Q Is there a greener way to cut grass than burning petrol?

A You bet. Mowers are the gas-guzzlers of the gardening world. At this time of year, as they roll out of garages and sheds, joined by the 375,000 new petrol mowers sold in Britain a year, we need to crack down.

Unlike cars, many petrol mowers don’t have catalytic converters, that masterpiece of antipollution engineering that cuts emissions in half. In 2001 a team of scientists from Stockholm University carried out a survey that concluded that cutting your grass with a lawnmower powered by unleaded petrol for one hour produces the same quantity of polluting emissions as a journey of 100 miles in an average car.

This has not escaped EU legislation. Manufacturers must ensure that their machines meet several European Commission emission directives. The greenest option is to use a push mower, which relies on elbow grease and dramatic demonstrations of male strength – shirts off, sweatbands in place sort of thing. But even Arnie, California’s Governator, might struggle with a large garden to keep under control. In that case, go for an electric mower with a rechargeable battery, or one of the new breed of petrol engines with a catalytic converter. Electric mowers, while producing pollution at the power plant, have no exhaust emissions and reduce noise pollution. The G-Tech electric lawnmower cuts 2,000sq ft on a single battery charge ( mowers-online.co.uk; £129.95). The most appealing option, if you prefer lazy Sunday mornings in bed, is to leave your lawn to hang out. Just let it grow. See it as an exotic wilderness and thriving eco-system. Should your other half think differently, point out that Swedish scientists say that people who drive petrol mowers could be breathing in dangerous carcinogens.

Q Is playing computer games bad for the environment?

A It is my duty to alert you to the fact that Sony’s PlayStation 3 guzzles 200 watts – with an upper limit of 380w – the same as an average PC and an awful lot more than the original XBox game system, which used 74w. You’d be better off with a Nintendo Wii, which requires only 18 watts but uses 9w in standby.

The Energy Saving Trust is compiling a report to show how all this affects CO2 emissions in the UK. It tells me that one of the biggest problems with audio-visual entertainment is our reluctance to switch things off properly, made worse by designs that make the “standby” button easier to use than the “off” button.

By turning off all your appliances at the mains you could save £37 a year on your electricity bills. Even better, switch to a renewable energy supplier, such as Good Energy ( www. good-energy.co.uk) and your electricity will be emission-free.

For Anna’s e-mail address and Eco-Blog, timesonline.co.uk/ecoworrier

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