Find out how our planet’s thermal energy storage system functions.
The use of renewable energy in homes has advanced significantly thanks to technology. And a key component of this is energy storage. It implies that we can capture renewable energy whenever it becomes available and store it until we need it. For those of you eager to begin building the sustainable home of your dreams, energy storage is perfect!
What is Thermal Energy Storage?
Heating or cooling a medium allows for the storage of thermal energy for later use. In its most basic form, this might entail using a tank of water as a heat storage device, where the water is heated during times when there is a lot of energy and the energy is then stored in the water for use during times when there is less energy available.
To balance energy use during the day and night, thermal energy storage can also be used. Water or ice-slush storage tanks, earth or bedrock accessed by boreholes, and sizable water bodies buried far below ground are examples of storage solutions.
Types of Thermal Energy Storage
Thermal energy storage can be accomplished using a variety of technologies, and depending on the technology used, thermal energy storage systems can store extra thermal energy for a few hours, a few days, or even a few months.
Thermal energy systems are divided into three types:
- Sensible thermal energy storage is considered to be the most viable option to reduce energy consumption and reduce CO2 emissions. They store and release heat energy in rocks or in water. Residential buildings are the best candidates for this type of thermal energy storage.
- Latent heat storage systems store energy without the medium changing in temperature but rather depends on the changing state of a medium. There have been developed substances are known as “phase change materials” that can hold latent heat in their mass. These substances are frequently used in building materials and solar applications, where they absorb and store extra building heat.
- Thermochemical heat storage systems, on the other hand, are based on chemical reactions.
Why Do We Need Thermal Energy Storage?
For good reason, renewable energy and increased electrification are at the heart of many nations’ decarbonization strategies: 90% of the emissions reductions we urgently need can be achieved through energy efficiency and electrification based on renewable energy. Another incentive is the declining cost of renewable energy.
In order to ensure the availability of clean energy when the wind isn’t blowing or the sun isn’t producing solar energy, energy storage is becoming more and more necessary as the use of renewable energy increases. Renewable energy, however, fluctuates.
How Thermal Energy Storage Works?
Thermal stores (such as hot water tanks) work by storing heat in the form of hot water – this heat will last for hours.
Similar to a typical hot water tank connected to a gas boiler, thermal stores can get the majority of their heat from a single source. You might not be aware, though, that they can also have multiple heat sources. For instance, a boiler as well as (or in place of) an immersion heater.
You can connect various renewable energy systems, as well as a traditional boiler, to your hot water tanks because immersion heaters operate solely on electricity. By using these, you can guarantee that you always have heat when you need it while reducing the amount of carbon dioxide released into the atmosphere!
Heat batteries use something called ‘latent heat’ to store their energy as heat. This is how it works, and it’s quite technical: a “phase change material” (PCM) is changed from one state to another (from solid to liquid) using heat or electrical energy. This effectively captures energy.
A heat battery loses much less heat when compared to a cylinder because of significantly improved insulation. As a result, PCM heat batteries are able to store more energy in a smaller volume while also losing less heat due to cooling. Though it sounds complicated, this is all good news!
The process is reversed (turning the PCM from a liquid to a solid), which results in a release of heat when you need to get the heat out again.
There are a few additional benefits as well. There is no risk of legionella because heat batteries don’t contain a lot of water (a bacteria that likes to grow in some hot water tanks if they aren’t frequently heated to extremely high temperatures). Additionally, there isn’t a big pool of water sitting there ready to flood your house if you ever have a leak.
Benefits of Thermal Energy Storage
Thermal energy storage can:
- By storing energy when there is low demand and releasing it when there is high demand, peak demand can be reduced and demand levels can be maintained.
- By ensuring energy is used when it is more affordable and adding more renewable energy to the mix, you can lower CO2 emissions and costs.
- The overall energy efficiency of energy systems should be improved.
- Peak shaving systems often use off-peak power to power heat pumps that can generate heat or cold using less expensive electric power and waste heat from industrial sources in order to balance the loads on the energy system. Thermal energy storage is also a key component of these systems.