4 ms·
Waste heat usage has been a thing since around the time we invented the steam engine. Regenerative heating was in fact key to the first industrial revolution,
by semi-extrinsic 9y ago
Waste heat usage has been a thing since around the time we invented the steam engine.
Regenerative heating was in fact key to the first industrial revolution, it was the only way to make blast furnaces with high enough temperature and power.
It's only recently that datacenter power usage (and thus waste heat) has become large enough for waste heat usage to be interesting.
- ZeroGravitas 9y agoSince before the steam engine even: https://en.wikipedia.org/wiki/Kang_bed-stove https://en.wikipedia.org/wiki/Kang_bed-stove
- hkmurakami 9y agoI'm pretty sure my college used the heat product from its cogeneration plant on campus to heat our buildings and dorms. Actually, that was probably already a thing when Bezos was a student there.
- IgorPartola 9y agoA lot of colleges use cogeneration plants. Almost nobody else does. From what I understand, it nearly doubles the total efficiency of burning coal, though the output is not more electricity but heat. The physics is pretty simple as explained by the Carnot cycle [1]: Efficiency <= 1 - Tc / Th, where Tc is the cold exhaust temperature and Th is the hot temperature. This is of course a theoretical ideal engine. The issue is that for something like a coal or oil or gas plant, Tc is still damn hot. Something like 900 degrees F is common. It's too low to use for a second cycle of electricity usage, but it's still plenty hot to heat your living room. [1] https://en.wikipedia.org/wiki/Thermal_efficiency#Carnot_efficiency https://en.wikipedia.org/wiki/Thermal_efficiency#Carnot_effi...
- khuey 9y agoA good portion of Manhattan has a steam system that's partially fed by cogeneration.