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Comment by ksherlock | Hacker News Reader

It's not waste heat if you only run it in the winter.

Opt if you ignore that both gas furnaces and heat pumps are more efficient than resistive loads.

Heat pump sure, but how is gas furnace more efficient than resistive load inside the house? Do you mean more economical rather than more efficient (due to gas being much cheaper/unit of energy)?

Depends where your electricity comes from. If you're burning fossil fuels to make electricity, that's only about 40% efficient, so you need to burn 2.5x as much fuel to get the same amount of heat into the house.

Sure. That has nothing to do with the efficiency of your system though. As far as you are concerned this is about your electricity consumption for the home server vs gas consumption. In that sense resistive heat inside the home is 100% efficient compared to gas furnace; the fuel cost might be lower on the latter.

Sure, it's "equally efficient" if you ignore the inefficient thing that is done outside where you draw the system box, directly in proportion to how much you do it.

Heating my house with a giant diesel-powered radiant heater from across the street is infinitely efficient, too, since I use no power in my house.

If you don’t close the box of the system at some point to isolate the input, efficiency would be meaningless. I think in the context of the original post, suggesting running a server in winter would be a zero-waste endeavor if you need the heat anyway, it is perfectly clear that the input is electricity to your home at a certain $/kWh and gas at a certain $/BTU. Under that premise, it is fair to say that would not be true if you have a heat pump deployed but would be true compared to gas furnace in terms of efficiency (energy consumed for unit of heat), although not necessarily true economically.

Generating 1kWh of heat with electric/resistive is more expensive than gas, which itself is more expensive than a heat pump, based on the cost of fuel to go in

If your grid is fossil fuels burning the fuel directly is more efficient. In all cases a heat pump is more efficient.

I think this is pretty silly either way.

- There's an upstream loss on electricity directly in proportion to how much you use; ignoring this tilts the analysis in favor of electricity.

- You pay more for heat from electricity than gas, in part because of this loss.

It’d be fun to actually calculate this efficiency. My local power is mostly nuclear so I wonder how that works out.

You accelerate the climate catastrophe so there's less need for heating in the long run.

I'm in the market for an oven right now and 230V/16A is the voltage/current the one I'll probably be getting operates under.

At 90°C you can do sous vide, so basically use that waste heat entirely.

For such temperatures you'd need a CO2 heat pump, which is still expensive. I don't know about gas, as I don't even have a line to my place.

90C for sous vide??? You're going to kill any meal at 90.

Make it "up to 90°C". 5th quarter meats are better done in the higher end of sous vide temperatures.

Point being, you can throttle your equipment to the desired temperature and use that energy effectively.

How can you bear to eat sous vide though? I've tried it for months and years, and I still find it troublesome. So mushy, nothing enjoy.

Did you skip searing it after sous vide? Did you sous vide it to the "instantly kill all bacteria" temperature (145°F for steak) thereby overcooking & destroying it, or did you sous vide to a lower temperature (at most 125°F) so that it'd reach a medium-rare 130°F-140°F after searing & carryover cooking during resting? It should have a nice seared crust, and the inside absolutely shouldn't be mushy.

Please research this. Done right, sous vide is amazing. But it is almost never the only technique used. Just like when you slow roast a prime rib at 200f, you MUST sear to get Maillard reaction and a satisfying texture.

Seasonality in git commit frequency

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