Daily Archives: February 12, 2008

Waste heat

Just mentioned this on IRC … and it occurs to me that it’s something the chattering classes don’t seem to have noticed. Perhaps if I blog about it, someone might.

Heat exchange is a lot more efficient than generating heat. So we should be using heat exchangers to harness far more of the heat that we generate. Some slight efforts have been made in this direction with combined heat and power, and with harnessing industrial heat for heating living or working space.

On the other hand, all the heat from my computer goes to waste. That on its own is fairly negligible, but in a big data centre that’s a lot of heat. Surely it’s time for server, rack, and other infrastructure-manufacturers to incorporate water-cooling pipes, so that their waste heat can be pumped into an exchange? The industry should adopt a standard size and placement for cooling pipes, so that components can slot together and just work.

With Nature’s heat, it’s the same story. Geothermal heat is popular in some of the most obvious places, like volcanic Iceland where it’s abundant and cheap. But heat exchange works even where there isn’t that extra natural heat: for example, in the UK, it can drastically reduce the energy required to heat a building. Not something you can easily retrofit, but it’s a shame to see it being ignored in new buildings.

One thing I would like to retrofit, if I had a garden, is a heat-exchange with a compost heap. That should be relatively easy, and compost generates lots of heat. Should work well for heating water, or feeding into a heating system.

Sounds like a great class of technology project for sixth-formers or college students with practical abilities. Any students or teachers listening? What are you doing?