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Indeed, though in colder climates you do have the problem that peak electricity demand is precisely when you get minimum solar production. But in sunnier, warm

by rgmerk 2y ago

Indeed, though in colder climates you do have the problem that peak electricity demand is precisely when you get minimum solar production. But in sunnier, warmer parts of the world (which notably includes India, Pakistan, Bangladesh, Indonesia, Nigeria, Egypt, Ethiopia, Iran, Mexico, and Brazil, amongst others), over the next few decades it's hard to see anything much competing against solar and batteries for the bulk of energy usage.

bkor 2y ago
> But in sunnier, warmer parts of the world Though solar panels prefer if it isn't too hot. Still, any such inefficiencies are easily outweighed by their low cost. In Netherlands it is common to install practice (and advised) more Wp than the inverter can handle. Maybe also a solution if it gets too hot, make it up by having more panels.
thehappypm 2y ago
That isn’t true yet, because most cold places don’t use electricity for heating; in Boston for example the norm is oil or gas furnaces. Europe typically uses gas for heating, as we all learned during the Ukraine war’s beginning. When I lived in the Boston area, our electricity use, peaked in the summer during air-conditioning season. That is, until we got a heat pump, then our electricity spiked like crazy in the winter. but we are long way from having the majority of homeowners using heat pumps for their primary heat source. (Also heat pumps are kinda awful compared to furnaces in my experience so we might never get there).
- smolder 2y ago
  >heat pumps are kinda awful Heat pumps work great under the right circumstances. In cold climates like Boston and north of it, ideally you want ground source, which means digging deep (or wide) holes to flow water through instead of just pulling heat from outside air. Alternatively, (or additionally, ideally) they're best used in homes with very tight air envelopes, good insulation, and heat/energy recovery ventilation (HRV/ERV) systems. Installed in radiant heating systems in well-built houses, heat pumps are fantastic and you'll be comfortable all year for pennies on the dollar. The reality is that most (US) construction, especially older, is just terrible in terms of air seal and insulation. Couple that with a potentially undersized air-source heat pump, which gets inefficient as the outside temp gets near the low end of its operating range, and you will not have a great time. But even then they are a good way to supplement gas heating, so you can limit furnace use to the coldest weeks of the year and do the environment a favor, as well as cool in the summer.
  - thehappypm 2y ago
    The issue with supplementing with gas is that you still need a gas furnace. And if you have a gas furnace, why spend $10k+ on a heat pump?
    - smolder 2y ago
      You shouldn't spend that much. If you need an air conditioning system, making it a bidirectional heat pump is negligible unless people are trying to rip you off. (They are) Are you one of the grifters or just confused?
      - thehappypm 2y ago
        Comparing a cold-climate AC to a cold climate heat pump shows how confused YOU are. ACs in cold climates are cheap. Cooling a house down 20 degrees doesnt take a lot of BTUs. Plus they’re just cheaper per-BTU and a typical northeast homeowner is going to be comfortable installing a cheap brand because it’s not life-or-death if your AC goes out. When you start talking about having a heat pump being the primary heat source in a cold climate home, that’s a different ball game. First you need WAY more BTUs to heat a house in winter lows — even NYC hits single-digits most winters, that’s a 60 degree temperature differential. And you need to be prepared for the worst temperatures which basically necessitates a top-end brand like Mitsubishi which is rated down to historic-ish lows. Not to mention that many homes don’t have central ducts, so converting to a heat pump means ductwork or mini splits.. All in all it’s not really a negligible thing.
        smolder 2y ago
        No, the difference in cost between central air conditioning (a heat pump that works in one direction) and a heat pump that works in both directions is negligable unless you're being ripped off.
        thehappypm 2y ago
        Just saying something doesn’t make it true. Here’s a concrete example that took 5 minutes to find. Two condensers from the same company, same seller, same SEER, same series, same tonnage, except the second does heat. The heat pump is 29% more expensive. 2 Ton 14.3 SEER2 Trane Air Conditioner Condenser - RT Series. $1615 2 Ton 14.3 SEER2 Trane Heat Pump Condenser - RT Series. $2090 https://hvacdirect.com/trane-a4ac4024d1-2-ton-14-3-seer2-air-conditioner-condenser-runtru-by-trane-158002.html https://hvacdirect.com/trane-a4ac4024d1-2-ton-14-3-seer2-air... https://hvacdirect.com/trane-a4hp4024d1-2-ton-14-3-seer2-heat-pump-condenser-runtru-by-trane-157888.html https://hvacdirect.com/trane-a4hp4024d1-2-ton-14-3-seer2-hea...
- haccount 2y ago
  There's a green trend in much of central-north europe to use electric heating, mainly by promoting air heat pumps.
  - rgmerk 2y ago
    And despite the handwringing, air source heat pumps can work fine in pretty cold places (eg Norway). You can, right now, buy air source heat pumps rated to -28C (-14F). While not enough for record lows in, say, Chicago or Toronto, it's plenty for places like New York, Seattle, and Vancouver.
    - thehappypm 2y ago
      Rated to -14F doesn’t really bring a lot of comfort. NYC has reached that temperature; NJ has reached -34. In a typical winter you might stay above zero every minute of every day. But when that big arctic blast comes through and your heat pump efficiency tanks, right at the same time your house is bleeding its heat faster than ever, that could be pretty dangerous. So, every heat pump installer recommends a having a backup (at least the dozen I’ve talked to in the Northeast US). it’s hard to convince regular people that heat pumps are the future when you’re also told to have a backup.
      - rssoconnor 2y ago
        This year I installed a heat pump with a 10kW auxiliary heater for my home in southern Ontario. With an appropriate air handler, both the heat pump and auxiliary heater can run at the same time. The setup seems fine to me. If anything having a backup heat source makes me feel secure. A lot of things can go wrong with a gas furnace; some things can go wrong with a heat pump; but 10kW of electric restive heat is dead simple and just by itself it can provide 34000 BTU/h, which is 60% of the output of my old gas furnace. I don't think the duty cycle of my gas furnace ever exceeded 60% running time. The auxiliary heater consists of two 5kW heaters, so even if one fails, there is still the other.
        thehappypm 2y ago

by rgmerk 2y ago

bkor 2y ago

> But in sunnier, warmer parts of the world Though solar panels prefer if it isn't too hot. Still, any such inefficiencies are easily outweighed by their low cost. In Netherlands it is common to install practice (and advised) more Wp than the inverter can handle. Maybe also a solution if it gets too hot, make it up by having more panels.

thehappypm 2y ago

That isn’t true yet, because most cold places don’t use electricity for heating; in Boston for example the norm is oil or gas furnaces. Europe typically uses gas for heating, as we all learned during the Ukraine war’s beginning. When I lived in the Boston area, our electricity use, peaked in the summer during air-conditioning season. That is, until we got a heat pump, then our electricity spiked like crazy in the winter. but we are long way from having the majority of homeowners using heat pumps for their primary heat source. (Also heat pumps are kinda awful compared to furnaces in my experience so we might never get there).

smolder 2y ago
>heat pumps are kinda awful Heat pumps work great under the right circumstances. In cold climates like Boston and north of it, ideally you want ground source, which means digging deep (or wide) holes to flow water through instead of just pulling heat from outside air. Alternatively, (or additionally, ideally) they're best used in homes with very tight air envelopes, good insulation, and heat/energy recovery ventilation (HRV/ERV) systems. Installed in radiant heating systems in well-built houses, heat pumps are fantastic and you'll be comfortable all year for pennies on the dollar. The reality is that most (US) construction, especially older, is just terrible in terms of air seal and insulation. Couple that with a potentially undersized air-source heat pump, which gets inefficient as the outside temp gets near the low end of its operating range, and you will not have a great time. But even then they are a good way to supplement gas heating, so you can limit furnace use to the coldest weeks of the year and do the environment a favor, as well as cool in the summer.
- thehappypm 2y ago
  The issue with supplementing with gas is that you still need a gas furnace. And if you have a gas furnace, why spend $10k+ on a heat pump?
  - smolder 2y ago
    You shouldn't spend that much. If you need an air conditioning system, making it a bidirectional heat pump is negligible unless people are trying to rip you off. (They are) Are you one of the grifters or just confused?
    - thehappypm 2y ago
      Comparing a cold-climate AC to a cold climate heat pump shows how confused YOU are. ACs in cold climates are cheap. Cooling a house down 20 degrees doesnt take a lot of BTUs. Plus they’re just cheaper per-BTU and a typical northeast homeowner is going to be comfortable installing a cheap brand because it’s not life-or-death if your AC goes out. When you start talking about having a heat pump being the primary heat source in a cold climate home, that’s a different ball game. First you need WAY more BTUs to heat a house in winter lows — even NYC hits single-digits most winters, that’s a 60 degree temperature differential. And you need to be prepared for the worst temperatures which basically necessitates a top-end brand like Mitsubishi which is rated down to historic-ish lows. Not to mention that many homes don’t have central ducts, so converting to a heat pump means ductwork or mini splits.. All in all it’s not really a negligible thing.
      - smolder 2y ago
        No, the difference in cost between central air conditioning (a heat pump that works in one direction) and a heat pump that works in both directions is negligable unless you're being ripped off.
        thehappypm 2y ago
        Just saying something doesn’t make it true. Here’s a concrete example that took 5 minutes to find. Two condensers from the same company, same seller, same SEER, same series, same tonnage, except the second does heat. The heat pump is 29% more expensive. 2 Ton 14.3 SEER2 Trane Air Conditioner Condenser - RT Series. $1615 2 Ton 14.3 SEER2 Trane Heat Pump Condenser - RT Series. $2090 https://hvacdirect.com/trane-a4ac4024d1-2-ton-14-3-seer2-air-conditioner-condenser-runtru-by-trane-158002.html https://hvacdirect.com/trane-a4ac4024d1-2-ton-14-3-seer2-air... https://hvacdirect.com/trane-a4hp4024d1-2-ton-14-3-seer2-heat-pump-condenser-runtru-by-trane-157888.html https://hvacdirect.com/trane-a4hp4024d1-2-ton-14-3-seer2-hea...
haccount 2y ago
There's a green trend in much of central-north europe to use electric heating, mainly by promoting air heat pumps.
- rgmerk 2y ago
  And despite the handwringing, air source heat pumps can work fine in pretty cold places (eg Norway). You can, right now, buy air source heat pumps rated to -28C (-14F). While not enough for record lows in, say, Chicago or Toronto, it's plenty for places like New York, Seattle, and Vancouver.
  - thehappypm 2y ago
    Rated to -14F doesn’t really bring a lot of comfort. NYC has reached that temperature; NJ has reached -34. In a typical winter you might stay above zero every minute of every day. But when that big arctic blast comes through and your heat pump efficiency tanks, right at the same time your house is bleeding its heat faster than ever, that could be pretty dangerous. So, every heat pump installer recommends a having a backup (at least the dozen I’ve talked to in the Northeast US). it’s hard to convince regular people that heat pumps are the future when you’re also told to have a backup.
    - rssoconnor 2y ago
      This year I installed a heat pump with a 10kW auxiliary heater for my home in southern Ontario. With an appropriate air handler, both the heat pump and auxiliary heater can run at the same time. The setup seems fine to me. If anything having a backup heat source makes me feel secure. A lot of things can go wrong with a gas furnace; some things can go wrong with a heat pump; but 10kW of electric restive heat is dead simple and just by itself it can provide 34000 BTU/h, which is 60% of the output of my old gas furnace. I don't think the duty cycle of my gas furnace ever exceeded 60% running time. The auxiliary heater consists of two 5kW heaters, so even if one fails, there is still the other.
      - thehappypm 2y ago