For many households, after 9pm the cost of electricity more than halves until 5am the next morning.

And after 11pm, all your electrical appliances and car charging will run on 100% imported renewable electricity.

So set the timers and let nature help run your home.

Use it in the green zone

Would you like to spend less AND reduce your carbon emissions?

Use some of your appliances overnight. It’s that simple. 

This is one of the easiest and most effective ways to reduce both, particularly during winter when the power station is used to top-up our electricity demand.

Not everyone realises that 9pm to 5am is an off-peak period when our electricity is cheaper*. And because less people use electricity after 11pm, we don’t need to use the power station to generate electricity.

Want to do more? Push back your timers to between 11pm-5am to use 100% imported renewable energy. Read on to find out how you can save money and help reduce carbon emissions.

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*Cheaper for customers on an Economy 12 low-rate tariff whose evening time band starts on or before 9pm.

What can I do? 

If you don’t need to use it right away, why not set a timer to come on in the Green Zone?

Electric vehicles
Tumble dryer
Washing machine
Hot water system
Phones, devices and rechargable gadgets

Anything with a built-in timer s very straightforward.

Just set a time delay to switch on between 11pm and 5am, then you can switch off knowing you’re saving money and helping the planet by using 100% renewable energy.

Check the appliance’s make and model online to see how you can save money and carbon by using a time delay.

Don’t have a built-in timer? Why not set a reminder on your phone to switch your washing machine, dishwasher, etc on at 9pm before you head off to bed.

It won’t be 100% renewable until around 11pm, but it’ll be cheaper* and cleaner than earlier in the day.

Worried about running appliances overnight? Manufacturers are unlikely to produce appliances with time-delay functions without having confidence that they’re safe to use. However it’s best to follow approved health and safety advice for running your appliances. This includes having your electrical appliances PAT tested, having tested smoke alarms, and ensuring plug sockets are not overloaded.

Don’t have a built-in timer?

Keen to use renewables but don’t have in-built timers in your appliances? Why not consider a smart plug or plug-in timer. And please check the important note below.

Smart Plugs

Smart plugs make it easy to control the flow of power to any appliance plugged into it.

A scheduling function on these plugs means you can create down-to-the-minute schedules using your smart phone and other devices. This means you can control when you use some electrical appliances and set them to run during cheaper, cleaner times.

How to set up a smart plug power schedule >

Plug-in timers

Mechanical or digital plug-in timers are an inexpensive way run your appliances when you’re not around.

Plug these timers into the wall socket outlet that’s closest to the  appliances you can use. Then just plug in appliances that are below the Watt capacity of your plug and set the time you want it to come on.

IMPORTANT: The Watt rating of your plug needs to be higher than the Watt rating of the appliance you’re planning to use, otherwise it won’t be safe to use. For example, a 3kW tumble dryer cannot be used on a smart plug that is rated at 2kW. And if you are using an extension lead, remember never to overload it.

Check out this handy socket overload calculator

Why does it matter to me?

Over 90% of our electricity needs can be met using 100% renewable energy imported in Guernsey through the subsea cable.

But during busy periods, we all need to rely on fossil fuels to generate the amount of electricity we’re choosing to use during those times. Renewable energy is always imported, but when it’s rush hour on the electricity circuit, diesel generation at the power station is needed to top-up the island’s supply.

We need electricity to work, cook dinner, and light up our homes while we’re awake. But do we need to wash and dry our clothes, clean dishes, and charge electric cars and devices during this time too? For many of us, the simple answer is no.

If we change some of our habits, as a community we have the power to reduce fossil-fuel generated electricity from the power station. And enjoy cheaper, cleaner electricity.

Now that’s electric living.

Driving on sunshine, wind and water

Running your car on 100% renewables

Unlike petrol and diesel, electric vehicles produce no exhaust-pipe emissions and are far cleaner to run. In fact many of our electric vehicles driven in Guernsey produce around 65% less carbon emissions across their entire lifecycle.

Find out more about your vehicle’s carbon impact

In Guernsey, it’s possible to run electric vehicles on 100% imported renewable energy. All you need to do is set your on-board timer to charge your vehicle between 11pm and 5am when Guernsey is powered by imported renewable electricity.

How to set EV timers

Check your car manual or search for how to set the charge timer on your vehicle’s make and model online. To give you an idea, here’s a helpful video for the Nissan Leaf

Find your electric vehicle charger installer

If we all move our usage times, won’t we just push the problem back a few hours?

‘Peak demand’ electricity periods come about because more people need electricity – for example, cooking, lighting, and heating. These peaks will never stop, but when we remove some electricity usage from busy to less busy periods, we will help ‘flatten the curve.’

If we can reduce our demand for electricity during peak times and spread it more evenly across the day and night, we can rely less on burning fossil-fuels at the power station.

The importation cable supplies Guernsey with 60MW (megawatts) of renewable electricity. Any additional usage above this demand and Guernsey Electricity need to start up a generator at the power station. Once our demand exceeds around 70MW, a second generator will need to start up.

At the moment, Guernsey uses roughly 40 MW at 11pm, and even less through the night and early morning. This means it is highly unlikely a new problem will be created if we move some of our electricity usage to off-peak times.

As of January 2022

When are my Economy 12 cheap rate times?

Economy 12 refers to 12 hours within 24 when customers can use cheaper, off-peak electricity. This is made up of 2 hours during the day, and 10 hours during the night.

If you’re unsure of your own time bands, check your electricity meter box to see if it’s been printed on there. They’ll also be shown on the back of your electricity bill.

It’s worth remembering that time bands are assigned to the property, not to the person. If you move house, your off-peak times may be different to what you’re used to so you should always check these.

When are the busy peak times for electricity in Guernsey?

Breakfast, lunch and dinner.

Electricity usage will always follow our behaviour because we need electricity to power much of our lives. Think of it like rush hours. If you’re using electricity more during certain times, it’s likely most of the island are also doing the same.

The biggest peaks are around 8am, 2pm and 6pm.

Each morning most islanders will wake up, switch on lights, turn on heating in winter, have a shower, make breakfast, switch on gadgets, devices and appliances to get ready for the day.

As the majority of people work during the day, electricity will run throughout the day and peak as we prepare or eat lunch. Then the usage will climb sharply again as people head home, switch on lights, turn the heating on, cook dinner and watch TV.

As life generally winds down overnight, our electricity demand also does the same. As less people use electricity then, this is a good time to consider using some of your appliances where possible.

I need to use a lot of electricity during busy peak times such as lunch and dinner. How can I reduce my usage?

Use time delays on appliances

Where possible, switch electricity you do not need to use on demand to overnight time bands – such as running washing machines, dishwashers, electric car charging, etc from 11pm.

Switch off anything you’re not using

Everything you have on is costing you money. Pay for the electricity you need, rather than the excess electricity you use without actually needing to. The money you’ll save can buy you something far more exciting.

And during winter, you’ll also need the power station to power your household during busy periods.

It’s been said many times but it’s worth saying again:

Switch off lights. Take TVs off stand-by. Switch off plug sockets after you’ve finished using them. Each unit you save will save money and not need fossil fuels.


If you heat using electricity, you can reduce your electricity consumption by stopping as much heat as possible from escaping the property. And if you heat with gas or oil, it’s even more important to keep the heat in to avoid generating more greenhouse gas emissions from your property than necessary.

Heating systems only need to replace the amount of heat lost through the fabric of the building, such as walls, windows and roofs. Keep the heat in, and you’ll keep more money in your pocket and help reduce your impact on climate change.

Do some cooking overnight

This isn’t for everyone, but some people use appliances like slow cookers overnight to cook their breakfast, lunch or dinner ready for the next day.

If you can set these to start cooking from 11pm, that takes some of your demand away from busy times when the power station is needed.

Charge up devices overnight

It’s often said it’s best to leave devices such as smart phones and tablets to completely run out of juice before re-charging them again to help maintain the battery’s lifetime.

Either way, these days many of us have several devices which we use during the day so the best time to charge them is overnight when it’s cheaper and less carbon intensive.

Invest in energy-efficient appliances

The less electricity your appliances use, the less you pay to run them. Modern appliances are becoming far more efficient which is great news for saving money and helping the planet.

When the time comes to replace your old washing machine or dishwasher, consider investing in the most efficient model you can afford and reap the benefits of cheaper, cleaner living.

Discover more about your electricity