HELEC brings more than seventeen years’ experience supplying energy solutions to embrace and harness the very best in reducing carbon emissions, enhancing renewable technology and improving energy efficiency. The company has an extensive range of space heating and hot water systems suited to both domestic and commercial use – and can even design and develop a bespoke system to ensure reduced costs and greater environmental protection. In this blog, we’ll take a quick look at the history of energy efficient storage systems, sometimes better known as thermal stores.

What is thermal energy storage?

The technology behind a thermal energy store can vary wildly, but the end goal is the same – allowing excess energy to be stored safely and reserved for use at a later time. This might be hours, days or even months in the future, with the timescale varying dramatically depending on the purpose of the store and the building in which it is fitted. This tech is considered particularly useful for helping to cost-effectively balance the need for Combined Heat & Power systems, renewable Solar energy and conventional heating systems to work in harmony.

Calculating the optimal volume size of a thermal store against the specific technology being considered is essential to ensure the most effective and efficient results are achieved. If too small a store is sized then it will reach its thermal capacity too soon and cause the energy producer to shut down prematurely, or worse overheat and cause issues.

Thermal stores are generally highly insulated water tanks, which can store heat for long periods of time. They have evolved over time to suit a number of different systems, including most pertinently:

  • Solar Thermal Water Heaters

Drawing thermal heat from the solar panels, this system can heat rooms via space emitters (radiators/underfloor htg)as well as domestic hot water. It is usually designed to prioritise a solar thermal heating system to preheat domestic hot water above other sources of heat requirements due to the UK seasonal restrictions for potential solar gain being the best in the summer months.

  • Combined Heat & Power (CHP) Stores

CHP units generate thermal and electrical energy from a single fuel source making them an excellent cogenerating application.
The thermal heat in the CHP engine and alternators water jacket is transferred away from the engine casing passing through a plate heat exchanger which absorbs the heat and pumps it into a connected thermal store. The heat exchanger then returns a cooler liquid back into the CHP engine circuit and the process is repeated continuously.
The hot water “flow” from the CHP is connected to the top of the store which encourages thermal stratification working from the top down ensuring the return temperature is as cold a temp as possible so the hydraulic system gets the best chance to work for as long as possible when a reduced thermal load is being used.
By using a sized thermal store with a CHP it provides a thermal stabiliser enabling the unit to operate in a regular manner thus reducing the number of stoppages

  • Wood-Fuelled Heating (Biomass)

Solid fuel wood chip and log Biomass boilers are considered to be the best renewable source of energy generation as it uses a fuel source that absorbs CO2 when a wood source is growing, then emits CO2 when burnt but can be replaced with new growth relatively quickly (compared to coal).
Biomass heating systems can generate large volumes of hot water which can be stored to provide a speedier domestic hot water-heating time when needed.

  • Solar Thermal Domestic Hot Water Heating Systems

A solar thermal system works by transferring the heated thermal liquid within the solar thermal panels on the roof arrays down into a coil within a solar rated thermal store which holds potable water (water for human consumption, bathing & washing)

This means domestic hot water is then ready for use as and when.