Marcus Bell
Marcus is an electrical engineer who spent most of his career in building services, sizing circuits for housing associations. He builds the calculators on Vukla, sources the wattage figures from manufacturer specification sheets, and keeps the tariff data current.
Articles by Marcus
Heated airer against tumble dryer, which is cheaper to run per load?
A 300W heated airer costs about 32p for a four hour session. A tumble dryer costs about 66p a load. Here is the full arithmetic, and the catch nobody mentions.
EntertainmentDoes leaving a phone charger plugged in cost anything at all?
A charger left in the wall with no phone on it costs about 23p a year at the current price cap. The broadband router next to it costs £23.06 a year, which is where the attention belongs.
EntertainmentHow much does it cost to run a PS5 per hour in the UK?
Sony's own measured figures put a PS5 at 215 watts in game, which is 5.7p an hour at the current price cap. A three hour session costs 17.0p and rest mode costs about £4 a year.
KitchenHow much does a microwave cost to run per hour, and per reheat?
A microwave costs about 34p an hour at the current price cap, but a five minute reheat is only 2.9p. The catch is that the wattage on the door is not the wattage you pay for.
LaundryHeat pump against condenser tumble dryer, the real cost per load
A heat pump dryer costs about 39p a load against 66p for a condenser, but the per hour figure everyone quotes is wrong because the compressor never runs flat out.
EntertainmentHow much electricity does a Wi-Fi router use per month if you never switch it off?
A 10 watt router left on around the clock uses 7.3 kilowatt hours a month and costs £1.92 at the current price cap. Here is the arithmetic and why switching it off overnight can backfire.
GardenHow much does it cost to run a hot tub per month in the UK?
An inflatable hot tub held at temperature uses 17.45 kilowatt hours a day on the maker's own test, which is £4.59 a day and £139.70 a month at the Ofgem cap rate. Winter costs more, and switching it off between soaks rarely pays.
HeatingHow much does it cost to run an electric shower for an hour, and per shower?
An 8.5 kW electric shower costs £2.24 to run for a full hour at the Ofgem cap rate, and 29.8p for a normal eight minute shower. The kilowatt figure on the front of the unit is all you need to work out your own.
GardenHow much does it cost to charge an electric car at home per month in the UK?
Charging at home on the standard price cap rate costs about £43 a month for a Tesla Model 3 doing 800 miles, or £49 for a Nissan Leaf. Move the same charging to an overnight EV tariff and the monthly figure drops to about £13.
HeatingHow much does it cost to run an immersion heater per hour in the UK?
A 3 kW immersion heater costs 79.0p an hour at the Ofgem cap rate, and heating a full 120 litre cylinder from cold costs £1.65. A gas boiler does the same job for about 59p, which is why the immersion is usually the backup rather than the plan.
EntertainmentHow much electricity does a gaming PC use per month in the UK?
Three hours of gaming a day on a mid range build costs about £9.48 a month at the current price cap. Leaving the same machine idling around the clock costs another £15 on top, which is the part nobody budgets for.
KitchenHow much does it cost to run a chest freezer per month in the UK?
A 298 litre chest freezer uses 231 kilowatt hours a year, which is £5.07 a month at the Ofgem cap rate. A small 104 litre model costs £4.67 and a tired old unit can reach £8.77, and the energy label tells you which one is sitting in your garage.