How we calculate your prices

We'll review your prices several times a year by checking them against other suppliers (using the Energy Retail Price Index) and adjusting them. This means your prices could go up or down, but never above the rates we quote you.

If you'd like you can check the market prices at any time if you'd like to see how we're comparing your rates, and contact us if you'd like more detail about the figures we've used.

What it all means

Calculating energy prices isn't easy, but we want to be open and honest about how we put together the Cap and Track 1 Year tariff prices.

To help you, we've used the these terms in bold below.

  • E7 electricity use (day) - the Ofgem average electricity use during the day in kWh on an Economy 7 tariff
  • E7 electricity use (night) - the Ofgem average electricity use during the cheaper night-time hours in kWh on an Economy 7 tariff
  • Unrestricted electricity use - the Ofgem average electricity use at any time in kWh on a single-rate tariff
  • Gas use - the Ofgem average gas use in kWh
  • Annual market index saving - the reduction in pounds (£) a typical customer in your region will get by being on this tariff (you can also find this in your welcome pack)
  • Electricity standing charge - how much you pay every day depending on where you live, no matter how much energy you use
  • Gas standing charge - how much you pay every day depending on where you live, no matter how much energy you use
  • Annual E7 day cost percentage - the percentage of the total annual cost for electricity used in the daytime
  • Annual E7 night cost percentage - the percentage of the total annual cost for electricity used in the night-time
  • Annual electricity cost percentage - the percentage of the total annual cost for electricity use
  • Annual gas cost percentage - the percentage of the total annual cost for gas use
  • Index value - the energy costs for a typical customer in your region compared with other suppliers (we get this from the ERPI)

All prices exclude 5% VAT.

We'll round your unit rate and standing charge to three decimal places. Where we need to round figures up or down, 0.5 and above will be rounded up, and below 0.5 will be rounded down.

 

Dual Fuel

If you get both your gas and electricity from us, and you don't get cheaper rates overnight, this'll be your price calculation.

Here’s how we’ve calculated your annual standing charge:

  • Electricity standing charge x 365 = your total electricity standing charge in pence
  • / 100 to get your total electricity standing charge in £
  • Gas standing charge x 365 = your total gas standing charge in pence
  • / 100 to get your total gas standing charge in £

Here’s how we’ve calculated the split between your electricity and gas cost. We’ve used a split of 53% of the annual cost for electricity use and 47% for gas:

  • Index valueannual market index saving = our price
  • Our price x the annual electricity cost percentage = our electricity price
  • Our price x the annual gas cost percentage = our gas price

Here’s how we’ve calculated your electricity unit rate:

  • Our electricity price – your total electricity standing charge = total electricity unit cost
  • Total electricity unit cost / unrestricted electricity use = your electricity unit rate in £
  • x 100 to get your electricity unit rate in pence

Here’s how we’ve calculated your gas unit rate:

  • Our gas price – your total gas standing charge = your total gas unit cost
  • Your total gas unit cost / gas use = your gas unit rate in £
  • x 100 to get your gas unit rate in pence

Dual Fuel with Economy 7

If you get both your gas and electricity from us, and you pay cheaper prices during the night, this'll be your price calculation.

Here’s how we’ve calculated your annual standing charge:

  • Electricity standing charge x 365 = your total electricity standing charge in pence
  • / 100 to get your total electricity standing charge in £
  • Gas standing charge x 365 = your total gas standing charge in pence
  • / 100 to get your total gas standing charge in £

Here’s how we’ve calculated the split between your electricity and gas cost. We’ve used a split of 42% of the annual cost for daytime electricity use, 16% for night and 42% for gas:

  • Index valueannual market index saving = our price
  • Our price x the annual E7 day cost percentage = our electricity day price
  • Our price x the annual E7 night cost percentage = our electricity night price
  • Our price x the annual gas cost percentage = our gas price

Here’s how we’ve calculated your electricity day unit rate:

  • Our electricity day price – your total electricity standing charge / 2 = total electricity night unit cost
  • Total electricity night unit cost / E7 electricity use (night) = your night unit rate in £
  • x 100 to get your electricity night unit rate in pence

Here’s how we’ve calculated your gas unit rate:

  • Our gas price – your total gas standing charge = your total gas unit cost
  • Your total gas unit cost / gas use = your gas unit rate in £
  • x 100 to get your gas unit rate in pence