Perhaps not all of it is entirely "wasted" though. I've largely been able to avoid heating this winter as a result of crypto mining.
A computer pumping ~300W into the air 24/7 is remarkably effective for a small apartment
A computer pumping ~300W into the air 24/7 is remarkably effective for a small apartment
If your using fossil fuels for heat its more efficient to burn them directly at point needed and capture the heat, rather than use the heat to convert to mechanical then electrical then back into heat.
Air source heat pumps are basically solar assisted, they move heat from outside air into heated space using electricity which also contributes resistive heat in compressor friction. The outside air is heated by the sun.
This is not true. Resistive heating is inefficient indeed but not all forms of conversion of electricity are inefficient. Geothermal pumps are very efficient for instance and use electricity only, they can be assisted directly by solar (PV) too.
Doesn't mean that the generator on the other end is efficient but that is a separate concern that can benefit from economies of scale (a big gas turbine would be more efficient than a swarm of small gas ovens producing the same energy).
Simple proof by example; if the exhaust air of your gas oven is warmer than ambient energy, it cannot be 100% efficient. (A few other laws of thermodynamics also play in here)
A gas turbine has the advantage that it can use higher temperature gradients within, as well as high speeds and other mechanisms to take advantage of larger burnoffs of gas.
A gas turbine is 60% efficient at base load and largely will be able to maintain 60% efficiency while being maintained at this load. A gas oven has a rough efficiency of around 70-90 % in AFUE. AFUE does not measure actual thermal efficiency, you can usually subtract between 10-35% depending on your boiler system, which ends you between... 40-60% just like a gas turbine in a worst case. The better cases of 60-80% are unlikely to be a steady state efficiency and more likely to be achieved if you have a boiler with great heat capacity that can hold onto the heat for longer. The efficiency here is ruined by ignition each time the furnace has to start running.
Turns out you can't cheat thermodynamics, but you can certainly market like you did.
The reason is that simply a heat pump does not convert electrical to thermal energy, so it has no comparable efficiency in that process.
That's the definition of efficiency for home heating.
Furthermore, that 100% efficiency of a resistive heater is only true under very specific high school level circumstances. Under no practical circumstances (e.g. source resistance, reactive load) resistive heater is 100% efficient (though it can get close).
In cases of heating, resistive is 100% efficient as you loose none of the energy put in to waste heat, only effective heat, while a gas oven or heater will loose heat to it's exhaust gases, thereby being less efficient.
I wouldn't say this is "high school level" circumstances. The waste heat in the wires of your house feeding into the heater will also heat up, no?
The only energy lost is outside the system we're trying to measure, hence, not relevant.
The mains is normally AC. You WILL lose energy either in AC-DC converter or in reactive load of the heater.
Yes, reactive current is still current and any series active load (wiring) will experience that current and heat up. The reactive load itself is "imaginary".
Besides, for any reasonable heater arrangement, this loss will be negligible compared to any other heating mechanism.
Not the fact that conversion of electricity doesn't have make energy disappear.
Electrically powered heat pumps also produce >100% efficiency.
I am telling myself the same thing when I play videogames. :-)
And yeah that does seem to be "profitable". A 2070 Super card seems to net me a couple of bucks a day...enough to offset the cost. Probably not profitable in the true sense, but hey free heating is a win for personal finances.