https://youtu.be/fxEqVuiHhM0

The more interesting graph is the total kWh saved per day (8:07). The colder it gets, the more energy he saves. That's because more heat needs to be pumped into the house, so a worse COP multiplied by more total heat equals more electricity savings (at least for the temperatures he's measured).

If he touches on them, it's briefly - if at all, e.g.:

- More expensive units, and more expensive to run power wise. It's always difficult to get adoption of new technology that's "better" but more expensive to buy & repair - to the point where RoI may never happen.

- Power grid implications during very low/record low temps e.g. shortages/blackouts, likely worse than those in summer if heat pump uptake is widespread.

- With a heat pump, you -need- an alternative source of heat - since some days when it's particularly cold, they just won't work, or work very inefficiently. Plus, if the power goes out... you're definitely not powering a whole house heat pump with a small generator like you could a natural gas furnace.

Edit: FWIW, I'd researched this topic heavily & seriously considered getting a heat pump to pair with a solar power setup. For a number of reasons (chief among them: no return on investment before the end of the heat pump's expected service life), I will not be getting a heat pump any time soon. That may change if prices drop dramatically, but that seems unlikely given their increased mechanical/electrical complexity.

> normal Americans

Please revise this phrase. America consists of many different climates and it's very unclear what you mean or why you chose the word "normal."

> More expensive to run power wise

You're comparing new gas HVAC vs new heat pump. However, don't forget about all the folks that are purchasing a heat pump to replace an existing gas unit! For example, my gas unit (Goodman unit used in California) is old and not even energy star compliant! A new heat pump will be more efficient.

> With a heat pump, you -need- an alternative source of heat

By 'you' are you referring to me (or, say, the ~7% of the US population that lives in my small area of the country)? If so, that's not true! It doesn't get too cold here. And I reckon there are quite a few areas in this country where it doesn't get cold enough for a heat pump to eat shit.

When you refer to prices and returns on investment, are you using a unit + professional installation cost (like $18k+ or something)? Or the unit itself (~$4.5k) plus perhaps a DIY installation costs (~$1.5-2k)? There is a big range there in costs, and the ROI is dependent on that.

My energy bills are 1/2 of what I was paying with an electric furnace last year.

In Seattle are highest usage months for electrical is in the winter, right when you will be maxing out that 50A breaker you had to install in order power that beast; check the notes from Mitsubishi, they are clear that it is not an efficient device in the range you suggest ( and seeing how in Seattle most homes are still at 100A service you must either be living in a newer home or one with an upgraded service ).

You realize that Seattle is now an importer of electricity and is no longer running surplus?

Or how about that the city has been using an unsustainable amount of water? ( i.e. where our power comes from ) Or that our electrical come at the expense of Salmon and the endangered Orca pod that lives in the Sound?

If you replaced your "furnace", which implies a central HVAC system, with a Mitsubishi Hyper-Heat, which I believe is only installed as a mini-split, what are you doing about your air quality?

The Seattle area suffers from "inversions" through out the year; a mini-split does nothing for air quality issues. The smoke that we dealt with in the fall? That wasn't even the worst air quality issue we have had in the last decade.

I am sure your electrical bills are 1/2 of what you were paying for an electric furnace, but unless you are abandoning the use of your heat pump for providing cooling your overall energy yearly costs are unlikely to go down.

I don't know situation, I don't know what options you had when you installed your unit, and I have not listed all of the good and bad that come with the unit that you installed.

There has been a lot of "mini-splits will save the environments" coming out of our City Council; there have been zero reports presented that back up those statements. The local heating and cooling people are happy to install units which have a higher markup/generate more work for them.

It's not a mini-split.

- Economies or scale will solve the repair and maintenance burden... hell, it's not like a gas boiler is maintenance free...fucking things requiring serving every year and break down all the time in the UK.

- almost noone has a generator when the power goes out anyway. This is a very wealthy American perspective.

- Gas boilers are far simpler units. Less moving parts, simpler electronics, all in all fewer points of failure than a cutting edge heat pump that can actually produce heat when it's below 20f (-7c, i.e. the only kind of heatpump that might stand a chance at heating throughout the cold winters most of the northern US gets).

- Be that as it may, heat pumps at this time are cost prohibitive - making them largely something only "wealthy Americans" can afford. Many people still run old 80% efficiency units because of similar reasons to boilers: they're cheaper, simpler, and less likely to fail.

My family has one in Poland, it was -20C this winter already and it worked absolutely fine. It's some cheap unit, wouldn't call it "cutting edge". I think there's a simple resistive heater that de-ices the fins at low temps, but it kept the interior of the house at a (very toasty) 24C pretty much non stop even in those low temperatures. I have no idea why people keep saying heat pumps don't work in low temps. I had a basic split unit fitted to my home in UK, literally a basic £600 midea unit and apparently it should work down to -25C without any problem.

>>Gas boilers are far simpler units. Less moving parts, simpler electronics

Have you ever looked inside a modern gas boiler??? I hard disagree that it has less parts than a modern heat pump. A heat pump is like your fridge - there's an inverter, compressor, and a whole bunch of fins, that's about it. A gas boiler has multiple tanks, burn chamber, exhaust recirculation, at least 5-6 probes to measure every part of the process(and they all can fail in surprising ways that renders your boiler dead).

A solution doesn't work in 100% of areas can still be the best one in the 95% of the places that do make sense!

And to your cost concerns, there's a bunch of Federal money (being deployed by the states) in the IRA to specifically pay for low-income Heat Pump upgrades.

If you can afford to have them just for cooling, you can afford to have them for heating as well; in fact, the capital cost may well be lower if people just used their air conditioning systems to heat as well.

The same goes for reliability - we manage to make air conditioning acceptably reliable and the tech is basically the same.

I've lived all around the US, and don't think I've ever lived anywhere with central air. Well, that's not quite true: in New Mexico I had a roof mounted swamp cooler, but that's evaporative cooling and not a heat pump. Elsewhere I've occasionally had and used a portable compressor unit, but rarely. I hadn't realized air conditioning was so overwhelmingly prevalent. Based on people I know and associate with, I would have guessed less than half that rate.

I was surprised when a colleague from Minnesota who moved to the south mentioned never having air conditioning. I'd expect that in many parts of Europe. And I've sweated it out while living there, but it's extremely rare in my experience in the United States.

I've always had central air, along with a gas fireplace for emergency heat which, thankfully, I've never had to use.

They range from sub-$1K single zone air-to-air wall/window units, to multizone split units, to ground source hydronic boiler/chillers that integrate with baseboard or radiant floors, which can get quite expensive to install, but that's at the high end. Generally speaking they're not really much more expensive than normal air conditioning. I've seen units that come in cooling-only and heating+cooling versions, and the cost difference is marginal (<10%) in those cases.

Some form of this comment always comes up in these heat pump threads, and I never understand the idea that heat pumps are some elite affectation that doesn't make sense for anyone else. Many millions of Americans live in parts of country where it gets warm enough in the summer to justify central air conditioning and chilly enough in the winter that you need heat but the heating source doesn't need to handle super low temps on a regular basis.

A heat pump is literally one of the simplest ways to address the year round climate control needs for those people since it's a single system that handles both heating and cooling with only marginally more complexity than the air conditioner you'd want anyways. Throw in electric backup heat, which is probably the simplest backup and keeps the system all-electric, and you have a system able to handle a pretty broad range of temperatures all year. As heat pump technology gets better, the applicable temperature range gets colder and colder and makes heat pumps practical for a wider range of "normal Americans".

This isn't just theoretical. Heat pumps account for 17% of heating systems in the US, which isn't huge, but over 40% in North Carolina, South Carolina, and Alabama and a significant percentage in many other states as well. Obviously there are cases where heat pumps are at least currently impractical given the construction, climate, etc, but dismissing them as some effete toy seems a bit silly.

Edit: Interestingly, most states seem to have a significantly higher percentage of homes with electricity as their primary heating fuel than they do homes with heat pumps, suggesting a lot of homes with things like electric baseboard heating. While not all of those homes necessarily have central AC, using Georgia as an example, 85% of homes have central AC and 53% use electricity as their main heating fuel, while only 29% have heat pumps. That suggests quite a few homes with central AC that use electric baseboard or similar. Heat pumps for those homes seem like they'd be very practical.

Modern heat pumps redirect some heat to prevent the coils from freezing. What you wrote is common FUD pushed by the oil & gas companies.

That said, you'd be a fool to live in an area with life-threateningly low temperatures and not have a backup heat source.

It's not FUD, and you COMPLETELY ignored & omitted the rest of my sentence from your quote. I'm well versed on how heat pumps work. I was not saying heat pumps don't work below freezing. Rather than simply repeat myself, let me rephrase:

1. Heat pump efficiency gets worse the closer you are to the minimum (outside) temperature they're rated down to.

2. Even with the best (and most expensive) technology, that means efficiency of these units approaches that of a $15 space heater.

3. When it gets TOO cold, they can stop working entirely if they don't have a resistive backup heat system (which, again, is effectively a $15 space heater you paid a lot more for).

Both Canada & the northern US experience these temperatures occasionally (-10f to -30f and worse on some occasions).

Hence the need for backup heat - e.g., a pellet or wood-burning stove, backup furnace running propane or natural gas, or even just something cheap and simple like a $150 portable diesel heater. You don't want to be left without heat in a multi-day power outage after a half inch of ice and high winds.

For backup heat, it's more efficient to burn whatever fuel for heat than run a generator outside to power space heaters or a heat pump at those brutally low temps that often follow those hard ice storms.

What part of redirect is confusing?

In the installs I've seen they did it from inside the house i.e. literally cooled the house down.

Cooled the house down, or simply warmed it less than would be possible otherwise, assuming that magic prevented freezing of the coils?

I'll take a reduction in efficiency over a complete lack of function.

Your whole argument is. Heat pumps need a secondary heat source because at the temperatures around 0C they accumulate ice on the heat exchanger outside. To melt the ice they reverse the energy flow so they cool the house and heat that heat exchanger. You asserted that it's just FUD and they can "redirect some heat" instead. This implies they don't cool inside and instead redirect heat from elsewhere (second outside heat exchanger perhaps?).

But it appears there is no second heat exchanger outside and the modern heat pumps work just like heat pumps from couple years ago.

As for keeping the functionality - it's a philosophical question. For me personally, if I turned on the heater because it's cold inside and it started blasting cold air, I'd call the repair people immediately. While it still works in the sense that it makes noise and consumes energy, it stopped performing its function of heating so I'd consider it lost the functionality I am interested in the most.

It's only a -need- in certain locations. The one I have claims to be fine down to -5 degrees. There is zero chance we will get anywhere close to that in my lifetime. Heck, even getting down to 32 is incredibly rare. So we are fine without an alternative source of heat.

As for other points, we have never had a power loss/blackout in the nearly 3 decades we have lived here. And electric is cheaper than gas due to nearby hydroelectric dams.