A: Guilt-free taxi travel sounds pretty good, doesn’t it? Of course, this is the point where I should clear my throat and declare, in a stern voice, that the only true eco-taxis are bicycles. But for the lite-greens, yes, a new concept has come to town.

So far it has hit only London. Tom Packenham and Jonny Goldstone, two former City lawyers, have launched the Green Tomato cab service (www.greentomatocars.com).

Based in Hammersmith, West London, its fleet of Toyota Prius cars — which have combined petrol and electric engines — serves the western half of London but there are plans to expand to the whole city by the end of the year. In traffic, and at low speeds, the vehicles rely on an electric engine, cutting carbon emissions and noise pollution. Charging no more than other London taxi firms, it will, nonetheless, plough money into climatecare.org to make the company carbon neutral.

The black cab firm radiotaxis.co.uk, which operates 3,000 cars across the capital, made a similar commitment to being carbon neutral last year: it attributes a bumper financial year to this. Good reason for others to head down that road.

Q: Is there a good, eco-friendly way to keep moths at bay?

A: A new season, a new eco-quandary, eh? Everyone loves bagging up the winter woollies and tucking them away in dark corners of the house, but spring is the peak egg-laying season for moths. The chance to nestle down in our favourite cashmere jumpers is irresistible (as the snobs of the insect world, they munch only natural fibres).

So it’s time to find a natural moth-repellent. Cedar balls, which release natural oils from the wood, and lavender sachets are both good. I like Colibri’s Lavender Sachets (www.lakelandlimited.co.uk; £3.95).

Natural solutions do work, says the British Pest Control Association, but, if you spot any holes in your clothes or any sign of these creatures, you’ll need to kill the larvae by putting all your clothes in polythene bags, squeezing out the air and freezing them for 72 hours. This is greener than laundering them at high temperatures — the other effective solution.

You may find yourself cursing the 2002 ban of conventional mothballs. But we’re better off without them. They contain dichlorvos, a chemical that has been linked to damage to the human nervous system. Dichlorbenzene (1,4) slipped the net (try Waitrose, if you must), but a recent EU report concluded that there was a need for limiting its risks on health, mentioning a possible ban.

Much better to nurture some crafty granny chic and stitch your own lavender bags. Words I thought I’d never say.

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