What savings can you make with an heures creuses electricity contract?

Reader Question: I have an off-peak electricity contract but a friend said it only really saves a few centimes off the bill. Is this true?

Electricity contracts based on peak and off-peak (heures pleines and heures creuses) see cheaper prices during the latter (typically eight hours during the evening), in return for higher ‘peak’ prices.

They are used by grid operators and suppliers to spread electricity demand through the day.

Savings will vary between households, however general estimates are available. 

Engie provides the example of a family of four, in the Ile-de-France in a 120m² property, which is fully electric (including water boiler, heating, etc).

If they subscribe to a standard tariff, their bill would be €2,941.34 for the year. 

Subscribing to an off-peak contract would see higher bills if consumption was not geared towards off-peak hours, as base prices during heures pleines are higher than normal. 

For example, if the family signed up to an off-peak tariff but only consumed 10% of their energy in off-peak hours (and 90% at peak times) they would pay €3,109.66 annually. 

In this example, parity is met when 38% of the energy consumed is during off-peak hours. Above this, savings begin to be made and the family’s bill would, for example, be €2,743.48 if 70% of usage is heures creuses (saving €197.86).

For its part, electricity company EDF estimates that more than 33% of energy needs to be consumed in off-peak hours to make savings.

Savings depend on your habits 

Taking this as a base, if you use around 40% of your energy consumption in off-peak hours, you will save money. 

If you can do this – for example by using smart apps and plugs to have the most energy-guzzling devices come on during off-peak hours, ensuring your boiler is set to heat at this time, etc – it could be beneficial and the more you gear consumption towards off-peak hours, the more you save.

However, if you are unable to do this it could even end up being more expensive. 

Incoming changes to off-peak hours, seeing them split between evenings and afternoons, may make it easier – or in some cases more difficult – for you to reach profitability, depending on your habits, so check what is planned by your provider.

Another option is considering a contract using the ‘jour rouge’ system which sees cheaper energy costs on most days in exchange for certain winter days seeing high costs. In this scenario, you need to ensure you manage consumption on ‘red days’ to minimise high bills.