Are sand batteries the future?
One of the challenges for scaling green energy is the lack of cheap and reliable ways in which to store solar and wind energy when the wind doesn’t blow or the sun doesn’t show.
As useful as Lithium-Ion batteries are for things such as electric vehicles, these batteries need scarce materials and are too expensive to easily scale.
So what if a ubiquitous material like sand could be used to partially solve the battery dilemma that hampers our fight against climate change?
In this short article, we introduce you to sand batteries, where and how they are being developed and how they may help your business drastically reduce its energy bills.
Contents
- What is a sand battery?
- How does a sand battery work?
- Why is sand a good material for batteries?
- How about using water instead of sand?
- Are there sand batteries in the UK?
- Can sand batteries help fight climate change?
- Can you make your own DIY sand battery?
- Can sand batteries help my business save energy?
- This is interesting, but how can I save on my energy bills today?
What is a sand battery?
The concept of a battery is normally seen as storage for electricity, but may actually also be used as storage of energy in other forms, such as heat.
A sand battery is a type of thermal battery that uses the favourable thermal properties of sand to store energy as heat for long periods of time.
This heat energy can then be used for any heating applications, such as keeping buildings warm during winter.
How does a sand battery work?
The prototype of a commercial sand battery currently being trialled in Finland startup Polar Night Energy uses a silo-like structure to hold 100 metric tonnes of sand.
Some of the electricity produced from renewables nearby is used to heat the sand to an optimum temperature of 500C, which it can hold even during harsh polar winter months.
Water can be heated using the hot sand and then transported via pipes to local buildings, swimming pools and any infrastructure that needs heating, replacing the need for gas-powered heating.
Why is sand a good material for batteries?
There are many reasons that sand has been used as means of thermal storage for thousands of years.
Firstly, sand can be found virtually in all corners of the world as it is essentially eroded quartz minerals which happen to be the most common mineral on Earth.
Secondly, sand has a very high melting point of around 1700C, allowing virtually an infinite amount of heat to be stored without changing any of its properties; these are batteries for life.
Thirdly, sand is a permeable material which means that any water leaking into its container can quickly flow away from it, and prevent the formation of problematic algae or mould.
How about using water instead of sand?
Many cooling and heating applications use water as a heat sink, so many people question the unorthodox use of sand.
However, water is very valuable for other uses and is becoming an increasingly scarce resource. Also, its capacity to store energy is hampered by its low boiling point of 100C.
The fact that water can leak and host problematic algae or moulds that thrive in humid environments means that constant maintenance is required.
Are there sand batteries in the UK?
No, there are no commercial sand batteries built in the UK despite this being a concept that has been explored by researchers since the 1970s energy crisis.
The concept sand batteries being trialled in Finland are the first commercial and scalable prototype that can store plenty of green energy.
Can sand batteries help fight climate change?
According to Ofgem, half of the energy consumed in the UK goes into heating (760 TWh), making it an important sector to decarbonise if the UK is going to meet its 2050 climate targets.
The Finnish prototype is designed to disrupt this sector as it is designed to store green energy as heat and create an alternative that is cleaner and cheaper than gas.
Can you make your own DIY sand battery?
The concept of using sand to store and utilize heat probably pre-dates history, as sand and rock ovens have been used for thousands of years for cooking and heating dwellings.
This is essentially the same as the ‘sand battery’ idea being explored by the Finnish, and there are already many DIYers that have been experimenting and even using the technology in their daily lives.
This DIY blog shows that making your own DIY sand battery is perhaps not as far-fetched of an idea as we might initially believe.
Can sand batteries help my business save energy?
Absolutely, especially if you generate your own green energy. It is only a matter of time until we see a surge in sand battery prototypes for various applications, including some designed to fit in smaller business properties.
This is interesting, but how can I save on my energy bills today?
If you are not up to the task of making your own DIY sand battery for your home and business, you can use our business energy supplier comparison tool which takes advantage of the free market to get you the best deal possible.
Most business owners in the UK haven’t realised they can re-negotiate their contracts or even change suppliers, especially when it comes to switching business water suppliers as this market was more recently deregulated.
In any case, we hope you found this interesting, and we would be delighted to hear of your DIY sand battery/oven experiments!
