Maintaining a steady supply of things like food, water and energy is essential for our survival. We preserve food and water for storage and keep reserves of fuel for the winter. But as we migrate to using clean energy it gets more difficult. Solar, wind and tidal energy sources are intermittent; we need some way of storing the energy we harvest from renewables, so that it is available when we need it.
We use batteries to store electricity for when we need it and battery technology has advanced tremendously in recent years. We routinely store energy in the form of hot water in our houses, but we are only just starting to do the same with electricity. Products such as the Tesla Powerwall provide an opportunity to store electricity from solar panels, so that it can be used at home rather than being exported to the grid. All of which is great, for people who live in sunny places, have solar panels and some extra cash (the Powerwall currently costs about £8k.) But do domestic batteries have a market beyond those people with their own PV and some spare cash? I think that the answer to that question is a resounding ‘yes’ for several reasons.
Most houses in the UK will have a Smart Meter by 2020 and it won’t be much longer before we have ‘Smart Tariffs’ widely available, which will offer cheaper electricity at times of low demand, with higher prices during peak demand periods. Combine a Smart Tariff with a domestic battery and we have a way of buying electricity cheaply and storing it until its needed. Add the potential use of smart controls and we have new opportunities to control electrical our appliances, so that they avoid the expensive periods and talk to the home battery, to optimise energy use and storage. The battery also acts as a back-up, so that computers, routers and smart devices stay on if there is a short power blip, as can often happen.
Reusing electric vehicle batteries in this way is becoming more common, such as in the Nissan XStorage Volvo are also experimenting with used electric bus batteries in Sweden. With more electric vehicles on the road, these ‘second life’ batteries are already driving down the cost of domestic batteries. Extending the life of vehicle batteries also reduces their environmental impact. Widespread uptake of home batteries can potentially lower the strain on the electricity grid and make renewable energy more cost effective and less reliant on fossil fuels to provide power when wind and PV aren’t available.
Homes with battery storage also have potential benefits when considering electric vehicle charging. If a vehicle needs charging during a peak tariff period, the domestic battery can provide the charge if it is correctly engineered. So, the owner doesn’t have to risk paying to recharge their vehicle at an expensive time of day.
Scale all of this technology up for commercial and public buildings and the potential benefits are huge.