This IS the dawning of the Age of Aquarius.  A technological step-change in innovation in how we generate, distribute and use electricity is underway. The Grid is groaning; distribution network operators are desperately seeking management solutions.  The rapid deployment of solar PV has acted as a catalyst, a disruptor.  A disruptive innovation is an innovation that creates a new market and value network and eventually disrupts an existing market and value network, displacing established market leading firms.  Bye, bye Big Six, bye bye fossil fuels.

Hang on” I hear you say – “the sun only shines in the daytime while I’m at work.  It’s never going to be able to replace conventional fossil fuel generation.

Enter the humble battery. Not exactly new technology but one we take for granted. Batteries are not just to power those fluffy bunnies on TV adverts.

A solar PV system on your roof will generate electricity during the day that you can use in your home. Without a means of storing that solar electricity, any surplus energy that you don’t use will be ‘exported’ to the local electricity grid. During times when the panels are no longer generating (or not generating enough for your needs), you still need to buy electricity from your electricity supplier – unless you have a storage solution!

According the Building Research Establishment this is how it works:

‘Energy storage’ lets you store the surplus solar electricity, instead of exporting it. Battery storage lets you use more of your solar PV system’s output (in the jargon, it increases ‘self-consumption’). This reduces the amount of grid electricity you need to buy, saving you money on your electricity bill.

During the day:

  • the solar PV 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’re not using all the electricity that the solar PV system is generating, then the system will ensure that any surplus energy is used to charge the battery
  • once the battery is fully charged, if there is still more solar electricity being generated, this will be exported to the grid (or in some systems, will be diverted to other uses e.g. to an immersion heater)

In the evening or at time of low solar generation:

  • the solar PV panels have a reduced or zero output
  • the battery system can discharge the stored electricity, providing you with renewable-generated electricity at no additional cost
  • once the battery is discharged, if you need to use more electricity, you buy it from your electricity supplier.

All pretty straightforward, but did you know that you could also use storage to generate a significant income?

It’s certainly true of businesses right now and I have no doubt that domestic users will also be able to reap the benefits of Time of Use tariffs before too long. The initial cost of a battery storage system is perhaps why battery storage hasn’t so far been hugely promoted even to businesses, however prices are beginning to decline and will continue to do so significantly in the future.

So how do they work? Technically, it requires the conversion of electrical energy into chemical potential energy to be stored. When the energy is required for use, this energy will be converted back from chemical potential energy into electrical energy – in other words its stored as chemical potential energy until it’s ready to be used. As well as being cheaper it also means the energy is far more reliable than relying on the National Grid. Battery storage is going to ensure you can achieve more sustainable, secure and affordable energy; and even holds the potential to generate revenue by selling energy back to the National Grid as and when they require it to meet their demands. When used by a business, it means the business can avoid peak power prices; businesses using a high level of energy at peak times may be paying more but by using a battery for power and recharging it either during night-time hours when energy prices are cheaper, or by using renewable solar energy, it will save them money.

Various domestic pilots are underway so it’s only a matter of time before we can look at storage in our homes

So “let the sunshine in” – even at night.