Off-Peak Electricity | Use cleaner, cheaper electricity | Guernsey Electricity

Tariffs changed from 1 July 2025. Click to find out more. 

Save money and carbon

Powering Life in Off-Peak

Use, run and charge electrical appliances between 11pm and 5am to use imported 100% lower-carbon energy. 

Guernsey's electricity load profile

What is 'Peak Demand'?

Peak demand is the time when consumer demand for electricity is at its highest.

This is usually around breakfast, lunch and dinner, and is simply because more people are indoors and using electrical equipment to power their lives.

In Guernsey, we import around 60MW of low-carbon energy from the European grid. But when customers demand more than 60MW of electricity, this must be topped up using diesel generators at the Vale power station. 

Using electricity during these peak times can cause higher greenhouse gas emissions - especially during the colder, darker months - plus increases wear and tear on equipment which costs money to maintain.

Less pressure on the power station = less local air pollution and less costly maintenance and repair.  

An aerial shot of the vale power station

Want some help reducing your reliance on fossil-fuels? Find out more about our services designed to help islanders get energy smart. 

 

Home Energy Audits

Here's an example 

In January 2024, Guernsey reached its highest demand at 94.2MW in response to cold winter weather that week. 

As mentioned in the news, Jon Sexton, Head of Engineering and Design at Guernsey Electricity, said: “The maximum energy we can import through the subsea cable is 60MW, which means that generators at the Vale Power Station were required to meet the additional demand."

This meant we needed fossil-fuels at the power station to meet the extra demand - for ease of reference, the 60MW importation capacity has been marked up below.

It's only natural to use more electricity during colder, darker months - meaning it's even more important to be mindful of the electricity we're using and move what we can to the cleaner, off-peak periods between 11pm and 5am.

 

Peak Demand Guernsey January 2024

How can I use low-carbon electricity? 

Where possible, move as much electricity usage as you can to between 11pm and 5am.

The best appliances to use 'off peak' are those with in-built time delays, such as:

  • Hot water cylinders
  • Washing machines
  • Tumble dryers
  • Dishwashers
  • Electric vehicle charging points
  • Slow cookers 

Don’t have built-in timers?

Hold off on using these appliances around breakfast and dinner until later in the evening. Any time from 9pm works well, provided this is on or before your Super Economy 12 low-rate time band.

Find your specific time bands on the back of your electricity bill 

Find your low-rate timebands

Here’s an example:

A quick 1-hour cycle of a washing machine at 6 or 7pm, especially during winter, means fossil-fuels are needed to generate the power. 

In other words, at peak times you’re using fossil-fuels to clean your clothes 

But if you set a time delay to start between 11pm and 5am, you can get your clothes clean using low-carbon energy, as electricity demand is so low during this overnight period.

Cleaner energy for cleaner clothes. 

Plus, using a longer 'EcoMode' should help save you money too as it actually uses less electricity and less water, especially if you’re on the Super Economy 12 tariff which offers low-rate electricity over 50% cheaper than earlier in the day. Look after those pennies, as over time it all adds up!

Washing machine timer

 

 

How can I spend less money? 

Bad habits cost you money, and when it comes to electricity there are so many ways people can reduce their bills. Why pay for electricity you aren't using? 

First, a few things to check. 

  1. Are you on the Super Economy 12 Tariff? If not, sign up today 
  2. What are your low-rate times? If you're not sure, check the back of your electricity statement
  3. Do your appliances have time delays? If not, try using a smart plug for plug-in appliances
Once you're all set with your low-rate times, simply use your electrical appliances as much as possible when it's over 50% cheaper to use. It's a win-win for your wallet and the planet. 

Or if you'd prefer someone to visit your home and help save energy for you, why not book in a home visit with one of our Energy Savers. 

Home Energy Saving Audit 

 

Book in one of our Energy Savers to help you save energy

Want to stay in the know about our island's electricity?

Sign up for our E-Newsletter