Confronted by economic calamity and perhaps the bleakest winter since the 1970s, the most technologically advanced society on Earth is arming itself with the ultimate weapon against recession: the hot water bottle.

With only one moving part (the lid) and the simplest of user manuals (fill with hot water, then snuggle), the humble hottie has been embraced by Japan’s emerging national thriftiness. They are cheaper than central heating, immune to volatile commodity prices and, say their millions of new converts, the perfect solution to a bout of depression. From the most sophisticated department store in the fashionable Ginza district of Tokyo to the lowliest bargain shop, consumers have, in the past five weeks, cleared the shelves of every hot water bottle.

Traditional hard-cased yutampo, Western-style rubber bottles and even miniature flasks for people on the move are enjoying unprecedented popularity.

October hot water bottle sales in Hokkaido, the most northern and coldest part of the country, are 260 per cent higher than this time last year and represent one of the few areas of the Japanese consumer economy that is still growing. Mitsukoshi, the Harrods of Tokyo, is selling a copper hot water bottle for the equivalent of about £100. Younger Japanese, however, are likely to head next door to the Sony Plaza, where cartoon-themed ones are on sale for a more modest £25. The skint may be more tempted by the plain, plastic offering going for a fiver at Muji, the household goods store.

A spokesman for the Tokyu Hands department store in the Shibuya district said that the boom was playing on the dual concerns of lower electricity usage and environmental consciousness. One hot water bottle used instead of a night’s central heating will apparently save the equivalent of 30kg of carbon dioxide emissions a year.

In these hard times, say makers of the hard-shelled yutampo, an industry that once shifted a million units a year – mainly to the elderly – is expecting sales of more than three million.

The trend will make worrying reading for Japan’s struggling electronics industry, which has spent years perfecting computer-controlled air-conditioning systems, electric bed-warming gadgets and even self-heating carpets – but the natural instinct to innovate and improve has not disappeared entirely: one company has designed a hot water bottle that can be worn like shoes.

MEAN TRICKS

- Shower Clean Suits, by Konaka, are washed under a warm shower to save on dry-cleaning costs

- Socks sold in packs of three, so that when one develops a hole, the spare can be used

- A water pipe to carry warm bath water for use in the washing machine

- A thick ring of stainless steel for the inside of a toilet cistern, uses 40 per cent less water

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