Battery vs petrol lawn mowers

Battery and petrol at a glance

The table uses widely known features of each type rather than one model's specs.

Cut quality in long, wet grass

Long, damp grass is the hardest test for any mower. A petrol engine keeps delivering power until the tank is empty, which is why petrol remains popular for big rough lawns and paddocks. Battery mowers cope well with regular cutting, and higher voltage brushless models handle heavier growth, but wet grass increases the load, shortens run time and can clog the deck faster.

The best fix works for both: mow dry grass where possible, raise the cutting height for the first pass and follow the RHS one-third rule so you never remove more than a third of the height at once. Our one-third rule tool works out the steps from long grass back to your normal height.

Noise, starting and servicing

Battery mowers are noticeably quieter because there is no engine, which matters for early starts and close neighbours. They start with a safety key and a lever or button, with no choke and no pull cord.

A petrol mower needs regular care: oil checks and changes, a clean air filter, a working spark plug and fresh fuel. Many owners have it serviced by a dealer once a year. Battery mowers need far less, mostly a sharp blade, a clean deck and sensible battery storage.

• Battery upkeep: sharpen or replace the blade, brush out the deck, store packs indoors.
• Petrol upkeep: oil, air filter, spark plug, blade, fuel stabiliser or empty tank for winter, annual service.

Running costs in kWh and litres

Running costs are best compared in energy, not money, because prices change. A battery mower uses the energy stored in its pack: watt hours equal volts multiplied by amp hours. A 60 V 8 Ah pack, as supplied with the Hayter Harrier 48 AD, holds about 480 Wh, so recharging it from flat takes roughly half a kilowatt hour plus charger losses. Smaller packs use proportionally less.

A petrol mower uses litres of fuel plus engine oil. Consumption depends on engine size, grass and how long you mow, so the simplest way to know your own figure is to note how many litres you add over a season. Petrol also needs storing safely, and fuel left for months can go stale and cause starting problems.

Safety and fuel storage

Petrol is a fire risk. Store it only in containers designed for petrol, away from the house, boilers and any source of ignition, and refuel outdoors with the engine off and cool. The HSE publishes guidance on how much petrol can be kept at home and in what containers. Battery packs need care too: use the maker's charger, charge away from heat and do not use a damaged pack.

Note:Before touching the blade or clearing the deck, remove the battery or safety key on a battery mower, or disconnect the spark plug lead on a petrol mower, and wait for the blade to stop. Wear gloves and never tip a running mower. On a petrol mower, tip it only as the manual describes to avoid oil or fuel leaks. Leave engine repairs to a dealer or qualified service agent.

Which should you choose?

Choose battery for small to large domestic lawns cut regularly, where quiet running and low upkeep matter. A wide deck with self drive and spare batteries can cover a large garden: see our large garden cordless mower guide, or our best cordless lawn mower guide for all sizes.

Choose petrol for very large or rough areas, long grass cut only occasionally, or where you need to mow for hours without stopping. If you mostly want the lawn kept short with little effort, a robot mower is also worth a look: our best robot lawn mower guide covers them.

Frequently asked questions

Are battery lawn mowers better than petrol? For most domestic lawns cut every week or two, yes: they are quieter, start instantly and need less servicing. Petrol still suits very large or rough areas.

Do battery mowers cut wet grass? They can, but wet grass drains the battery faster and clogs the deck. Mow dry grass where possible and raise the cutting height.

How long do battery mowers last compared with petrol? Both can last many years with care. The battery pack is the part that wears over time, and it can be replaced on its own.

Is it cheaper to run a battery mower? A recharge uses a small amount of electricity, measured in fractions of a kWh for most packs, and there is no oil or engine servicing. Check current energy and fuel prices to compare.