How Much Does an LPG Generator Cost to Run Per Hour? (UK 2026)
Last updated: June 2026
In 30 seconds:
- A dedicated LPG generator costs roughly £1.73 to £3.12 an hour to run at half load — about £14 to £25 a trading day.
- The 3 kW Greengear is the cheapest to run; the 7 kW costs most because it burns more fuel for the bigger load it carries.
- LPG runs around 40% cheaper than petrol — Greengear’s own figure, and it matches what traders tell us.
- Your real cost depends on the load you draw, not the size on the badge. Don’t buy bigger “to be safe” — you’ll just burn more propane.
Want a figure for your own hours? Try our LPG generator sizing calculator first to pin down the right model, then use the running-cost calculator below.
Most caterers worry about the sticker price of a generator. The bigger number over its life is the fuel. Get the running cost right and you protect your margin on every coffee, burger and box of chips you serve.
Why does running cost matter so much? A food van runs its generator for hundreds of hours a year. Even a 50p-an-hour difference adds up to real money across a festival season.
Why LPG over petrol or diesel? Propane burns cleaner and cheaper. You already carry it on the trailer for cooking, so there’s no second fuel to store or fetch.
The biggest mistake we see? Buying a 7 kW set “to have headroom” and running a 2 kW coffee load through it. The engine loafs, fuel use climbs, and you pay for power you never use. Size to your real draw — the running cost follows.
Quick answer: what an LPG generator costs to run per hour
These figures are for a Greengear dedicated LPG generator at half load, on UK propane at about £2.80 per kg (a 47 kg cylinder). Half load is a fair average for a working day — busy spells push it up, quiet spells pull it down.
| Model | Per hour | Per 8-hour day | 47 kg cylinder lasts |
|---|---|---|---|
| GE-3000UK (3 kW) | ~£1.73 | ~£14 | ~76 hours |
| GE-5000UK (5 kW) | ~£2.79 | ~£22 | ~47 hours |
| GE-7000UK (7 kW) | ~£3.12 | ~£25 | ~42 hours |
Notice the 7 kW costs more per hour than the 3 kW. That’s not waste — it’s carrying a bigger load. The lesson is simple: match the generator to the power you actually draw, and your hourly cost stays low.
Work out your own running cost
Pick your model, your trading hours and your trading days. The calculator shows cost per hour, per day, per month and per year — plus how that compares with petrol and how long a 47 kg cylinder lasts.
LPG Generator Running Cost Calculator
How we work out the running cost
No guesswork here. The figures come straight from the Greengear manual and current UK propane prices. Here’s the simple version.
Step 1 — fuel use per kWh. The manual lists how much propane each engine burns per unit of power: GE-3000UK about 441 g/kWh, GE-5000UK about 398 g/kWh, GE-7000UK about 318 g/kWh. The bigger engines are more efficient per kWh, but they carry bigger loads.
Step 2 — the load. We assume half of the rated output as a working-day average. So the 5 kW model is modelled at 2.5 kW. Your real load could be higher or lower.
Step 3 — the price. We use about £2.80 per kg of propane from a 47 kg cylinder. Multiply fuel use by load by price and you get cost per hour. That’s exactly what the calculator does.
Propane prices move with the market, so treat these as a close estimate, not a fixed quote. When your supplier’s price changes, your running cost moves the same way.
Running cost by model
Greengear GE-3000UK — cheapest to run, for coffee and low-draw setups
- Cost per hour: ~£1.73 at half load (1.4 kW)
- Per 8-hour day: ~£14
- 47 kg cylinder lasts: ~76 hours
- Power: 2.8 kW continuous · 3.1 kW peak
- Weight: 49 kg — a one-person lift
- Price: from £649
Best for: mobile coffee trailers, crepe stands and small market stalls. Low continuous draw, no heavy heating elements.
This is the cheapest Greengear to run because it carries the smallest load. Run a coffee machine, a grinder, lights and a card terminal, and you’ll get a long week out of one cylinder.
Greengear GE-5000UK — the all-rounder for busy food vans
- Cost per hour: ~£2.79 at half load (2.5 kW)
- Per 8-hour day: ~£22
- 47 kg cylinder lasts: ~47 hours
- Power: 5.0 kW continuous · 5.5 kW peak
- Weight: 93 kg — a two-person lift or wheel kit
- Price: from £949
- View the GE-5000UK product page →
Best for: multi-appliance food vans running a fryer, a griddle, lights and ventilation together. Also busy coffee operations with electric water heating.
The 5 kW is the model most traders settle on. It costs a little more per hour than the 3 kW, but only because it does more work. For a typical 8-hour, 5-day week you’re looking at around £110 a week in propane.
Greengear GE-7000UK — for heavy fit-outs and festival pitches
- Cost per hour: ~£3.12 at half load (3.5 kW)
- Per 8-hour day: ~£25
- 47 kg cylinder lasts: ~42 hours
- Power: 7.0 kW continuous · 7.5 kW peak
- Weight: 96 kg — a two-person lift or wheel kit
- Price: from £1,249
Best for: full commercial fit-outs — fryer, griddle, bain marie, lights, ventilation and refrigeration all at once. Hog roast and pizza trailers, and busy festival pitches.
The 7 kW costs most per hour, but it’s the right buy when your appliances genuinely need the power. Run a 2 kW load through it and you waste fuel; run a real 3.5 kW load and it earns its keep.
LPG vs petrol: the running-cost gap
Greengear quotes fuel savings of around 40% versus petrol, and that lines up with what traders tell us. Propane is cheaper per unit of energy, burns cleaner and keeps the engine in better shape.
Take the 5 kW model at 8 hours a day, 5 days a week. On LPG that’s roughly £5,800 a year in fuel. The equivalent petrol set would run closer to £8,100 — about £2,300 more a year for the same power.
There’s a second saving people forget. Petrol means a second fuel to store, fetch and keep away from your food. A dedicated LPG generator runs on the propane already on your trailer — one fuel, one supplier, no jerry cans.
Weighing fuel types in full? Read our guide to LPG vs diesel generators for mobile catering — it covers noise, weight and the red diesel rules too.
How long does a propane cylinder last?
That depends on the model and your load. On a 47 kg cylinder at half load, the 3 kW runs about 76 hours, the 5 kW about 47 hours, and the 7 kW about 42 hours.
A 47 kg cylinder almost always works out cheaper per kg than a 19 kg one, and you change it far less often. The trade-off is weight and space — a full 47 kg cylinder is a serious lift and needs a safe, secured spot on the trailer.
For a full breakdown of which cylinder suits which setup, see our guide to LPG cylinder sizes for mobile catering.
Five ways to cut your running cost
- Don’t oversize. A generator matched to your real load runs efficiently. A big set lightly loaded burns fuel for nothing.
- Stagger your start-ups. Switching everything on at once spikes the load. Bring appliances up one at a time.
- Service it on schedule. A clean air filter and fresh oil keep fuel use down. Check oil daily, clean the filter weekly.
- Buy propane in 47 kg cylinders. Cheaper per kg and fewer changeovers than 19 kg bottles.
- Turn it off in lulls. If there’s a long quiet spell and nothing needs power, shut it down rather than idle.
Why a dedicated LPG generator costs less to run
A “dual-fuel” generator is a petrol engine with an LPG kit added on. A dedicated LPG generator is built for propane from the start. Greengear is the only brand offering purpose-built LPG generators in the UK retail market — every other “LPG generator” here is a petrol unit with a conversion bolted on.
That matters for running cost. A purpose-built engine burns propane more cleanly, holds its rated output, and needs less maintenance over its life. Greengear is a brand within the Cavagna Group — described on its own site as the world’s leading manufacturer of equipment and components for compressed gas control. The propane expertise came first; the generators were built around it.
About Greengear — and what MobCater adds
Greengear’s dedicated LPG generators are factory-built for propane in Brescia, Italy, using the ENERKIT carburetion system engineered with the Cavagna Group. They’re rated for UK outdoor trading from −10°C to +40°C — propane keeps working in the cold, which is exactly why mobile catering uses propane and never butane.
What we add as a UK distributor: pre-purchase appliance-load sizing so you don’t over- or under-buy, cylinder and regulator pairing advice (47 kg vs 19 kg, the right 37 mbar setup), referral to a qualified engineer for your commercial gas safety certificate (CP44), and UK-stock spares — air filters, spark plugs, oil and the ENERKIT carburetor. Warranty is back-to-base on the standard manufacturer terms.
Frequently asked questions
How much does an LPG generator cost to run per hour?
For a Greengear dedicated LPG generator at half load on propane at about £2.80 per kg, expect roughly £1.73 an hour for the 3 kW, £2.79 for the 5 kW and £3.12 for the 7 kW. Your figure depends on the load you draw and your propane price.
How much propane does an LPG generator use per hour?
At half load, the 3 kW burns about 0.6 kg an hour, the 5 kW about 1.0 kg and the 7 kW about 1.1 kg. Lighter loads burn proportionally less. The manual figures are 441, 398 and 318 g/kWh respectively.
How long does a 47 kg propane cylinder last on an LPG generator?
At half load, a 47 kg cylinder runs the 3 kW for about 76 hours, the 5 kW for about 47 hours and the 7 kW for about 42 hours. That’s roughly a full trading week or more for most traders, depending on hours.
Is an LPG generator cheaper to run than petrol?
Yes. Greengear quotes around 40% lower fuel cost than petrol, and traders confirm it in practice. On the 5 kW model running 8 hours a day, 5 days a week, that’s roughly £2,300 a year saved on fuel alone — before you count having only one fuel to store.
Does a bigger generator cost more to run?
At the same proportional load, yes — the bigger engine carries a bigger load, so it burns more propane per hour. But running cost tracks the load you actually draw, not the badge size. Don’t buy a 7 kW to run a 2 kW load; you’ll just waste fuel.
Can I run an LPG generator on butane to save money?
No. Mobile catering uses propane only. Butane stops vaporising below about 2°C, so it fails in cold weather and outdoor trading — useless for a working UK food van. Greengear units are set up for propane at 37 mbar. Stick with propane.
How can I reduce my LPG generator running costs?
Size the generator to your real load, stagger appliance start-ups, service it on schedule, buy propane in 47 kg cylinders, and switch it off during long quiet spells. Each one shaves fuel off your daily cost.
What propane price should I budget for?
Around £2.80 per kg from a 47 kg cylinder is a fair UK working figure, but prices move with the market and supplier. Check your own supplier’s current price and put it into the calculator above for an accurate cost.