Economy 7 tariffs give you cheaper rates during the night, and more expensive rates during the day. The cheaper rate period is usually seven hours, and with an Economy 10 tariff this goes up to 10 hours. This type of tariff is known as ‘time of use’. If you’re on Economy 7 or 10, you might be able to get a smart meter as some suppliers are starting to offer ones that are able to juggle two tariffs – this could be especially useful as you’ll be able to see which tariff you’re currently using, and how much energy you’ve consumed under each. However, this may not be available for all Economy 7 and 10 providers, so you should talk to your energy company and get all the details before accepting a smart meter.