Yesterday The Times reported that the rising price of raw materials has finally made recycling a profitable industry. The turnover of the waste industry has jumped by two thirds in two years from £1.2 billion to £2 billion. But the notion that recycling makes economic sense is rubbish.

Some things are profitable to recycle, some things only make sense to recycle when we consider the environmental effects, some things we would be crazy even to try to recycle. Working out what falls into each category should be done by cost-benefit analysis. Add up all the costs, then all the benefits, and see which outweighs the other.

Local authorities in England are spending £3 billion a year dealing with 30 million tonnes of waste. We also see revenues from recycled rubbish of £2 billion a year.

However, there is one cost that no one acknowledges: the time spent preparing items for recycling. No one mentions it because it's done by you, free, in your own home.

The best estimate of the time that a household spends on sorting items for recycling - not only run-of-the-mill household rubbish but food and garden waste too - is 45 minutes each week. There are 24 million households, so that adds up to 900 million hours of unpaid labour every year. Unpaid, yes, but not of no value: thanks to the minimum wage, the Government forbids you from selling your time for less than £5.35 an hour. So the value of all that recycling by the general public must be worth at the very least £5 billion a year.

So our waste management system costs us £8 billion - and in return we get back £2 billion by selling the recycled goods. A £6 billion total cost.

If we did not sort to recycle then we would lose that revenue - but also be relieved of the unofficial cost of us all sorting through our rubbish. A non-recycling waste disposal system would cost us £3 billion. Recycling is therefore twice as expensive as simply throwing the whole lot into holes in the ground; and it thus makes us poorer.

So why do we do it? That brings in the EU and its laws that fine us if we don't become less reliant on using landfill. But we have no shortage of possible landfill sites: we dig up some 110 million cubic metres (mcm) of sand, gravel and clay every year; and each year we produce some 100 mcm of waste. We could stick the waste in those holes if it weren't for those European Commission fines.

Saving resources is good, of course. But in doing the sums we have ignored that most valuable resource of all, time. To be more precise, our time.

Tim Worstall blogs at timworstall.com

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