In any given house, per unit of heat generated is going to leak out at the same rate no matter how that heat is produced, no? Whether that heat comes from a gas boiler, a heat pump, or a resistive heater shouldn't matter...?
I think the way costs scale is important - a big gas boiler doesn't cost that much more, you're just burning more gas, but a big heat pump costs more. Heat pumps put more of the cost up front and less down the track.
So if the uninsulated homeowner is facing a $10k bill for a massive heat pump they can say "ooh what if I spend $1k on insulation" and they could get the sizing down and spend $6k.
There's really no fundamental difference. The heat pump itself doesn't know whether you've got a massive house that's well insulated or a tiny house that's poorly insulated, it's just a heat load.
With a heat pump, you really need to make an effort to keep the heat inside, as the heat output can’t match a boiler. So you need to redesign the whole building.
They’re not at all what most people living in a typical single family dwelling would think of as a furnace, which may be a forced air or water-based baseboard radiator setup.
A heat pump can keep up with a traditional furnace type system just fine, but not a boiler system because the buildings with boilers are so old they don’t have much insulation at all.
In Britain a boiler is a device in a single family home that provides heating by using gas or electricity to heat water which is then piped to radiators. It is also used to heat water for showers. Boilers can be quite small, many modern boilers are “combi” boilers that heat water on demand without a separate hot water tank. My boiler is the size of a suitcase.
Older properties generally have a boiler and insulated hot tank. This means that you need to plan your showers and heating requirements in advance by “putting the water on” to ensure there’s enough hot water in the tank.
Forced air heating is rarely used in the UK and people are generally not familiar with the concept.
But it’s quite stupid: In both countries you need AC, so why not install a mini split heat pump+AC system like the Nordics and the US?
It also doesn’t help that they don’t tax fossil gas like electricity, hence you often need subsidies to make it worthwhile to switch
Almost no residential building in Germany has AC, and I'm unsure what you mean by "need". Also the buildings are built to last, so no remodeling every few years like in the US. That means one is stuck with most of the utility built into the house from the start. Remodeling a regular central European brick-and-mortar house to accommodate floor heating or duct vents is difficult and expensive.
There's a fine line: if you have green energy, why would you care? Consuming more green energy actually improves the overall situation, as more money is available to build out green energy in the first place (especially with things like Green Planet Energy). It's just the need for moral superiority for some folks that's stopping AC distribution in central Europe imho.
Sales are on the increase as summers are hotter. We even see apartment dwellers in Norway getting these
https://www.verivox.de/presse/13-prozent-der-deutschen-nutze...
Really it's besides the point - you might not need a plunger to unclog the toilet or a fire extinguisher or a first aid kit often, but when you do, you really need it!
And for rest district heating is common enough. And there a centralised solutions make sense, even real efficiency gains like using waste heat from factories and datacenters.
Less than 5% of houses in the UK have AC
In particular, half the houses in Britain have no insulation in the walls at all. In fact older houses tend to handle heat better - they are naturally drafty, there is a loft taking the heat, they have high thermal mass, and maybe they are even damp and have a leak and mould. All that takes away from the heat.
But now we get newbuild apartments without AC's, and that should be a crime. These buildings are air tight, have zero ventilation, trap heat, no thermal mass so they don't stay cool from the night, and in some of them you can't open windows. And you are not allowed to install a split system because the landowner will never give permission.
https://www.statista.com/statistics/292265/insulation-in-dwe...
Air-water heat pumps are a thing
It's not about the technology. It's about how electricity is priced very highly compared to gas in the UK. Our electricity in Western Australia is only double the cost per kWh compared to gas, but one kWh of electricity generated three kWh of heat in a reverse cycle air con so it's a no brainer.