If we can use heat sources as energy, why not use it to put power back into the system?
In: Technology
We’ve looked at it. But electricity generation isn’t a great use for it.
Modern electronics are designed to run no hotter than 100 degrees celsius, and even then they’re already thermal throttling (reducing power consumption to keep their temperature under control). Realistically they run in the 60 to 80 degree range at full load. So that’s the sort of temperature we’re working with here.
Water boils at 100. So that’s not hot enough to boil water, meaning a steam engine design is no good. Other heat-based engines, like a Stirling engine, honestly aren’t very good in terms of power output. If room temperature is around 20 degrees, that temperature difference is just too low for most engines to be useful. Furthermore the output would vary by how hard the electronics are working, and an inconsistent power source is a problem of its own.
There are other uses for the heat though. 60 degree water would be good for other applications, like heating a building during the winter, or kicking off general purpose hot water needs. There are datacenters whose heat output is sent to nearby buildings who could make use of it in that regard. So no need to burn natural gas for hot water or other indoor heating, or at least reduced need.
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