A 13kW gas patio heater costs a pub about £3.90 an hour to run on Calor's current patio gas price, which is about a pint and a half of profit every hour it's lit. A 2kW electric infrared heater costs about 57p an hour on a typical small-business electricity rate, or a quarter of a pint. Per unit of heat they're almost exactly the same price, around 29p to 30p a kWh. The difference is where the heat goes, how long it's left on, and whether anyone's sat under it.
Look this up and you get home-and-garden pieces from 2023 using the household price cap. Pubs don't get a price cap, pay different VAT on gas bottles than on electricity, and leave heaters on for six hours on a Saturday. So here are the sums done properly for a pub, with October 2026 prices, and the one-line test that tells you whether a heater is paying its way.
Gas: what a bottle buys you
Calor's 13kg Patio Gas refill is £52.50 when you swap an empty, plus a temporary surcharge of £1.31 on LPG bottles. That's £53.81. Calor's prices include VAT, and bottled LPG in cylinders under 50kg is one of the supplies HMRC's fuel and power notice puts at the reduced 5% rate.
A typical commercial mushroom or pyramid heater is rated at 13kW. The Dellonda DG1 lists "Fuel Consumption: 945g/hr" at full output, and the electriQ 13kW pyramid gives "928–945g/h". So:
- 13kg ÷ 0.945kg an hour = 13.8 hours per bottle on full
- £53.81 ÷ 13.8 hours = £3.91 an hour, including VAT
- If you're VAT registered and reclaim the 5%, it's £51.25 a bottle and £3.72 an hour
Most heaters have a dial and fewer people run them on full than think they do, so on a low setting you'll do better than this. But full is how most of them get left.
Electric: what a kilowatt-hour costs a pub in 2026
There's no price cap for business energy, so your rate is whatever your contract says. The Catalyst business energy cost index for April to June 2026 puts the average non-domestic electricity price at 24.51p a kWh, with small businesses at 28.59p and micro businesses at 38.36p, including the Climate Change Levy. A wet-led local usually sits in the small or micro band.
| Heater | At 24.51p (average) | At 28.59p (small business) | At 38.36p (micro business) |
|---|---|---|---|
| 1.5kW | 37p | 43p | 58p |
| 2kW | 49p | 57p | 77p |
| 3kW | 74p | 86p | £1.15 |
A quick word on VAT, because the news has muddied it. Electricity in Great Britain went to a temporary 0% VAT rate from 1 October 2026 to 30 June 2027, extended at the Budget. That's only for "qualifying" supplies: homes, charities and businesses using no more than 33kWh a day on average. A pub uses far more than that, so a normal pub supply is still 20%, which you reclaim if you're registered. Check your bill rather than assume.
Side by side, per hour and per pint
I've used the same pint as the rest of my overheads guides: a £5.34 pint leaving about £2.45 of gross profit.
| Heater | Cost per hour | Pints' profit per hour | Four heaters, 6-hour night | In pints |
|---|---|---|---|---|
| 13kW gas, full | £3.72 ex VAT | 1.5 | £89.28 | 36 |
| 2kW electric, small business rate | 57p | 0.23 | £13.72 | 6 |
| 3kW electric, small business rate | 86p | 0.35 | £20.58 | 8 |
Four gas heaters on a Saturday night are 36 pints of profit before you've earned a penny out there. Over a 26-week winter of Fridays and Saturdays that's £4,643, or about 1,900 pints. That's the number to have in your head when you're deciding whether to light them.
Why the cheaper one isn't simply "electric"
Here's the bit I didn't expect when I did the sums. Work it out per kWh of heat and they're neck and neck:
- Gas: 13kW for 13.8 hours is about 179kWh of heat for £51.25 ex VAT. About 28.6p a kWh.
- Electric: 28.59p a kWh at the small-business rate.
So the gas heater isn't expensive because gas is dear. It's expensive because it's big, 13kW against 2kW, and because of where the heat goes. A mushroom heater warms the air around it, and outside the air doesn't stay put. Infrared heaters warm people and tables directly; Tansun, a UK maker, says they "directly heat the people and objects instead of the air around". That's a manufacturer's claim, but it's the right principle. Herschel's own spec sheet is honest that wind cuts it too: "infrared spread may reduce by 1/3 to 1/2" in windy areas.
What that means in practice: for a covered, sheltered area where people sit still, a couple of 2kW infrared heaters aimed at the tables will feel warmer per pound than one gas mushroom in the middle. For a big open garden in a wind, nothing works brilliantly, and gas at least needs no cable run.
The safety rule for covered areas
If your heaters live under a canopy or a gazebo with sides, read the manual. The Dellonda manual says "the use of this heater in enclosed areas is dangerous and is prohibited", and defines an amply ventilated area as one "that has a minimum of 25% of the surface area open". Pull the winter sides down on a gazebo and you can drop below that without noticing. That's when you switch the gas heater off, not when you turn it up.
The test: is a heater paying its way?
One line. A heater pays when the people under it buy more profit than it burns. A full gas heater needs about 1.5 pints an hour sold to the people it's warming. Two people having one drink each an hour clears it. An empty table under a lit heater doesn't.
So the money isn't in choosing gas or electric. It's in the hours nobody's there. A gas heater left on for two hours after the table's gone in costs £7.44, three pints. Four of them, most nights, and it's a staff wage. What I'd do:
- On when someone sits down, off when they leave. Make it part of collecting glasses outside.
- Put electric ones on a push-button or a timer so they can't be left on overnight.
- Count it for two weekends. Heater hours on one side, drinks sold outside on the other. If the heaters are costing more than the outside trade makes, you've got your answer, and it might be a stack of blankets.
Some pubs charge for heaters, a pound for half an hour on a meter. I'd rather not charge regulars to be warm, but if you've got a big garden of people nursing one drink all evening, it's an option.
Heaters are one line in a list of overheads that all come out of the same pint. My electricity cost per pint guide has the cellar and lighting side, the Sky Sports guide does the same sum for your screens, and whether to open on quiet nights puts them together. If you're thinking about music out there too, read the rules for playing music outside first.
My take
Gas or electric matters less than people think, because per unit of heat they cost the same. What matters is size and switching off. Pick heaters that warm the tables people sit at, turn them off when the table's empty, and check the gas ones are never running under closed sides. Do that and a winter garden can earn its keep. Leave four mushrooms burning to an empty patio and you're giving away 36 pints a night.
Common questions
How much does a patio heater cost to run per hour?
A 13kW gas heater on full costs about £3.91 an hour at Calor's £52.50 refill price plus the £1.31 surcharge. A 2kW electric infrared heater costs about 57p an hour at a small-business rate of 28.59p a kWh, before VAT.
How long does a 13kg patio gas bottle last?
About 13.8 hours on full in a 13kW heater using 945g an hour. Longer on a lower setting.
Is gas or electric cheaper for a pub beer garden?
Per kWh of heat they're almost the same, around 29p. Electric infrared is usually cheaper in practice because the heaters are smaller and aim heat at people, not the air. Gas is easier where there's no power supply.
What VAT does a pub pay on patio gas and electricity?
Bottled LPG in cylinders under 50kg is at the reduced 5% rate. A normal pub electricity supply is 20%, as pubs use more than the 33kWh a day limit for the temporary 0% rate. Registered pubs reclaim both.
Can you use a gas patio heater under a gazebo?
Only if it's amply ventilated. One manufacturer's manual defines that as at least 25% of the surface area open, and prohibits use in enclosed areas.
Sources
- Calor 13kg Patio Gas £52.50 refill, 5kg £23.25: Calor shop, checked 30 October 2026. £1.31 temporary LPG surcharge: Calor 13kg Patio Gas product page. Prices include VAT: Calor LPG prices.
- Dellonda DG1 13kW, 945g/hr: Lawson HIS listing. Enclosed-area warning and 25% open definition: Dellonda DG1/DG2 instructions.
- electriQ 13kW pyramid heater, 928 to 945g/h: Appliances Direct listing.
- Business electricity Q2 2026: average 24.51p, small 28.59p, micro 38.36p a kWh including Climate Change Levy: Catalyst Commercial business energy cost index. No price cap on business energy: Bionic.
- LPG in cylinders under 50kg at the reduced rate, 33kWh a day electricity limit, temporary 0% rate 1 October 2026 to 30 June 2027 for qualifying supplies: HMRC, VAT on fuel and power (Notice 701/19), updated 28 October 2026.
- Infrared heats people and objects: Tansun patio heating (manufacturer's claim). 2kW rating and wind reducing spread: Herschel California.
- £2.45 gross profit on a £5.34 pint: my electricity cost per pint guide.
- All per-hour, per-kWh, per-pint and per-season figures are my own arithmetic from the prices above. Your contract rate will differ, so put your own in.