With the cost of gas skyrocketing, people will be trying to ride bikes soon. But being out of shape or just riding in hot environments many of these will give themselves heat stroke. Instead, mount a roller to push up against a wheel. Attach a sterling cycle engine to the roller to run in reverse. This will cause cooling. By cooling a fluid and pumping this through pipe embedded underwear the rider can pump heat away from their body. They might even get to work without being soaked in sweat.

This would require achieving a COP of greater than one, not that difficult with a sterling cycle to fluid at body temperature. Dumping the heat on the other side would be the trick. It could also be done with motorcycles, scooters and smaller engine driven vehicles. Once wearing such underwear became common, personal heating and cooling could be supplied in offices, factories etc. instead of heating and cooling the air of buildings.

If you put the bike on a frame and attached a super insulated box one could create a bicycle powered refrigerator for remote areas. This could be useful at refugee camps, villages needing refrigerated storage of medicines or stuff and campers storing the catch of the day.
-- cjacks, Oct 01 2005

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