Silent diesel generator
for a food trailer.
The generator is the piece of equipment most often bought wrong, and the mistake is nearly always the same: sizing off the kVA number on the label instead of the usable kilowatts, and adding up running loads while ignoring startup surge.
The numbers
- Footprint
- 5 kVA class ~700 × 500mm and 100kg+ — plan where it lives and how it is secured
- New (indicative)
- €1,800 – €8,000
- Used (indicative)
- €600 – €3,500
- Checked
- 2026-08-01
Power figures are ranges across models commonly sold into the Irish trailer trade — read the rating plate on the actual unit before you build a load budget on them. Prices are indicative guidance bands, not quotes, and no supplier is named or implied.
kVA is not kW
Generators are rated in kVA, but appliances are rated in kW, and the two are related by the power factor — typically 0.8. A 3.5 kVA generator therefore delivers roughly 2.8 kW of usable continuous power, not 3.5. Then subtract headroom for motor startup surges from compressors and grinders, which can momentarily draw several times their running figure. The practical rule is to total your running loads, add 30–40%, and buy the next size up from that.
Why silent diesel
Festivals and markets impose noise limits, and an open-frame petrol generator will fail them and annoy everyone within fifty metres including your own customers. A canopied silent diesel unit is the standard for a reason: quieter, more fuel-efficient at sustained load, and longer-lived under the long run hours a festival weekend demands. It is also heavier and more expensive, which is the trade you are making.
Fuel, siting and security
Work out your consumption at realistic load and carry more than that — running out at 7pm on a Saturday is an expensive way to learn. Site the unit downwind of the serving hatch so exhaust does not blow through your food, keep it away from public access, and chain it: generators are stolen from festival sites regularly. Never run one inside an enclosed space or under an awning — carbon monoxide has killed traders.
Questions
What size generator do I need for a food trailer?
Total your running loads in kW, add 30–40% for startup surge, then buy the next size up. Remember kVA is not kW: at a 0.8 power factor a 3.5 kVA generator delivers about 2.8 kW usable. Most LPG-cooking food trailers land at 5–7 kVA; a coffee trailer with a 1-group machine can work on 3.5 kVA.
Why do festivals require silent diesel generators?
Noise limits. An open-frame petrol generator breaches them and is unpleasant for your own customers as well as your neighbours. Canopied silent diesel units are also more fuel-efficient at sustained load and last better over long festival run hours.
Where should the generator go on a pitch?
Downwind of the serving hatch so exhaust does not blow through your food, away from public access, and chained — theft from festival sites is common. Never run a generator inside an enclosed space or under an awning; carbon monoxide is a genuine and repeated cause of death.