Heat pumps, heat pumps, heat pumps | Hacker News Reader

Heat pumps, heat pumps, heat pumps

noahpinion.blog

26 pointsjseliger111 comments

The first part of this article is a good intro to how they work. But still, one flaw.

I'm guessing that a lot of people are simply not aware that compressing a gas will heat it and decompressing it will cool it - at least not to any significant degree. So (imho) please talk about how the operation of an A/C makes this fact obvious - make an appeal to everyday experience. And THEN talk about how putting it in reverse makes a heater, even when it's really damned cold outdoors.

You probably already know this, but for anyone else reading - it's more than just compressing and decompressing - it's changing phase between liquid and solid!

It takes a lot of extra energy to go from a liquid to a gas - think about how when boiling water, it doesn't all immediately turn into steam when it hits 100 degrees. It takes a long time to boil it down to nothing, even on a really hot stove. That's because switching from liquid to gas takes more energy than just getting hotter.

The refrigerants used in ACs and heat pumps take advantage of this behavior to maximize how much heat they can move - much more than if they stayed as a gas

Good point. I kinda skipped over the phase change part of the story.

This too can be used explain the heat pump concept better. Freezing or boiling water takes time because it takes energy.

I really wish I could buy a miniature heat pump to blow cold air on my body or face instead of cooling my entire room.

Obviously there would be 2 units, one inside and one outside, but mobile AC units are way too big, consume too much power, and suck hot air from outside which is quite inefficient (the physics are simple, a mobile AC units ejects hot air outside, so air must enter the room somehow).

I hope it would be possible to have a small, simpler heat pump that use something else than a refrigerant gas, maybe co2.

I could buy the cheapest fridge and make one, but I can't extend the range of the gaz pipe.

It doesn't necessarily eject hot air outside, right? It just "ejects" heat outside. It could easily have two tubes or something, sucking in warm air from the outside, heating it up, and ejecting it outside again. However, since you have to create a (temporary) opening to put part of the mobile ac outside, warm air will still get in.

You could just use a fan to blow air over water onto your body. The evaporation will cool it down a little.

The cheap one units AC on wheels do eject hot air outside.

At least in europe we don't have the window AC units, we have either split or single unit on wheels.

They're not cheap, but they exist.

https://www.coolmitt.com/

Michael Liebherr, who runs the cleaning up podcast series and is a British Conservative politician as well as the founder of the Bloomberg Clean Energy fund, has been calling up electrified heating and industrial heating as the next trillion dollar investment opportunity. The solution there is mainly going to be switching from burning stuff to using heat pumps and other solutions. The reason the opportunity is so large is that there is a huge potential for cost savings there.

Heatpumps can deliver 3x or more energy back for every unit of energy you put in. Contrary to the popular belief there are almost no industrial heat applications that can't be electrified. The majority is rather easy and involves applications that require heat in the lower hundreds of degrees celsius. Easy. Heatpumps can do that. All you need is a good source of temperature gradient and electricity. You can go much higher than that with resistive heating, plasma heating, inductive heating, etc. It's just a matter of applying enough power to these things.

You eliminate a lot of emissions, supply issues and other logistics by doing so. That's where the cost savings are going to be.

I highly recommend heat pump water heaters if they fit your use case. Mine cost $650 after rebates and dropped my annual electrical usage by ~$400. They have some quirks. There is a condensate line that needs to constantly drain. Also, they pull heat from the air, so it is usually best to have them outside of conditioned spaces. You can also duct them however you like. All that being said, I installed mine in under a day.

I just ordered a Rheem Proterra and am excited to give it a try!

And in some states in New England and the Pacific Northwest, there are a substantial number of households that still don’t even have AC, which reduces the savings from heat pumps.

The percentage of households without A/C in California is even higher than Oregon. 28% vs 24%.

The states with the highest percentage are Alaska at 93%, Washington at 47%, and Hawaii at 43%.

Data from:

https://www.eia.gov/consumption/residential/data/2020/state/...

The one thing that is missing from this article is that heat pumps can only create a certain temperature difference (while remaining efficient). In Europe, most houses are heated by pumping hot water through radiators (as opposed to blowing hot air around). Heatpumps can typically only heat that water up to 30 to 40 degrees Celsius while remaining efficient, which is not enough to heat the old, badly insulated houses in Europe. They need to renovate houses first, insulate them and replace the radiators.

For Condensing boilers, the temperature of the water coming back from the radiators needs to be 45C in order to hit the advertised efficiency and eponymous "condensing", this is why their real measured efficiency is more like 75-85% than 96+%

Same fix, larger, double vaned radiators and better insulation which is why some people are pleasantly surprised they don't need to switch radiators when moving from a modern condensing boiler setup.

The biggest problem I see, as someone who has tried to get a heat pump installed in both residential and commercial settings, is that the trades are very, very slow to change. They have, by and large, built their careers on burning natural gas and are not willing to entertain the idea that it isn’t necessary, particularly where the new product requires less maintenance which is their bread and butter. It will change, but oh so slowly.

> Heat pumps heat your house much more cheaply than other types of heating, since they’re incredibly energy-efficient. So you can save money.

Yes, but no. Heat pumps are more efficient but generally natural gas prices are much lower than electricity prices for consumers.

I should be able to save money because my utility should incentivize me to be more energy efficient and help offset the cost but they don't.

It strongly depends on the country you live in. But generally we can hope that gas is going to be more expensive than electricity in the future.

no. We can hope that electricity becomes a lot cheaper than gas. a distinct difference.

your phrase would mean that they just make gas more expensive, and overall heating costs just rise

we should have had an abundance of electricity by now, but nuclear disasters in US, EU and JPN have really slowed that upwards trend of power source to a crawl

Nuclear is way more expensive than wind or solar power so nuclear will not play any part in reducing electricity prices.

Nuclear has the large advantage of being available at those cold quiet winter nights when the temperature drops below what is considered pleasant and you'd like to warm your home. Solar does not work come wintertime here in the north, wind sometimes works but often does not. If your country has the geography to allow for hydroelectric plants those are a good option which can even be used to store excess power from solar and wind, otherwise nuclear is one of the few dependable sources which do not rely on fossil fuels. Geothermal is another but that is even more geographically limited than hydroelectric.

For me, this was not just about cost but principally about getting of natural gas.

But regardless, it also made financial sense with the prices here in the Netherlands, in the long run. It was quite an investment, but it should pay off in the end. A m3 of gas here cost (when I did the calculation in February 2022) about €1.78. That has gone up and down since then. A m3 of gas contains about 9~10 kWh of energy. Let's say 9 kWh comes out via my heated floors. That's ~€0.20/kWh. At that time, a kWh of electricity here cost about €0.39/kWh. That's double the price per kWh, if I don't take the Coefficient of Performance of our heat pump into account, which multiplies the energy output by 3 (even at -7 Celcius) to 5, depending on conditions.

And I have not yet taken into account here that the energy from my solar panels is cheaper than buying it from the grid.

At the moment, prices are better (install was in March after a year-long wait) and in the meanwhile also got a dynamic energy tariff with lower prices on average, so the comparison is harder to make ATM. We haven't had both a for a full winter yet, so we'll see.

Pardon me for being out of the loop (I am not yet a homeowner and things like this are beyond me for the moment):

Is there a reason heat pumps are now more relevant? Has there been a technological innovation here? Is this new technology? (I'm asking this genuinely - not with snark).

I feel like I've read/heard about heat pumps a lot more recently and I'm wondering why. Many thanks in advance!

Heat pumps exist for quite a while. The reason ypu hear about them is climate change, all alternatives, from gas to oil, burn fussil fuels. That discussion was pushed by the war in Ukraine and, lately, a highly populized, and polarized, debate in Germany. The only alternative being equally good for the climate is using excess heat from industrial plants, e.g. those burning garbage. Up to know, at least in Germany, gas was just unbeatably cheap for heating houses. That's gonna change.

Fossil fuels should not be used to create heat anymore due to climate change. People are becoming more aware of that currently (especially in Europe) which is why heatpumps are a hot topic.

Thinking of it, heat pumps have one added benefit: energy storage. Heating is using water reservoirs, one for hot water and one for heating of the building. This hot water can be produced whenever you want, those reservoirs hold temperature quite well. A lot of heat pumps can use excess renewables, and store that energy in the for heat. Heat that is needed as heat anyways.

Yes, heat storage is a bit simpler than electricity storage so it can be used that way. In Europe, the power grid operators can often remotely shut down your heatpump (if you have opted into this in exchange for a cheaper electricity price) so you have to store 1-2 hours of heat.

Our gas system is producing hot water twice per day, scheduled, and heat three times, also scheduled. Having those time windows, partially, remote controlled would be already now totally doable and we wouldn't see any difference in real life.

Two reasons. One, yes they have gotten more efficient, and depending on your local climate, are now possibly the most efficient method for heating your home.

Two, the switch to renewable energy is resulting in a push for the “electrification of everything”. Getting home appliances that previously burned fossil fuels onto the electric grid enables emissions-free methods of power generation to be used in the future, even if they are not in use yet.

And even with fossil-fuel burning power plants, they have an economy of scale much greater than the furnace in your home. So using electricity generated at a fossil-fuel burning power plant to power your heat pump will still result in less emissions than burning that fuel for heat directly in your home.

The big one is that we need to decarbonize building heating and cooling as soon as we possibly can (like, by 2030) in order to avoid disastrous climate scenarios. Heat pumps run off electricity, which is starting to be decarbonized rapidly, and heat pumps are also battle-tested solutions that many countries already use so they are the main technology to get off coal, oil, gas, etc for cooling and heating.

Last year, the US passed the Inflation Reduction Act which created a ton of consumer and industry incentives to manufacture and deploy heat pumps, which created a lot of interest. Additionally, Russia's war in Ukraine made it clear to many countries that they didn't want their energy security dependent on an aggressive nation, so lots of European nations rallied to install heat pumps amid a possible gas shortage from Russia.

One cool thing about heat pumps is that they run more than 100% efficient. This is because they move energy around instead of generating it. Working in good conditions, most units these days will run around 300% efficient. It really depends on your specific home, electricity prices, region, etc whether this efficiency results in savings on bills, though. Many older generation heat pumps didn't work as well in colder climates, but now that's not as much of an issue. I believe I saw that one of the US states with the fastest recent heat pump adoption is Maine, and Norway has a very high heat pump adoption as well.

I am also surprised why they are suddenly everywhere, when most A/C brands installed in Europe (including mine) already have heat pumps built-in. What I am missing?

> Maybe a heat pump is just too boring and simple to have a culture war about.

As a German, I can confidently reject that hypothesis...

Related, we recently put in a hot water heater with a heat pump. It blows cold air exhaust, so it keeps our basement nice and cool. It has worked well and reduced our power bill slightly.

Am I the only one having DNS issues with this site? For some reason, no matter which DNS server I query, it resolves to my router, yet it seems most everyone reaches it without issue.

Here is how I try to get people enthusiastic about heat pumps: we need some really big heat pumps for some really big space habitats.

> Our £25,000 heat pumps left us out of pocket. Brits who signed up for boiler upgrade scheme are left facing £5,000 energy bills, wake up to cold homes and have to use blankets to keep warm

https://www.dailymail.co.uk/news/article-11972635/Britons-co...

Whats that supposed to tell us? That someone didn't understand heat pumps, put a wrongly sized heatpump into a wrongly equipped house and now the owners are complaining?

> they take up less space than a normal heater plus normal AC.

Don't you still need a normal heater for hot water?

Why shouldn't you use the heat pump to heat water?

Do they make heat pumps that do both air and water in one unit? I haven’t seen this.

In Europe, houses are heated using warm water so its the same. Also, many heat pumps store heat in a warm water buffer. You can use a heat exchanger to heat water with it. The american way of heating the house by blowing hot air around isn't the most efficient as air doesn't transport energy very well.

Aren't heat pumps the same as air conditioning? I have one

> Aren't heat pumps the same as air conditioning? I have one

not even remotely

I ma fairly sure that in europe A/C and heat pumps are the same (cooling/heating)

Then you are incorrect

That’s a stretch.

Do explain

They’re actually nearly identical in concept.

An air conditioner is actually just a one-way heat pump. The major difference is heat pumps can run in reverse.

Actually an AC unit is a heat pump, just a one directional one that moves the heat outside.

It depends. Window or floor units that are portable are not usually heat pumps. They use a different cycle with the refrigerant. Ductless splits and central air are often heat pumps.

How so? Anything using vapor compression refrigeration should technically qualify as a heat pump. They may not move the heat as far, but that shouldn't matter. A swamp cooler isn't a heat pump, but the units you describe would seem to me to obviously qualify.

You can buy portable window heat pumps from several companies. They’ve been around for a while.

Sure, there might be some in some markets, but when I go to the store around here practically none of them are heat pumps. They're rare to find shopping around for some reason.

Like, look at this list. How many will heat? Probably none.

https://www.lowes.com/pl/Window-air-conditioners-Room-air-co...

I can walk into a dozen stores selling window AC units around me with hundreds in stock ready to go today. If I want one with heat near me, I'll have to custom order online. Thus, the vast majority of window AC units you'll encounter in most of the US are cooling-only unless the person knew they could order one which does heat from someplace else online.

Home Depot seems to carry the LG window heat pumps in stores.

I do agree that it’s odd that most units can’t heat and that the heat pumps are so poorly advertised.

> They use a different cycle with the refrigerant.

No, every major consumer air conditioner and every major consumer heat pump on the market that I'm aware of uses the same cycle (the vapor compression cycle). The only difference between a vapor compression cycle AC and a vapor compression cycle heat pump is which of the two loops is being used as a heat sink and which as a heat source. You could in theory do this by simply reversing the flow direction in the refrigerant loop, but in practice the better approach is to do the same thing with valves, allowing the compressor to always operate with the same flow direction.

It's important to distinguish between the heat pump itself and the heat exchange medium used to transport that heat into a given space though. If you try to connect a heat pump meant to replace a radiator system in an old (or european) dwelling, the radiators we're really designed for cooling, and you may have performance issues. But that has nothing to do with the heat pump itself.

> When it’s cooling your house, it’s just a normal AC. But did you ever think “When it’s cold outside, why can’t we just turn the AC around and air-condition the outside, so it heats up inside?” Well, it turns out you can! And that is how a heat pump works. It just moves heat from the outside of your house to the inside, just by turning the air conditioning in reverse.

That's what most air-conditioning does in europe, it is also used for heating

Probably location dependant but numerically I'd guess most ACs that Europeans have interacted with are in cars, which only very recently started using heat pumps for heat in the EV era.

That dpends where you are in EUrope. Lots of housing have AC in the Mediterranean countries, and even in the famously AC-deficient UK pretty much every office building and supermarket will have AC.

I wouldn't say most air-conditioning in Europe includes heat pump heating, in fact for most of Europe I'd say its not super common.

Germany is in Europe. Only 4% of residential heating is from electrical sources, which is both heat pumps and resistive heat. 51% of household heating is from natural gas, 20% is from heating oil, and 18% is from district heating.

https://www.statista.com/statistics/1189752/household-heatin...

Here's iea's residential heating sources in 2020. Italy (also in Europe) sourced 60% of its energy for residential heating from gas. Hover over electricity and see how low of a percentage it is in most countries.

https://www.iea.org/data-and-statistics/charts/proportion-of...

They’re the same core concept. There are generally two major differences:

* a heat pump has a switch valve for coolant. This allows it to move heat in either direction.

* while not strictly necessary, heat pumps typically have a variable rate compressor. They scale to match load.

Some heat pumps will also have a supplemental electric heat element when conditions are extremely cold.

This feels like a US vs rest-of-the-world thing. In the US, “central” air conditioning is usually one-way and paired with a furnace for the winter. The main alternative is window ac-only units which are removed in the winter.

Mini-split heat pump units that heat and cool are everywhere in Asia and parts of Europe but are still relatively uncommon in most of the US. I installed one last year and had to shop around for an installer, several of which tried to talk me out of it. If this is what you think of as “air conditioning” then you’re right. Most Americans would think of a central air system that cannot heat.

Minisplits are becoming very common in the older cities - NYC, Boston - where they're much easier to retrofit into plaster-and-lathe walls.

In regions like the Southwestern US, where furnaces are not needed, AC units are heat pumps. The US is large enough to defy most generalizations.

Yep, most people have "heat pumps" already .. in their car or refrigerator ;)

any idea about what secondary technology to invest in in anticipation of heat pumps catching on?

Installer networks with installers that understand the technology rather than try to talk customers out of it.

Nuclear, nuclear, nuclear.

You can't fix global energy problems by raising everyone's HVAC coefficient of power to 4.

One of the most amazing triumphs/failures of capitalism, is the ability to fend off competitors with even a mildly long payback period for decades.

It boggles my mind that modern democracies like Germany or the UK could have ignored heat pumps for so long.

Because it isn't mildly long. It's either very long or infinite, anywhere where gas is ~ 1/3 the cost of electricity per kWh. COP of 3 at a 3:1 price ratio for electricity to gas = 1.

Which itself makes sense if you use gas as the RELIABLE source of kWh. You need to burn ~ 3kWh of primary energy in gas to deliver 1 kWh to the household, so 3:1 makes sense, and the RELIABLE source of kWh is the price setter because a failure of the grid is literally an existential crisis, something the "agile" private sector companies aren't liable for.

An auxiliary annoyance in the UK is that reversible pumps aren't renewable for government grants. This is ostensibly to discourage aircon, but rather silly, since there are few easier green power problems today than "satisfy a demand that is almost perfectly correlated with high insolation".

FYI as a type the largest suppliers are gas, solar, then nuclear - of which nearly half is being pulled from France, an amount that for some reason isn't always counted by some people.

> you need to burn ~3kWh of primary energy in gas to deliver 1 kWh to the household

Is that so? I thought electric generation from natural gas was at least 80% efficient - and transmission losses maybe can pull that as far down as 66% - but not down to 1/3.

I think they are referring to the COP of a heat pump as at least 3, whereas natural gas appliances by definition must be below 1.

In many EU countries that cost difference is a policy failure:

> Italy, Spain, the United Kingdom, Belgium and Germany. All five countries overtax electricity — in three cases by more than 200% — and undertax oil and fossil gas while not taxing wood use at all. Only in Italy is the tax rate on heating oil close to the value of the environmental costs caused by its use.

https://www.raponline.org/knowledge-center/aligning-heating-...

But going from first principles Renewable Energy Without the Hot Air could run the numbers back when it was written in 2008 and show this was a good move: https://www.withouthotair.com/c21/page_151.shtml

> Let me spell this out. Heat pumps are superior in efficiency to condensing boilers, even if the heat pumps are powered by electricity from a power station burning natural gas.

A large percentage of homes in the UK are not and cannot reasonably be insulated well enough for heat pumps to work.

I don't quite understand why I can't just run a heat pump 2-3x more powerful, but apparently that's not the done thing.

Can you elaborate on the insulation part? My understanding is that if you have a poorly insulated house you just need more heat energy to keep it warm, I.e. a larger heat pump.

That's my logical understanding as well. I'm wondering whether it just ends up being significantly more expensive than gas heating so no-one talks about it.

> it just ends up being significantly more expensive than gas heating

Bingo.

A heat pump is much more effective if you only have a small temperature difference [0]. If your house is well insulated and you have underfloor heating, you can heat your house with 40°C (sorry for European units) water to keep it warm inside. If you have poor insulation and small heating elements, you need much hotter water (>60°C).

A heat pump can have a carnot efficiency (theoretically achievable efficiency) of >10 to warm water from 20 to 40 degrees, but only ~5 if you have to heat it from 20 to 60 degrees (not sure about the numbers, but you get the idea).

[0]: https://energyeducation.ca/encyclopedia/Carnot_efficiency

The problem lies in the radiators. Heat pumps can not "lift" the temperature more than 30-40 degrees Celsius without getting inefficient. So at -5°C outside, you can only warm water up to 35°C. At this temperature, your old radiator doesn't transfer enough energy from the 35°C warm water to the 20°C room. You would need to either heavily insulate your house or replace the radiators.

This would be more convincing a reason if the new builds over the last couple of decades had been fitted with good insulation and heat pumps.

Since they dragged their heels on that low hanging fruit, I'll suggest they've not really even tried to make it work elsewhere.

(There have been some improvements so I don't want to get carried away, but there's also estimates of many Billions wasted by not doing what was obviously a good idea at the time).

Also, recent real world experience suggests more older buildings than you think will work. Britain doesn't get that cold for that long and modern heatpumps and insulation techniques are pretty good.

One of the issues with heat pumps is that there are very bulky and may require big installation work.

The alternative being what?

No heat pump?

IMHO, the main reason heat pumps are pushed is that most countries are having big issues with their electricity production and grids. Indeed, the move away from ICE cars and gas at home means electricity production is struggling. Cynically: "Look we don't need to invest we can just tell people to install heat pumps".

Here in the UK for many properties heat pumps are either very expensive to install or they destroy the small garden/patio people have, or both so I can see people trying their best to avoid them, quite reasonably so because there are not well suited.

I don’t follow your logic at all. Sorry.

Huh? The main reason heat pumps are being pushed is because they are extremely efficient, not as some kind of sacrifice that we are doing to protect the grid. There is no better option if we are moving away from gas at home.

The only competitive alternative is gas powered heating. However, I believe it’s more energy efficient to use natural gas for electricity generation and use heat pumps for heating rather than piping gas to people’s homes and burning it there. The exception is when it’s so cold that heat pumps do not perform well (although modern heat pumps can work in very cold situations)

The exception is for old housing stock which isn't well enough insulated to be heated by a heat pump, and there's huge amounts of single glazed, poorly insulated (by modern standards) housing around in the UK

Doesn't that lack of insulation affect all heating and cooling technologies? Seems kind of orthogonal to me. Where insulation is poor, people - individually and/or through the government - absolutely should be investing first on improving it. But once that's done, we're back to the original question of what technology to use for heating or cooling the now-well-insulated space. Note that it's entirely possible e.g. for a furnace to have a greater capacity to heat a space while still being less efficient at it within any but the most extreme ranges.

Invest in what instead of heat pumps? It's hard to understand what you're pushing for. Resistive electric heat (which would be less efficient and have a higher load on the grid, and your power bill too)? Non electrical heating (fossil fuels)?

In the US there isn't a concerted push to disinvest in the grid for the heat pump lobby's sake. Our grid is old and frail and Texas is insane and California has way too much solar and not enough storage, but heat pumps aren't really a major factor there.

And overall, isn't higher efficiency good for everyone (for costs, climate, noise) even if we do upgrade power grids and production? It shouldn't be an either/or but both.

Invest in the grid and electricity production so that the many people for whom heat pumps are not a practical option have an affordable solution.

France used to push for all electric at home, with resistive electric heat because they had plenty of affordable electricity. I'm sure it's the same in countries with plenty of hydro.

Now, here in the UK the grid is already maxed out. Renewable projects cannot go forward because they cannot connect to the grid. So the government is desperate, taking into account the bloodbath that's coming with EVs and that they want us to get rid of our gas boilers as well. Heat pumps minimise impact on grid and push a lot of the cost to people.

I'm not saying that heat pumps should not be installed where a good fit, but in the real world there aren't in many situations and for many families's budgets. It's never black and white.

> Now, here in the UK the grid is already maxed out.

A maxed-out grid is an argument in favor of heat pumps, since they're more efficient than resistive - especially at the temperatures that prevail in the UK.

Yes, except that they are impractical and unaffordable for many, and that the grid just be upgraded anyway (EVs, etc), as I wrote in all my comments.

I am just saying that heat pumps are no panacea and are not always a practical/viable option so let's not create another sacred cow here.

> they are impractical and unaffordable for many

If you're not going to provide any evidence, please stop making that claim. Heat pumps are not bulkier, noisier, or more expensive than any alternative that would suffice for most people. They are more efficient and environmentally benign, likewise. Using dogwhistles like "sacred cow" or insulting interlocutors is not going to carry the day for you.

Please be civil or "have a good day".

Please take your own advice. Your reliance on fallacies, falsehoods, and repetition is toxic to civil discourse, and that's before we even get to the explicit accusation that everyone who disagrees with you has tunnel vision. Tone policing never works when it comes from the worst offender.

Funny you mention Texas, as these days 60% of Texans currently heat their homes from electric (almost always resistive) sources. If we shifted all of those resistive heaters to heat pumps we would net reduce our electrical demand in the winter.

https://www.statista.com/statistics/1231906/residential-heat...

Sorry I wasn't specific enough. I meant Texas's private, less regulated grid and the issues stemming from that: https://en.wikipedia.org/wiki/2021_Texas_power_crisis#%3A%7E...

It's just funny that in the same country, two states suffer similar electrical outcomes despite polar opposite politics. Californians went all in on solar and their heavy regulated utility couldn't keep up, causing rolling blackouts and bankruptcies. Texas took a no shits given approach to their electric market and that backfired too, skyrocketing prices and killing hundreds.

I wonder how other countries deal with their grid upgrades. Judging by the GP's points, maybe not very well either?

> skyrocketing prices

I just signed a contract a few days ago for 100% renewable $0.10/kWh including delivery for another year after coming off a 3-year contract for $0.08/kWh delivered. I don't know that I agree with "skyrocketing prices". Prices did increase the last couple of years with natural gas prices generally going sky high (I was seeing contracts ~$0.14-16/kWh for comparison), but prices have fallen again back to levels they were pre-Ukraine and pre-deep-freeze. Given most other things have inflated a good bit, real electricity prices in Texas are actually down compared to a few years ago.

I wouldn't consider $0.10/kWh a "skyrocketing price". Average electricity prices in EU are supposedly €0.25/kWh which is what $0.27? 10 / 27 = .37, so my sky high electricity prices are a third of the average rate in Europe, so I guess theirs are considered astronomical? What are you paying for your electricity?

https://ec.europa.eu/eurostat/statistics-explained/index.php...

Had the majority of resistive heating sources converted to heat pumps before the deep freeze, it possibly wouldn't have happened as it would have greatly reduced the electricity demand. Also, if things like gas compressors and other gas infrastructure was properly tagged as critical infrastructure Texas wouldn't have shot itself in the foot turning off those circuits causing cascading gas power plaint failures.

The skyrocketing during the freeze, I mean, because of supply and demand. And to your point, 10 cents is pretty low. California is up to what, 29 cents a kWh? I pay around 12 in Oregon, 6 in Chicago before that thanks to nuclear.

> The skyrocketing during the freeze, I mean

I paid $0.08/kWh during the freeze. Very, very, very few people were on spot pricing plans. Like maybe a few thousand out of 10 million households. Griddy had a peak of 29,000 customers. They were urging customers to leave like a week or more before the freeze, so chances are they weren't still at 29,000. Even then, that's like 0.2% of households in Texas.

That's good to know. The media painted a very different picture. I should've known better :)

Don't get me wrong, there's still some amount of concerns about some of these charges. There are a lot of complicated things going on there, a number of court cases, and there's definitely a mixture of things going on. I was buying electricity through a retail electric provider (REP) who ended up folding and selling my contract to a new REP after the freeze so I and everyone else with a fixed contract in the deregulated areas had practically zero impact, maybe slightly higher delivery charges. Other people are on co-ops, and they might have to have some extra payments in their bills spread over a few years to cover the costs (depending on some court cases) or have their co-ops get pretty heavily restructured. Then there are some municipal electric companies who were often mixed, as sometimes those had generating capacity (so if those stayed online they received these huge payments or balanced out) and sometimes they didn't.

But those people showing their $20,000 home electric bills? Far outliers, way outside the norm. They had signed up specifically for spot price energy plans without realizing what that really meant. I do imagine a number of people probably really didn't understand their plans, as its really easy to change plans and Griddy did a lot of direct selling.

https://www.texastribune.org/2023/03/17/puc-appeals-court-ur...

For a lot of people though there was confusion related to energy prices increasing after the freeze, which was correlated but not necessarily caused from the freeze. Global gas prices shot sky high, a lot of LNG capacity was added for export, a huge amount of Texas electricity is from gas, so electricity prices increased around that same time. Not necessarily from the freeze though, but most people weren't paying attention to the natural gas prices.

Thanks for this detailed explanation!

> No heat pump?

In places with mild climates, you might not need anything at all. If you're in a place where it gets hot, a heat pump is practically an exact drop-in replacement for an A/C unit except that it provides heat as well. In my area, you basically can't even buy a one-way A/C unit any more because it's so obviously inferior. If you're in a place where it doesn't get hot (or you've decided to forego cooling in summer), a heat pump is no more expensive, bulky, or noisy than a boiler/furnace setup. Some people don't notice because the old tech came with their house, but that doesn't make it actually good. Again, where I am gas/oil heating is "grandfathered in" for existing homes but forbidden for new construction. The only real competitor to heat pumps is resistive electric. That's cheap and easy to install, and quiet, but considerably less efficient (and does nothing for cooling).

"I don't need/want what a heat pump provides" is not a particularly compelling point when most people do, and even the people who say that often change their tune when they try to sell their now-considered-deficient house.

Most people here in the UK don't find heat pumps practical or affordable.

Again, nothing is black and white.. and commenters here seem to sugger tunnel vision syndrome.

Bulky how? The mini splits are pretty small and you just pipe through a small hole in the wall.

Ground-based ones are extremely expensive and require excavation work. Not a practical or affordable option for most (maybe unit is bulky as well but I don't know).

Air-based ones are quite bulky when you consider many people in the UK live in small houses or terraced houses where having to install the unit means they pretty much lose a lot of their yard, and they are still expensive.

The problem is that everything quickly becomes a sacred cow these days. Heat pumps are one these days. They may make sense in some situation but they also don't in others.

Some countries had been pushing for all electric at home for a long time, e.g. France. No heat pumps but plenty of affordable electricity off the grid (which also works equally well in a house or a flat). So why the change? Again the reality is that this is because of general issues with production and/or grids with investments lacking.

Frankly, from a British perspective, telling people to install heat pumps at the moment is a bit of a "let them eat cake" approach.

None of what you've said is true. It's trivial to mount heat pumps to a wall - they're fairly light.

I recently did it on the outside of my brick apartment in NYC. No special equipment needed.

I take this to mean that in the UK there is some sort of government propaganda pushing for mass heat pump adoption? How interesting.

In the US it seems like a bottoms up effort, where homeowners and small businesses are gradually learning shout the benefits of heat pumps (especially air sourced mini splits) and voluntarily upgrading to them. Though in some states, energy efficiency rebates and new building codes do encourage them (especially for those communities targeting net zero).

You're right though that it's not right for every situation. Renters, for example, often have to live with resistive electric space heaters if the apartment has insufficient heating.

Mini split could be even smaller if you want to cool down a small room.

They could even be portable and/or just blow fresh air directly on the person instead of cooling an entire room.

Heat pumps consumes a lot of energy and have too much cooling power. I would live a fine life with an air around 23 or 25 celsius.

25 C? Lol, that's way hotter than I turn the HEAT up to in the dead of the winter cold. Isn't that tremendously uncomfortable..?

Anything above 19 C or so and I start to melt. I'm impressed by your ability to shed heat!

It's sensible to use AC to only bring temperature down to warm instead of freezing cold like they tend to do in the US, especially since you're probably already lightly dressed. Setting it to 23-25 does sound like a good compromise, also implying that AC stays off until temp reaches above 25C (also sensible, IMHO).

Actually here in the UK we're having a bit of a heat wave and it's currently 27C inside my house downstairs and hotter upstairs.

A gas furnace and AC combo is not smaller.

I really want to make my miniature AC system using a fridge heat pump.

Problem is to fill it with refrigerant gas.

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