How much does it cost to run? Appliance calculator at the October price cap

Worked examples at 26.32p/kWh

Every figure below is what the calculator gives at the same settings. Standing charge excluded.

• 2kW heater, 4 hours, 60% duty: £1.26 per evening.
  2000W x 4h x 0.6 / 1000 = 4.8kWh; 4.8 x 26.32p = 126.3p = £1.26
  Run at nameplate the whole time (no thermostat) it is £2.11: 8kWh x 26.32p = 210.6p.
• 1.5kW heater, 3 hours continuous: £1.18.
  1500W x 3h x 1.0 / 1000 = 4.5kWh; 4.5 x 26.32p = 118.4p = £1.18
• 60W electric blanket, 8 hours, 70% duty: 9p per night, £13.27 over 150 nights.
  60W x 8h x 0.7 / 1000 = 0.336kWh; 0.336 x 26.32p = 8.84p a night; x 150 = 1,326.5p = £13.27
• 245W dehumidifier, 8 hours, 70% duty: 36p per day, £32.50 over 90 days.
  245W x 8h x 0.7 / 1000 = 1.372kWh; 1.372 x 26.32p = 36.11p a day; x 90 = 3,250.0p = £32.50

How the number is calculated

kWh = (W x hours x duty) / 1000
£ = kWh x 0.2632
Standing charge not included.
Regional rates vary; paste your bill unit rate to override.
VAT on electricity is 0% this cap period. Do not add 5%.

Duty cycle is the share of “on” time the appliance actually draws its rated watts. A heater’s thermostat, a blanket’s controller and a dehumidifier’s humidistat all switch the element or compressor off once the target is reached. Our defaults (heaters 60%, blankets 70%, dehumidifiers 70%) are assumptions, not measurements. A plug-in energy meter gives you the real figure; enter it under “Measured watts”.

Cost per use is rounded only at the end: pence below £1, pounds to two decimal places at £1 and above.

Questions

How much does a 2000W heater cost per hour at the October cap?

52.6p an hour at full power, at 26.32p/kWh (1 October to 31 December 2026). A 2000W heater uses 2kWh in an hour, and 2 x 26.32p is 52.64p. With a thermostat holding the room and the heater drawing power 60% of the time, the average is 31.6p an hour.

Does an electric blanket cost less than a heater?

Yes: a 60W blanket costs 1.6p an hour at full power against 52.6p for a 2kW heater, both at 26.32p/kWh. Over an 8-hour night at our default duty cycles that is 9p for the blanket and £2.53 for the heater. The blanket warms the bed, not the room, so it replaces the heater only when you are in bed.

How much does it cost to run a dehumidifier overnight?

36p for 8 hours for a 245W dehumidifier at 26.32p/kWh, if the compressor runs 70% of the time. Run flat out for the full 8 hours it is 52p. A machine in a cold room works harder for each litre it collects, so the per-night figure is only half the story.

Is the standing charge included?

No. The GB-average electricity standing charge is 54.83p a day (£200.13 a year) at the October 2026 cap, and you pay it whether the appliance is on or off, so it is left out of every cost-per-use figure here.

What rate should I use if I’m on a fix, Economy 7 or prepay?

Use the unit rate printed on your bill or in your supplier’s app, and type it into the unit rate box. On a fix, that is your fixed p/kWh. On Economy 7, tick the Economy 7 box, enter your night rate and the hours that fall in your night window. Prepayment meters have their own cap rates, so use the figure on your statement. The 0% VAT on electricity applies to fixed and prepayment tariffs too.

When does this cap period end?

31 December 2026. The 26.32p/kWh rate covers 1 October to 31 December 2026; Ofgem sets a new cap for 1 January to 31 March 2027 and we will update the default rate when it does. The 0% VAT on household electricity is funded to 31 March 2027.

Guides behind these numbers

• Best electric heaters UK, ranked by cost per hour
• Best electric blankets UK, with cost per hour by wattage
• Best dehumidifiers UK, ranked by what a night costs to run
• Cost to run a fan, air con unit or dehumidifier
• Heated airer running costs
• UK running cost index: every common appliance at the cap
• Heating cost index: gas boiler vs heat pump vs direct electric
• October 2026 energy price cap explained
• Electricity VAT cut 2026: what it saves and when it ends