. However, in my opinion, the most interesting one is called latent heat storage which comprises the technology known as Phase Change Materials (PCM).