A new generation of engineers has realized they can push heat pumps to the limit.
“New generation of engineers” is a bit cringe. The old generation knew thermodynamics pretty damn well. All that’s changed is they’re using R290 refrigerants and variable speed compressors now, but those don’t change anything from a physics perspective. COP is fun but it’s not even the right metric to use from a policy perspective, just like MPG. And despite being unitless, COP suffers from the same exagerative effect as MPG numbers. What matters is the carbon associated with delivering BTUs to a home, so here you can have the ridiculous case of delivering more BTUs at a higher carbon cost achieving a higher SCOP than the same exact heat pump delivering fewer BTUs at a lower total carbon cost achieving a lower SCOP for a better insulated home, and the person with the higher SCOP bragging about it like a clown. At least when the government tests COP it’s a standardized test so you can actually compared equipment (somewhat).
Regardless, nerds gonna nerd and no harm done (and I also track real time energy use of my heat pump, so I consider myself a nerd).
What really matters is the wattage needed to cool the space. That’s really it. The less energy used, the less the strain on the grid, or the less solar capacity needed.
Wattage is power, not energy. But I still generally prefer carbon as a metric because that’s the climate issue, so by focusing on it directly we can make more informed decisions. It also incorporates time of day/seasonal (peak) impacts implicitly, which also have profound effects on the grid, more than total energy used. The essence of our comments is the same though.
Be great if I could afford one though
Not sure where you’re located, but there are often significant incentives for heat pumps. If you’re US and low/moderate income, there are big programs ramping up via the IRA that will cover a large percentage of the costs, assuming you’re not in a total brain dead state.
Incentives are great for those who could afford it in the first place.
Can you not afford an air conditioner? A heatpump is only marginally more expensive
You can get window unit ac for under $200.
For under $500 one can get a window heat pump. (They are likely as shit as the $200 window A/C.)
I own one. It’s mounted in the wall not in a window but it’s a unit that can be used either way. We have central heat and A/C but our heat is a gas furnace. We have an addition that wasn’t on the central system and that’s why we have the wall unit heat pump/AC. It works pretty well as long as it isn’t bitter cold outside (-20 C/ -4F isn’t too rare). Also that addition has terrible insulation. (edit to add that the addition also has an ancient gas heater built into one of the walls but it hasn’t been used in decades. It has been tested though, it still works but it is scary.)
So I’m pretty happy with that heat pump and it is probably much more efficient than a space heater. But if I was really broke and just trying to survive a hot spell or a cold snap I’d more likely buy a $180 AC unit and a $20 space heater unfortunately.
Where? My $300 U shaped window AC is modern quiet, tidy and efficient, but I was reading about window heat pumps being $2-3k.
My wall mounted split systems were <$1000 AUD each, 3.5kw. Found a sparkie and a fridgie to do the install, set us back around $3000 for two systems installed.
Great units, added some wifi dongles and tied them into my home-assistant for remote / out of home control & scheduling.
Probably the best addition to our home currently, don’t know how we lived here using pedestal fans and gas heating.
Search Amazon for “window heat pump”.
I cannot comment on quality or efficiency.
Well all conventional air conditioners are strictly heat pumps, but when we say heat pump everyone usually means bi-directional heat pumps - ones that can provide heating as well as cooling. My Amazon results are not that and I was recently reading about them coming to market starting at $2k.
This one is $449 and clearly states several times it can heat with a heat pump.
Maybe it is full of shit. I cannot say.
Yes. I cannot afford an air conditioner. That was the post.
I’m just surprised there’s no “AI heat pumps” yet.
Now that’s something the world is really needed. (/s)
https://www.sciencedirect.com/science/article/pii/S2352484722012021
AI is the new rule 34.
Artificial intelligence (AI) models for refrigeration, heat pumps, and air conditioners have emerged in recent decades. The universal approximation accuracy and prediction performances of various AI structures like feedforward neural networks, radial basis function neural networks, adaptive neuro-fuzzy inference and recurrent neural networks are encouraging interest. … Thus, complex multi-objective problems that require high precision solutions to optimize the cost and performance of ideal RHVAC are solved using artificial intelligence techniques (Mohanraj et al., 2012).
Granted, this is modeling, not implementation, but.
I saw 5 for air-air and was impressed. Then I see SCOP? Oh please. Why not change the scale again to make sure nobody knows what a good value is. Just like SEER on an air conditioner.
SCOP varies depending on environmental conditions!
Real COP or go home IMO. Watts out/watts in, no fudging numbers to confuse consumers again.
Nice read
Define efficient.
