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Comment by horsawlarway | Hacker News Reader

Exactly this.

And the same thing for residential scale is literally just a ceramic space heater running at ~1500w.

They're dirt cheap, usually have temp safety checks built in, work on a residentially sized circuit, and are available everywhere.

I needed a cheap and consistent load to do LFP battery testing, and I could spend $5,000 for a real test unit, or $21 for a ceramic heater that will do basically the same thing.

If you've already got the monitoring for the batteries/inverters, a heater is a GREAT load choice.

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HAAS CNC mills are famous for using electric stove elements for the spindle brake resistor: https://www.reddit.com/r/CNC/comments/1es1d01/someone_didnt_...

I'm not sure that this really is a completely off-the-shelf stove element. But obviously, the technology is basically identical to what you'd have on your stove.

It is cery common for Frequency Inverter for AC Motors to have a break resistor. It's expensive to push energy back to the grid with from an inverter. So in most case just a break resistor is used. Just if you break a lot and a long time it is worth to buy an inverter who can do it. If you have multiple axis in a machine, often they are coupled with DC, so the break energy is used by another drive.

Yup. On a much bigger scale it's common for the power supplies going to electric trains to do this too. They like to use regenerative braking because it's efficient. But the electricity grid can't always handle the extra power, so in some designs they have a backup mechanism to dissipate the power if needed; diesel-electrics usually just have a big bank of air-cooled load resistors on the roof.

A neat example of regenerative braking being important is the London Underground: they've had a persistent problem with high temperatures in the subway, of which a decent % is actually heat from trains braking. By using regenerative braking rather than putting that energy into the tunnels as heat, they can transport that energy outside the tunnels, keeping them cooler.

so you're installing a resistive heater? what is the economics of that?

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