As the National Grid Electricity Systems Operator (ESO) warned of potential, though unlikely, blackouts this winter, it also said that they could be avoided in part by households and businesses helping out when there is not enough electricity around.

The ESO called for people to “save money and back Britain” by reducing their use during peak times in the early evening.

It is expected to launch a voluntary scheme from the start of November which will alert people when savings are needed. The scheme will run until the end of March.

There is still very little detail on how the scheme might work for households, but here we try to answer some of the questions about how to sign up and how much you can save.

Who can sign up?

There is no easy answer to this. It depends on many factors. For instance not all energy suppliers might offer this scheme to their customers, so you will need to be supplied by one of those who do.

It will also depend on what terms your supplier offers the scheme and whether you meet those criteria.

The scheme is also entirely voluntary, so no one will be forced to participate.

How does it work?

If you are able to sign up, your supplier will ask you to reduce your electricity use during certain hours when supply of electricity is low this winter.

For instance you could get a text on a Thursday saying that high demand is expected tomorrow at between 5pm and 7pm.

If you then use less electricity during those hours than you would normally, your supplier will reward you.

You can still use electricity during those hours, and you will not be punished if you use the same amount or even more than usual during that period.

Does it give the grid the right to shut off supply to my home, or turn off my oven or TV?

No. You still have total control over your electricity use.

Why has this system been developed?

There are a lot of benefits to developing a system like this. It can be used to help balance the electricity grid in the future on days when there might be lower wind or solar power available.

But the reason the system is being prepared for this winter is partly to avoid the potential of blackouts during peak-use hours if the supply of gas to power stations dries up.

If demand from households and businesses is higher than the amount that power generators can supply, there might be blackouts. This can help reduce that risk.

How much money can I save?

This is unclear and depends on how your supplier decides to run the programme.

Ovo Energy, which is running its own version says that households could save around £20 each month if they reduce their use during peak hours.

How will the money be paid to me?

This will depend on your supplier. Some might give you vouchers, others might return cash to you, and many will probably just cut the amount from your energy bill.

Do I need a smart meter to sign up?

Many suppliers will probably require a smart meter for you to sign up. The Electricity Systems Operator says that it needs half-hourly data from households to run the scheme.

But if your supplier can figure out a different way to get data on your use every half an hour then you might still be able to sign up.