How much does a shower cost to run? Electric and power showers compared
Here is the oddity at the heart of this comparison: the shower with 'power' in its name draws almost no electrical power, while the plain electric shower is one of the hungriest appliances in the house.
A 9.5kW electric shower out-pulls most ovens; a power shower's pump sips a few hundred watts. Yet that isn't the end of the sums, because the power shower's costs arrive through a different pipe entirely.
This guide works the numbers properly: what each type draws, what a ten-minute shower costs at the current energy price cap, where a water meter changes the answer, and which one your particular home runs cheaper. All figures use the July to September 2026 cap rates of 26.11p per kWh for electricity and 7.33p for gas. The cap resets each quarter, so rerun the sums with your own unit rates when they change.
The comparison at a glance
| Electric shower | Power shower | |
|---|---|---|
| What heats the water | Its own element, on demand | Your cylinder, via boiler or immersion |
| Electrical draw | 7.5kW to 10.5kW | A pump of a few hundred watts |
| Circuit needed | Dedicated high-current circuit | Ordinary fused connection unit |
| Electricity per 10-minute shower | About 1.3 to 1.75kWh | Around 0.05kWh |
| Water per 10 minutes | About 50 litres | About 120 litres |
| Works with a combi? | Yes | No |
Power draw: the name points the wrong way
An electric shower is a tankless water heater with a spray on the end. Everything you feel as warmth was made seconds earlier by an element rated between 7.5kW and 10.5kW, and moving that much electricity safely is why an electric shower needs its own dedicated circuit and noticeably thick cable. Run one for ten minutes at 9.5kW and it consumes about 1.6kWh.
A power shower makes nothing; it moves. The heating already happened in your cylinder, so the only electricity the unit itself uses drives a small pump motor, which is why it connects through an ordinary fused spur rather than heavy cable. Over the same ten minutes the pump accounts for around 0.05kWh: just over a penny at current rates. On electrical draw alone the comparison isn't close, but electrical draw alone is the wrong way to count.
What a ten-minute shower costs, worked through
The arithmetic needs assumptions, so here they are: a ten-minute shower, water warmed by 25°C, the electric shower rated at 9.5kW, the power shower flowing at 12 litres per minute, and a gas boiler running at 85% efficiency where the cylinder is gas-heated. Change any of them and the answer moves, but the shape of the comparison holds. The sums use unit rates only; standing charges apply whether you shower or not, so they don't alter the comparison.
The electric shower is the easy sum. 9.5kW for a sixth of an hour is 1.58kWh, which at 26.11p per kWh comes to about 41p, or a little over 4p per minute. Across the common ratings that's a band of roughly 33p at 7.5kW to 46p at 10.5kW.
The power shower's sum runs through the gas meter. Ten minutes at 12 litres per minute is 120 litres, and warming that by 25°C takes about 3.5kWh of heat, which a gas boiler delivers by burning roughly 4.1kWh of gas: right around 30p at 7.33p per kWh. Add the pump's penny and a gas-heated power shower lands near 31p, cheaper than the electric shower despite using more than twice the energy, because a unit of gas costs barely more than a quarter of a unit of electricity.
One caveat carries the whole verdict: that 30p assumed gas. If your cylinder heats by immersion, the same 3.5kWh of warmth is bought at the electricity rate and the shower costs around 90p, more than double the electric shower. Immersion-heated homes should read the rest of this comparison with that number in mind.
Scaled to a year, the pence become bills. One ten-minute shower a day comes to about £150.00 on a 9.5kW electric shower, £113.00 on a gas-fed power shower, and £332.00 where an immersion heats the cylinder; on a water meter the all-in figures run to roughly £215.00 and £266.00 respectively. Multiply by the number of showerers in the house and the gaps turn into real money: for a family of four, the metered difference alone is around £200.00 a year.
Water: the cost the meter sees
Flow is the power shower's whole point, and flow is litres. Twelve litres a minute against an electric shower's five or so means the same ten minutes uses about 120 litres against 50. In an unmetered home that difference costs nothing and you can skip this section. On a meter, every litre is billed twice, once as water and once as sewerage, and at a combined rate of £3.50 per cubic metre (a mid-range figure; your bill states yours) those extra 70 litres add roughly 25p to each shower.
Fold that in and the picture flips. The gas-heated power shower climbs to about 73p all-in once its 120 litres are billed; the electric shower reaches roughly 59p with its 50. On a meter the electric shower usually edges it, and shower length drives the gap, at about 7p per pumped minute against 6p per electric one. Off a meter, the gas-fed power shower is the cheaper route to a far stronger soak.
Installation: the other bill
Purchase prices overlap, so the fitting is where budgets diverge. An electric shower's expense is electrical: a new dedicated circuit from the consumer unit, sized to the kilowatt rating, is a substantial piece of notifiable work for a registered electrician, though the plumbing is a single cold feed. A power shower reverses the weighting: its electrical connection is a modest fused spur, but the pipework wants dedicated hot and cold feeds and a cylinder flange, which in a home without them is the larger share of the job. The cheaper install is usually whichever set of pipes or cables your house already has.
Cutting the cost of either
Minutes are the biggest lever on both machines. Every minute costs an electric shower about 4p and a metered power shower about 7p, so a household that trims ten-minute showers to seven claws back a quarter to a third of the bill without touching the hardware. On power showers, eco modes do something similar automatically, trimming flow while keeping the pressure sensation, and they suit the one long daily soak rather better than willpower does.
The cylinder is the power shower's hidden dial. Because its running cost is really the cost of hot water, anything that makes the cylinder cheaper makes the shower cheaper: a thermostat set to 60°C rather than higher, an insulating jacket on an older tank, and, for immersion-heated homes, a time-of-use tariff that heats the water in the cheap overnight window. The electric shower has no equivalent trick; its element buys electricity at whatever the rate happens to be the moment you shower, which at least makes an off-peak tariff interesting for early risers.
When each one wins
The decision map is short. A gas-heated cylinder and no water meter is power-shower territory: the strongest flow at the lowest marginal cost. A water meter tilts the running costs to the electric shower, and an immersion-heated cylinder tilts them decisively. No hot supply near the bathroom makes the electric shower the practical answer regardless of cost, and a combi boiler rules the power shower out entirely; fit a thermostatic mixer and let mains pressure do the work. Where both types genuinely suit your plumbing, choose on what you value: the electric shower is the frugal workhorse, the power shower is the better ten minutes.
Shower running cost FAQs
How much does an electric shower cost per minute?
At the July to September 2026 cap rate of 26.11p per kWh, a 9.5kW electric shower costs a little over 4p per minute of hot water; an 8.5kW unit is nearer 3.7p and a 10.5kW unit about 4.6p. A ten-minute shower therefore sits in the 37p to 46p range across those ratings, before any metered water is counted. The kW rating is printed on the front of most units, so the sum for your own shower takes seconds.
Do power showers use a lot of electricity?
No, and the name misleads. The pump inside a power shower is a small motor that adds about a penny to a ten-minute shower at current rates; there is no heating element drawing kilowatts. What a power shower does use a lot of is hot water, and the cost of making that water, by gas boiler or immersion, is where its real running cost lives.
Does turning up an electric shower's temperature cost more?
Usually not, which surprises people. On most units the temperature dial changes the flow rate, not the power: the element draws its full rating whenever the shower runs, and a hotter setting sends less water past it. The cost is set by kilowatts and minutes. The exception is units with selectable power settings, where a low or eco setting genuinely runs part of the element and does cut the draw.
Is it cheaper to have a bath or a shower?
It depends on how each is heated and how long the shower runs. A standard 80-litre bath heated by gas costs about 20p in fuel, which beats a ten-minute 9.5kW electric shower at 41p and roughly matches a ten-minute gas-fed power shower before water charges. Shorten the shower and it wins: four electric minutes cost about 17p. The honest rule is that brief showers beat baths, long pumped showers don't, and gas heating beats electric heating whichever vessel it fills.
Which is cheaper to install, an electric or a power shower?
It depends on what your home already has. The electric shower's big line item is a dedicated high-current circuit; where a suitable one exists from a previous unit, installation is quick, and where it doesn't, the circuit is the dearest part of the job. The power shower's cost centre is pipework: dedicated hot and cold feeds and a cylinder flange. Homes replacing like for like get the cheapest install of all; switching between the two types is where the bills grow.
Whichever way your sums point, Shop power showers, compare electric showers by power rating, or start with the difference between electric and power showers if the choice itself is still open. Our complete power shower guide covers the wider decision beyond cost.
Plumbworld has priced both types keenly since 1999, with a price match promise and free UK delivery, so the running costs are the only sums you need to sharpen.
Big brands, small prices.