3 ms·

Decoupling of energy prices from fossil fuel is going to be spreading around the globe. It's not that hard to grasp. If you are spending non trivial percentages

Decoupling of energy prices from fossil fuel is going to be spreading around the globe. It's not that hard to grasp. If you are spending non trivial percentages of your GDP on stuff that you burn once in exchange for some twh of energy delivered, lowering that significantly will have a notable impact on your trade balance. Recent events in the middle east will have made a few countries keenly aware of how overly dependent they are on stuff coming from that region and how easily their economies are disrupted when stuff goes wrong there. I live in Berlin, electricity is rather expensive here and people are not treating their gas dependence with enough urgency yet. The city is surrounded by flat country side with lots of wind mills and solar installations. Yet most apartment buildings in the city are still gas heated. Mine is no exception. I have to pay into fueling the gas boiler every month to the extent of about 150ish euro per month. Down from 250ish during the worst of the aftermath of the Russian gas pipeline shut down. I'd love my building to be switched to a heat pump. That's 1800 euro down the drain every year. I'll take a 30-40% cut on that please. It's technically very feasible and measured over 10-20 years, there should be a very clear financial payoff. Done right it should pay for itself probably within a decade. The building has about 20 apartments. Monthly gas bills are 2.5K based on yearly statements. Or about 30K. All out the chimney. That's one hell of a budget to tackle a bit of energy efficiency in the building. But this is where Germany is its own worst enemy. We're talking a lot of vested interests. Nimby's somehow blocking the notion of literally saving money (as opposed to setting it on fire and chucking it out the chimney). A lack of incentives. A lot of bureaucracy, etc. Even the decision to stop building completely new buildings without a gas connection is somehow controversial in this country where gas is expensive. It is in the middle of a years long gas crisis of its own making and it can't get the decision to stop hitting itself with the proverbial hammer actioned. A bit of system thinking could turn this around relatively quickly though. For example starting to think of this as investments with clear ROI as opposed to just cost would change the decision making and could also open up a lot of financing. Banks love investments with predictable ROI, for example. And Germany has an excellent credit rating. However, Germany is grid locked on an irrational fear of financing and debt. It has very little of it relative to e.g. the US or even most other EU countries. It also has huge infrastructure problems. Addressing those requires investment. Investment requires financing. Investments have ROIs which should enable said financing. But that's where penny pinching politicians seem to have a mental block confusing investments for cost and consistently opting to "save cost" rather than to invest. And generally not seeing the forest for the trees. But the picture is pretty clear. Switch most house holds to heat pumps while at the same time investing in cables, on/off-shore wind, a bit of solar on the side. With lots of battery storage. Etc. would do wonders for the amounts of gas it has to import at great cost. The country has millions of apartment blocks like mine using about 2-3x more energy than needed for heating. Almost all of it in gas form. A program to change those buildings could be executed in 10-15 years and break even in about the same time. It would result in many billions of savings in gas imports per year. That's the few percent of GDP that makes the difference between growth or recession. Germany has been in and out of recession for the last few years. Even powering that exclusively with gas fired electricity plants would yield substantial savings. And it already is transitioning to a grid that is mostly not gas powered. This should be a no brainer. But it somehow isn't. And that's just domestic heating.

distances 7mo ago
I wonder how heat pumps would work for apartment building central heating systems. The circulated water has to be a lot hotter than heat pumps are capable of, as far as I've understood. Is there already a system that could viably replace gas in the existing building stock? Another problem is that most people in Berlin/Germany are renting, so the incentives do not align. The building owner doesn't pay for the heating, so they are unlikely to do any investments where the upside is for the tenants only.
- tialaramex 7mo ago
  Heat pump hot water is very common in Europe. Just as it's possible for the pump to make a box so cold that food stays frozen despite the hot summer's day in Florida, it's also possible to heat up a tank of water this way, it just costs more energy. Unlike modern natural gas boilers which have only a very small tank of water kept hot and use a fire to make more on demand with only a few seconds of delay (you might not even realise this is happening, but of course it isn't actually instant and so there is a small tank of very hot water) the heat pump will need a large tank because you're going to put about a day's supply of hot water in the tank and gradually, over a whole day, re-heat it as needed.
  - distances 7mo ago
    The problem is the old building stock (say, large apartment buildings from early 1900s) which isn't energy efficient at all, and on cold winter days require very hot water to keep warm. The radiators were designed with assumption that the water can be boiling hot (coal/gas). It doesn't seem feasible to renovate everything, so I'm wondering what are the practical options. A hybrid system where a gas boiler is kept for the peak demand?
    - tialaramex 7mo ago
      There's no chance at all that you're using boiling hot water (373K) because that stuff is both dangerous and unreasonably expensive to make at volume. My guess is that what you're thinking of is the water being say 320 to 340K, which is obviously far warmer than you'd heat a home, but isn't boiling water. Heat pumps will be more efficient at lower temperatures, so maybe it's keeping that tank of water at 320K while your gas boiler was 330 or even 340K -- but the gas boiler is more efficient for lower temperatures too, ask any manufacturer or installer, the way to get lower costs is to turn down the local thermostat, it's just that people are used to "instant" heat from a gas boiler and won't tolerate answers like "Run it for a whole day" whereas that is what your heat pump needs. It is true that because of this "Run it all day" approach an uninsulated home is so expensive to heat that it's impractical, when I grew up there was ice inside my bedroom window when I woke on a winter's morning, it had been under 270K at night, and a gas boiler would heat it in an hour or so -- but that's not because it's literally impossible with heat pumps it's just far too expensive.

distances 7mo ago

I wonder how heat pumps would work for apartment building central heating systems. The circulated water has to be a lot hotter than heat pumps are capable of, as far as I've understood. Is there already a system that could viably replace gas in the existing building stock? Another problem is that most people in Berlin/Germany are renting, so the incentives do not align. The building owner doesn't pay for the heating, so they are unlikely to do any investments where the upside is for the tenants only.

tialaramex 7mo ago
Heat pump hot water is very common in Europe. Just as it's possible for the pump to make a box so cold that food stays frozen despite the hot summer's day in Florida, it's also possible to heat up a tank of water this way, it just costs more energy. Unlike modern natural gas boilers which have only a very small tank of water kept hot and use a fire to make more on demand with only a few seconds of delay (you might not even realise this is happening, but of course it isn't actually instant and so there is a small tank of very hot water) the heat pump will need a large tank because you're going to put about a day's supply of hot water in the tank and gradually, over a whole day, re-heat it as needed.
- distances 7mo ago
  The problem is the old building stock (say, large apartment buildings from early 1900s) which isn't energy efficient at all, and on cold winter days require very hot water to keep warm. The radiators were designed with assumption that the water can be boiling hot (coal/gas). It doesn't seem feasible to renovate everything, so I'm wondering what are the practical options. A hybrid system where a gas boiler is kept for the peak demand?
  - tialaramex 7mo ago
    There's no chance at all that you're using boiling hot water (373K) because that stuff is both dangerous and unreasonably expensive to make at volume. My guess is that what you're thinking of is the water being say 320 to 340K, which is obviously far warmer than you'd heat a home, but isn't boiling water. Heat pumps will be more efficient at lower temperatures, so maybe it's keeping that tank of water at 320K while your gas boiler was 330 or even 340K -- but the gas boiler is more efficient for lower temperatures too, ask any manufacturer or installer, the way to get lower costs is to turn down the local thermostat, it's just that people are used to "instant" heat from a gas boiler and won't tolerate answers like "Run it for a whole day" whereas that is what your heat pump needs. It is true that because of this "Run it all day" approach an uninsulated home is so expensive to heat that it's impractical, when I grew up there was ice inside my bedroom window when I woke on a winter's morning, it had been under 270K at night, and a gas boiler would heat it in an hour or so -- but that's not because it's literally impossible with heat pumps it's just far too expensive.