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Apparently it doesn’t work in Germany. Physics work differently here. At least that’s what our corrupt politicians want us to think
I hear that too. Not just politicians, there's loads of experts lecturing on heating technologies. It's just too cold in Germany for heat pumps. Doesn't stop Scandinavia from getting them, granted, but in Germany it's just too cold. No point. Sorry.
I can't get an electrician and contractor to come install one (as an AC mainly) inside of 6 months, and I've been trying to find one for 6 months.
The heat is actually killing me I can't sleep and have other health problems. I brought a dual hose unit from the US with me I'm running on a voltage converter and it's the only thing keeping my apartment livable.
Germany has corrupt politicians? Say it ain't so!
/s (all politicians are corrupt)
Makes sense. Heat pumps are one of the few heating systems that can achieve greater than 100% efficiency. (energy in vs total heat output)
As long as you can keep the evaporator above the evaporation temperature of your compressed refrigerant, you're golden. Burried lines are excellent for that in colder climates, but the space for it isn't always easy to find.
It's a little more expensive, but most places can find the space by drilling straight down. Still worth it from what I've seen in most places.
Bless you. I love that guy. So gosh darn nit-picky on the details and its the best!! Never thought hour long videos on heat pumps or refrigerators or car headlights would hold my attention or be a favorite part of my week but he makes it happen.
The study isn't wrong, but it's also not right, IMO.
This doesn't seem to mention the cost of the energy, just how "efficient" it is.... which, honestly, "efficient" can imply several things, and they don't seem to clarify what (at least from my first pass of this doc).
The issue is that even if you're getting 3-4 times as much heating/cooling as you could with something else, per jule of energy potential that is put into the system (in whatever form that is), if your energy cost for that source of power is high, it's going to lose the financial argument every time.
Sure, a natural gas furnace will consume "more fuel" and produce less effective heat than a heat pump, but if you're paying 10x the cost for electricity, then you're still going to end up spending more per degree of heating than with the cheaper fuel.
Where I am, electricity is pretty cheap, but natural gas is tremendously cheaper per jule.... so we can actually pay less by using the "inefficient" fuel for our home.
I don't think the numbers are dramatically different at the end of the day, but this study seems to completely ignore the core issue that most people will be concerned with.... which is: "will this save me money?" Which is arguably the more important metric.
honestly, “efficient” can imply several things, and they don’t seem to clarify what (at least from my first pass of this doc).
How would you like to define it?
How about this for an analogy - which of these two is more efficient:
Plant some wheat in your back yard, buy fertilised eggs to hatch into chickens, plant tomatoes and basil, plant an olive to grow a tree, and eventually, years down the track, you can make yourself a bowl of pasta.
Notice your next door neighbour already cooked some pasta and made more than they can eat. Ask politely and they'll just give you a serving.
Obviously - the second option is more efficient, and that's effectively what a heat pump does. They don't heat up your home, they just take a bit of heat from the air outside and move (pump) it into your home. It's far far more efficient than creating new heat from scratch with a gas system.
Exactly how much more efficient will depend on the outdoor and indoor air temperature, and on the brand/model of heat pump you buy, and other factors (such as the length of the pipe between the outdoor unit and the indoor unit). You really should ask for specific advice on your home - but in general, a heat pump is extremely efficient.
Where I am, electricity is pretty cheap, but natural gas is tremendously cheaper per jule… so we can actually pay less by using the “inefficient” fuel for our home.
Have you actually looked into it, or are you just making assumptions?
I can tell you that my heat pump, in my house (yours will be different), in my climate, adds about $5 per week to my electricity bill. Is your gas bill less than $5 per week?
Or at least - that's how much it cost before I had solar panels. Now that I have solar... it uses about 20% of the power typically produced by the solar panels on my roof leaving plenty of excess power that we sell to the grid for about the same amount of money as what we spend buying power overnight. Since we installed solar our entire electricity bill is about $0 (and we use power for a bunch of other stuff, including to cook breakfast and dinner when the sun typically isn't shining*). We don't have a large solar system either - in fact, installing solar cost less than installing heat pumps.
(* our solar system comes with instruments and software to measure our consumption - and I can tell you that heating up a family meal with an electric cooktop uses more electricity than heating an entire house with heat pump... because the cooktop is creating heat, and the heat pump is simply moving heat)
Where I am, electricity is pretty cheap, but natural gas is tremendously cheaper per jule… so we can actually pay less by using the “inefficient” fuel for our home.
Most of the push towards rapid adoption of heat pumps is happening in Europe, where geopolitical developments (to put it mildly) caused gas prices to spike last winter. The nature of the natural gas logistics means that different continents can have wildly different prices (unlike petroleum, where you can always throw it on a ship and send it from where it's cheap to where it's expensive), so a lot of European countries are seeing these debates play out against the backdrop of their own energy markets. Germany passed a law this year that would phase out new gas furnace installations, so that's why a lot of the debate is happening with a focus on German markets.
Whether (or how quickly) a transition to heat pumps pays for itself in euros will depend a lot on what happens in the future to gas and electricity prices.
if your energy cost for that source of power is high, it’s going to lose the financial argument every time.
How high, is the question. How much more is electricity where you live that heat pumps "lose the financial argument every time"? Where I'm from a kWh of electricity is roughly 2.8-3x that of natural gas, so most modern heat pumps will beat that, some by quite a margin.
If globalpetrolprices.com is to be trusted and Canadian natural gas is 0.063 CAD and electricity is 0.165 CAD you're very much in the same boat with a 2.6 ratio. Most heat pumps should be able to beat a 2.6 SCOP even in Canada.
So, sure, the study only looks at COPs and not at overall cost, but I think it's not unreasonable to expect home owners to be able to divide electricity price by gas price and compare it to the SCOP of heat pumps on offer.
What's also interesting is that you have to factor in the costs and CO2 emissions of the fuel source and it's delivery method. A new building code for a county in my area was adopted which requires calculations for energy efficient HVAC systems and also CO2 emissions with those systems. Surprisingly, natural gas has less CO2 emissions associated with it, while electricity is 2.86 times as much. This is because grid electricity is mostly produced by fossil fuels, then needs to be delivered to the site but there are many losses along the way. So even if the all electric equipment is twice as efficient as the equivalent natural gas equipment, it still contributes more CO2 production. This is part of the issue with phasing out natural gas and moving to all electric in its current state. But with that is the push (and requirements) to produce energy on site and shift towards net zero energy for commercial sites, which is definitely better than using grid power from an emissions standpoint.
No shit
A sticking point I encountered - the drop in efficiency as the weather gets colder means you need a unit sized to heat your home on the coldest days you expect to encounter. So you need to buy a heat pump that's larger than you need for 98% of the year just so you don't freeze that other 2%. In addition to higher cost an oversized unit is less efficient because it's cycling more.
So this is where "heating strips" or "backup heating" come in, and then I get we've come full-circle.
I don't see how this is "full circle". In places where it does get that cold, most homes already have a form of heating for the house. Adding on a heat pump or, at least in my case in the Midwest, replacing the central AC unit with a heat pump just means that you're only kicking that original heating system on a few days out of the year. That's a massive reduction in use compared to being the only source of heat for half the year.
It's a problem that new construction homes would need to fix if they don't want an NG connection at all, but it's not unsolvable.
You'd usually run two or more units in a cascade/multiplex when requiring large amounts of power rather than having one giant unit. Means you can turn off one or more units entirely for low heating demand.
I think modern inverter units are not less efficient when oversized. They are able to run at varying levels rather than cycling.
The only downside (in comparison to fuel burners) is complexity. Heat pump systems are extremely complex with a lot of parts that could get fucked up over time.
A gas furnace is as simple as it gets with almost no moving parts. Coal/wood furnaces are a bit more complicated if you don't want to blow 100% of the emissions into the air... you need good well maintained filter systems. But it's still far less complex than a heat pump.
So I understand the appeal of furnaces. Simpler systems are easier to understand, are harder to break and easier to repair/maintain.
I think that problem is tackled too rarely in these articles. If you can't take away the fear that people will have a higher upfront invest and higher maintenance costs and higher failure risk, that makes it too convenient to cling to what they know and understand.
Edit: oven --> furnace
Eh, I think you might think heat pumps are more complicated than they are. I think they're about as complicated as a furnace. At the end of the day, in both your just pumping a gas from one place to another, changing the state of the gas, and then running that past air to heat or cool it.
Heat pumps dont replace gas ovens. They replace central heating systems. They are not that much more complex then a central heating system and come with a lot fewer safety concerns. And heat pumps are not new technology - they are just AC units that can run in reverse to heat instead of cool. We already know how well they work and how often they fail and a lot of the world is already reliant on them just as much as others are reliant on gas central heating.
Now if electricity was just less than 3x the price of gas, we'd be winning.
Unfortunately gas costs a lot less for the same amount of energy. So it's only going to save you money if you use simple electric heating.
For those of us on gas boilers, the prospect of a system paying for itself (maybe) in 50 years time isn't overly enticing.
Has not been updated for a while, but relevant link…
https://www.energy.gov/eere/buildings/residential-cold-climate-heat-pump-challenge
In this context is a "heat pump" the same thing as an inverter air conditioner?
A split system.
That's what most of Australia uses and looks like the pic but Ive never heard them called a heat pump.
A split system AC is a heat pump in any context. So is a refrigerator. They're all the same technology that move energy via a refrigerant's latent heat by compressing it into a warm part and letting it expand into a cold part.