John Gilham, Group Technical Director at Green Building Renewables, has compiled a beginner’s guide to solar power and battery storage:

*How do solar batteries work? Solar batteries are designed to capture the surplus solar energy usually exported to the grid, storing it for use later and allowing you to save money from buying electricity when the sun isn’t shining. They can be easily added to an existing solar panel system with minimal disruption.

Solar batteries convert the DC energy produced by solar panels and store it as AC power for later use. When you install a solar battery as part of a solar panel system, you can store excess electricity generated by them at your home instead of having to send it back to the grid.

During the day, the solar panel system generates solar electricity. The battery storage system will check if all the generation is being used to power your lights and appliances.

If you are not using all the electricity, surplus energy is used to charge the battery and once the battery is fully charged, if there is still more solar electricity being generated, this will be exported to the grid.

In the evening or at times of low solar generation, solar panels have reduced output. If your demand exceeds the electricity generated from your solar panels, it can be diverted from your battery. This ensures that you are entirely using the solar power you have captured.

*What are the benefits of solar battery storage? Solar battery storage has several key benefits. You save more money on your energy bills by using stored solar energy in the evenings or when the sun isn’t shining and you won’t need to draw as much energy from your supplier, saving you even more money on your bills. You are also less dependence on the national grid as solar battery storage means you can still power your home or business during a power cut. You will also be less affected by price hikes as using your self-generated solar energy; you will be drawing less from your supplier. Y

*What is the lifespan of a solar battery? Solar batteries have an approximate lifespan of 10-15 years, depending on the manufacturer. Once they need replacing, a new one can easily be swapped into a solar panel system with minimum fuss.

*Can solar batteries be used to power other appliances like cars? Yes, the stored energy in a battery can provide electricity to a whole range of appliances, including electric vehicles.

How big a solar battery system can I install on my house? This depends on the size of the solar PV system and the number of solar panels you install; however, with a battery like the Tesla Powerwall, which is a 13.5kwh AC coupled system, you can stack up to six of these together. The Fox ESS battery is a 2.6kwh battery, and you can install up to seven batteries on a domestic property, meaning you can have up to 18.2KWH of storage in your home.

*What is the Smart Export Guarantee? During really sunny weather, a solar panel system can generate excess energy that exceeds your battery storage. When this happens, the system owner can sell the extra energy back to the grid under the Smart Export Guarantee. You must sign up for a company’s SEG tariff.

Battery storage systems cost an average of £2,000. Visit York based www.greenbuildingrenewables.co.uk for more details

A beginners guide to solar power and battery storage