A heat pump just makes no sense whatsoever for me in my northeast town. The electric bill alone would outpace the old propane bill, not to mention installation.
And it won't even work during some of the coldest winter weeks when you _really_ need it to work.
Maybe I would consider it if I was in, like, Nevada or somewhere.
The notion that heat pumps don’t work at low temperatures hasn’t been true for years. I think you may be surprised to find that just about any heat pump you look at has good efficiency down to very low temperatures.
That’s true, but still doesn’t always make heat pumps the most cost effective choice to operate. For example, last winter I paid an average of $0.24/kWh for electricity vs $0.05/kWh for natural gas. Even if a heat pump had a perfect 4.0 COP all winter, gas would be ~15% cheaper. Electricity prices really need to come down before it will be viable for everyone.
Does your 0.05/kWh include the distribution costs? The thing to do once you go to heating with gas is to just switch completely to electricity and turn off gas. In my experience (admittedly not in the US, but several other countries) distribution cost often more than double the $/kWh for natural gas (especially if you only heat part of the year).
This varies quite a bit based on location for instance here in Florida natural gas is $0.13/kWh while electricity is about $0.12/kWh, also where I live there is no piped NG so it would be propane delivered to a storage tank which is even more expensive.
Also the winters are mild here so basically everyone has either a heat pump or the further south you go it's just heat strips because heat is rarely used so not worth the cost.
So any kind of blanket statement about heat pumps vs gas heat would be folly, but due to improvements in cold weather heat pumps and solar power are allowing them to make much more sense in more places.
There are many advantages to decoupling fuel combustion from its energy use, burning NG at a power plant relatively efficiently with much better emission controls, then distributing on electric grid for use more than just heating, while allowing the home to heat from many different energy sources and allow for grid down backup as well.
Not to mention, lots of places have time of use electricity pricing which makes it even worse. This is the problem with running my heatpump when its cold, some of the coldest times (right before dawn) coincide with peak time-of-use prices
I’ve tried. For it to be at all viable on my property, I’d need to cut down a bunch of trees. I’d rather keep the trees and pay someone else with solar panels.
ASHRAE—an HVAC organization—has data on the coldest and hottest days for areas so that you can design things for the coldest or hottest 1% of the year (4 hottest/coldest days):
I think that if you have an older, leaky/ier, less-insulated house you may need to 'brute force' heating your (probably older) domicile. But if you have a <4 ACH@50 air tightness, and reasonable insulation levels, a good portion of the US population could make do with a heat pump.
Mitsubishi publishes data were they have 100% heating capacity at -15C, which some models being 100% at -20C and -23C:
It is warmer than -16C/3F at Chicago (O'Hare) for 99% of the time (i.e., except for 4 days a year), and warmer than -18.7C/-2F for 99.6% of the time (2 days).
ASHRAE are the folks that publish the heating/cooling standards that are used in building codes for estimate heating/cooling equipment capacities (Manual J) and selecting the right equipment (Manual S).
Here's a PDF with a lot of locations in the US and CA (and other countries further down), and if you look under the "Heating DB" column, you'll find very few US locations that have -30F under the 99% (or even 99.6%) sub-columns:
So unless you're in AK, MN, or ND, long runs of temperatures colder than -20F/-30C don't happen too often. Of course if you have a leaky house with little insulation, you're throwing money out the window/door, so the first consideration for a good ROI is better air sealing and insulation.
I think the comment was saying below 30F and below 10F. Much warmer than you're saying.
Also..
> It is warmer than -16C/3F at Chicago (O'Hare) for 99% of the time (i.e., except for 4 days a year), and warmer than -18.7C/-2F for 99.6% of the time (2 days).
If my heat doesn't work for those days, I'm kind of boned. Four days per year without a working heat pump? That's a mess.
So gas hash higher reliability and is cheap for the times you need heat the most, whereas heat pumps might not work and are not cheap at the times you need them the most?
I’ve had a gas furnace keep me and the water heated multiple times in a cold weather power outage.
That's one of the older style units. Starting in 2007 when Mitsubishi introduced their "Hyper-Heating Inverter" heat pumps, and continuing with Fujitsu and Daikin following with similar technology in the 2010-12 timeframe, and others a few years later, heat pumps got way better in the cold.
Mitsubishi's maintain 200%+ efficiency down to -4℉ (-20℃) and 150% down to -22℉ (-30℃) [1]. Only a few towns in the continental US get below that, and even those aren't going to get cold enough long enough to make it worth it an an all electric home to switch to your emergency electrical resistance heating.
Their capacity doesn't start dropping until you get down to 23℉ (-5℃), dropping to 76% at -13℉ (-25℃).
I've got one about 8 years old, and it does just fine down to 0°F (it hasn't gotten colder than that here). It doesn't even have any kind of auxiliary heat.
It's fine. The only difference when it's super-cold is that the air coming out of it isn't as warm, so the heating cycle stays on for a longer proportion of the time. But it keeps it 70°F inside no problem at all.
Though it’s worth noting that that first 2 ton rated unit is putting out 0.5 tons (6k BTU/hr) at that temp and rating.
That’s not going to be particularly helpful for a structure that needed 24k BTU/hr during warmer temps, meaning the owner of the unit is likely mixing in a lot of 1.0 BTUs to meet the heat loss at -13°F.
> Though it’s worth noting that that first 2 ton rated unit is putting out 0.5 tons (6k BTU/hr) at that temp and rating.
I just did a quick search for "all" units and sorted the result list/table by COP@5F. If one was actually shopping/designing a solution then a more nuanced search criteria would be used.
Further, you'd probably want to do a (US ACCA) Manual J calculation to first determine how much energy is needed (j = joules)
I don't know what sort of heat pump systems are common in the US, but Sweden (and AFAIK Norway and Finland as well), are probably >%80 heat pump for single family homes (most apartments are community heating at least in the larger cities). So it's absolutely now problem to run a heat pump even if it is very cold outside, but if you want to improve efficiency in areas that are super cold you can drill into the ground for a heat sink (those are called Bergvärme in Sweden).
Regarding cost, in most of the countries I've lived in a large fraction of the cost in the gas bill was the distribution cost. So once you switch to a heat pump, you also switch to electric cooking and even if heating with electricity would be significantly more expensive you would still win. Is that different in the US?
It varies significantly by locale. I've seen people post online about how it made little sense to keep just one gas appliance because of significant savings. I'm in Iowa, which typically heats on natural gas in urban areas. I have a natural gas central furnace and water heater. My clothes dryer is electric, and I have a 3 head heat pump which I use for comfort in a couple rooms. The house is an early 2000's standard builder-grade home.
For September, $12.31 of my $27.01 gas bill was variable based on my consumption.
In December, $84.82 out of my $99.65 total was consumption driven.
I've run numbers on whether it'd make financial sense to go electric for heating, and the break even point is in the 30-40 degree vicinity. With temperatures 20 and under a healthy chunk of the year, unfortunately the added expense doesn't make financial sense.
Maybe totally fine for you. But that will not be "totally fine" for much of the US when they are expecting to keep their house at 72 degrees and the new technology they got talked into can't do it.
The tech has limits and cold weather states can't avoid that or the reputation will get really bad and the tech will fail.
I'm not sure if you've lived in prolonged -15F areas, but many conventional heating systems struggle too... especially in poorly insulated houses. People often have wood stoves or other ways to compensate.
I've not had much trouble with Xcode in the past 15+ years I've been using it. Its biggest warts involve Interface Builder, which is easily avoidable by using code for UI instead of XIBs or storyboards.
With Android Studio, I'd say the ways that it being an IntelliJ IDE puts it above Xcode are cancelled out by other aspects of Android development, which can be abysmal. Swift Package Manager and Clang/llvm code stripping have never made me want to tear my hair out the way that Gradle and Proguard have for example.
This depends entirely on how well the thing you're using bothered to support multiple platforms.
Browsers are pretty much the gold standard here, ironically. You might have to care if it's Firefox or Chrome but it's very rare for you to have to care if it's Firefox on Windows or Mac or Linux. It's exactly why React is simultaneously horrible and everywhere.
So it can be done, it's just a question of whether that framework has done it well, ideally while also doing other things well (unlike React).
There's nothing wrong with guessing, just be clear that it's a guess and not an attempt to represent known facts. I don't know if the comment got edited or just reads more clearly on a second pass, but at first it felt ambiguous.
People are booing because HN commenters generally kind of meritocratic and lowkey idolize company leaders. It's an unpopular opinion here, but executives aren't in their positions because they are smarter than everyone else, or better at business, or have better product ideas. They're generally there for less meritocratic reasons: They went to the right prep school and college, they were friends with the right people already in the executive class, they rubbed elbows with other business leaders in MBA school, they golf at the right country clubs. Then they get that sweet VP title and fail upward all the way to retirement.
They pay people to watch every play of every game and apply a formula that grades the relative difficulty in order to develop their advanced statistical models.
Some of this stuff has been automated, but a lot still hasn't and still relies on the "eye test".
To my knowledge, in game betting for MLB is pretty rare. But using in game data to bet in game can be profitable. I had a system I used for in game betting NBA that was profitable. I just hated watching NBA all night.
And it won't even work during some of the coldest winter weeks when you _really_ need it to work.
Maybe I would consider it if I was in, like, Nevada or somewhere.
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