Smart home: Battery storage

What is battery storage?

As the name suggests battery storage is a way of storing electrical energy in a battery or series of batteries. Electrical batteries help you make the most of renewable electricity from solar photovoltaic (pv), a wind turbine, or a hydro-electric system.

For example, electricity generated during the day by solar pv modules could be stored in an electrical battery to use for boiling a kettle or watching the tv in the evenings when your solar pv modules are no longer generating electricity.

Do I have to have solar pv to have batteries?

No, you do not have to have solar pv in order to take advantage of battery storage as the batteries can noy only store the electrical energy generated by your home renewable technology, but a battery can also be used to store electricity straight from the grid at cheap times of the day or night.

This can dramatically reduce your reliance on expensive electricity during peak periods. Most electrical storage systems offer smart management, allowing you to track your energy usage online or within an app.

How efficient is battery storage?

Battery storage is typically around 80% to more than 90% efficient for newer lithium devices, battery storage systems connected to large solid state convertors have been used to stabilise power distribution networks.

What are the benefits of battery storage?

Battery storage systems allow for better use of renewable energy.

The use of batteries to store this energy is a necessity, ensuring the power can be used whenever you need it and not just feeding it back to the grid effectively being wasted.

Making you less dependant on the grid, and minimising electricity bills.

What is battery storage capacity?

Battery storage capacity refers to the total amount of energy your battery can store, but your battery/batteries can not generally totally discharge without damaging them, so systems will have a depth of discharge (DoD) limit, this typically ranges from 80% – 95%, meaning there is a lower usable capacity than the quoted storage capacity.

DC and AC battery storage systems

Solar panels and batteries both provide direct current (DC), and require a device called an invertor to change that to alternating current (AC), which is the electrical energy your house hold uses.

You can connect your battery to the DC side of your invertor or the AC side, lets have a look at both
To connect to the DC side your invertor must have the charging function built in, it will probably be described as a “hybrid” invertor, and you will end up with what is called a “DC coupled battery”, the battery will be positioned before the renewable generation meter, which means that it must not be charged from the AC grid (even if the invertor may be capable of doing so).

If your existing invertor does not have this feature you may be better off installing another invertor/charger that is connected to the AC supply, giving you what is called an “AC coupled Battery”, in this case you will be able to charge your battery from the grid and use cheap off-peak electricity to charge it.

What size battery should I get?

The battery size will depend on your current energy usage, and the size of any generation technologies you have installed, although you do not need to have generation technologies to take advantage of battery storage as you can charge the batteries at night on a cheaper rate to then use the stored energy during the day when electricity is at a higher rate.

It is also worth thinking about considering your future electricity usage, if you are intending to purchase an electric vehicle (EV).

If you would like more information, please call us today on 07482 394225