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I recently read Gates’ book How To Avoid a Climate Disaster which left me with the impression that the overriding factor in building costs is the energy require

I recently read Gates’ book How To Avoid a Climate Disaster which left me with the impression that the overriding factor in building costs is the energy required (and CO2 produced) for construction, heating, and cooling. Unfortunately I didn’t see any mention of energy or carbon in this post. Seems like the biggest breakthrough would be a pre-construction estimate of energy costs over, say, 30 years. Similar to the Energy Star sticker on appliances sold in the US which tell you the cost to run a given appliance with typical usage compared to the range for other models. This would allow you justify spending more upfront for better insulation, HVAC, air sealing, etc. and recoup that over time. At scale this would allow our civilization to be more energy efficient and reduce the need to build more power plants. This suggestion stood out: ”...move to resistance heating and thermoelectric cooling“ Unless I’m missing something, this would be a step backward. Modern heat pumps are 3-4x more efficient than resistance heating, since they aren’t creating heat but moving it from one place to another. For cooling, if the author is referring to Peltier type thermoelectric cooling, the same applies: heat pumps are many times more efficient. The building revolution we need is one that cheaply produces extremely energy-efficient homes, IMO.

rhinoceraptor 5y ago
This video is a great explainer on heat pumps [1]. The TL;DR is that they are essentially nothing more than air conditioners that run in the opposite direction. Plus, a heat pump and an air conditioner can be combined into a single system. 1: https://youtu.be/7J52mDjZzto https://youtu.be/7J52mDjZzto
- sgerenser 5y ago
  Not just can be combined they effectively always are. I’m not aware of any residential heat pumps sold in the US at least that don’t also operate in cooling mode. The additional cost is basically just a reversing valve.
wffurr 5y ago
Heat pumps need plumbing and installation which increases the construction cost. Agreed that they are the way to go, but it's not going to bring down construction costs. The author's strawman proposal was a nuclear battery for effectively unlimited onsite power with no marginal cost in order to minimize construction costs.
- throw0101a 5y ago
  > Heat pumps need plumbing and installation which increases the construction cost. So do radiant floor heating or straight-out radiators. And force air needs ducting, which takes up a lot of volume: and unless you use floor trusses instead joists, you have to be a creative with the design of your runs. What HVAC system would you suggest?
  - wffurr 5y ago
    How should I know? It depends on what you are trying to optimize for. The author seems to think if you want to minimize on-site construction costs, a radioisotope thermal generator is the way to go. That's pretty far out there. My comment was simply explaining why the author brought up resistive electric heat at all. Though why not just use the waste heat from the RTG, but then we are back to needing ducting I guess. Ultimately it depends on what tradeoffs you want to make and your local climate. I think district-based aka neighborhood scale geothermal is promising from a sustainability perspective, but introduces a significant coordination problem.
NumberWangMan 5y ago
Good point. Also note that a 4-family home is going to be generally much more energy efficient than 4 single-family homes, since there are fewer walls that leak heat to the exterior. So the author's recommendation to build more multi-family dwellings is on point in that respect.
- nitrogen 5y ago
  Shared-wall homes have pretty terrible tradeoffs in terms of privacy, air quality, and (lack of) soundproofing, though.
  - foobar33333 5y ago
    They don't have to. The apt building I live in must be built really well because I have never heard a single sound from the people around me. I can only just hear muffled talking/music while standing in the hallway but never from within my own apt.
  - hinkley 5y ago
    Some states have code that fixes the sound problem, but the cost is higher $/sq ft costs.
    - 41b696ef1113 5y ago
      Do you have a sense on how bad the increased cost is for reasonable sound isolation (talking/tv not garage band)? Because I have dealt with loud neighbors, and if the problem could be ameliorated for an extra $1/m or something else trivial, I will be enraged that it is not mandated everywhere.
wyager 5y ago
> I recently read Gates’ book I hope you didn’t intend to extract any valuable information from that. > the overriding factor in building costs is the energy required (and CO2 produced) for construction, heating, and cooling. Unfortunately I didn’t see any mention of energy or carbon in this post. That’s because when an eco-activist like Gates, who has no clue about environmental economics, talks about “costs”, he is completely bullshitting. Clearly he gave you the wrong impression, at least. The overriding factor in the cost of essentially everything is energy, if you decompose the cost network far enough. Obviously engineers and home builders are not stupid and if there was some massive efficiency increase they could exploit, the would do so.
perceptronas 5y ago
in EU we have these stickers. You cannot build houses with lower "tier" energy "stickers" anymore. New houses have to be built very efficiently and be certified where their yearly energy costs will be calculated. (HVAC, air sealing, building materials like windows/insulation and so on are taken in account)
fighterpilot 5y ago
Shouldn't we also account for housing density? A dwelling may be as energy efficient (in terms of cooling/heating) on a per-dwelling basis as a high-rise apartment, but this may not be the case when considering the impact on things like transportation etc.

rhinoceraptor 5y ago

This video is a great explainer on heat pumps [1]. The TL;DR is that they are essentially nothing more than air conditioners that run in the opposite direction. Plus, a heat pump and an air conditioner can be combined into a single system. 1: https://youtu.be/7J52mDjZzto https://youtu.be/7J52mDjZzto

sgerenser 5y ago
Not just can be combined they effectively always are. I’m not aware of any residential heat pumps sold in the US at least that don’t also operate in cooling mode. The additional cost is basically just a reversing valve.

wffurr 5y ago

Heat pumps need plumbing and installation which increases the construction cost. Agreed that they are the way to go, but it's not going to bring down construction costs. The author's strawman proposal was a nuclear battery for effectively unlimited onsite power with no marginal cost in order to minimize construction costs.

throw0101a 5y ago
> Heat pumps need plumbing and installation which increases the construction cost. So do radiant floor heating or straight-out radiators. And force air needs ducting, which takes up a lot of volume: and unless you use floor trusses instead joists, you have to be a creative with the design of your runs. What HVAC system would you suggest?
- wffurr 5y ago
  How should I know? It depends on what you are trying to optimize for. The author seems to think if you want to minimize on-site construction costs, a radioisotope thermal generator is the way to go. That's pretty far out there. My comment was simply explaining why the author brought up resistive electric heat at all. Though why not just use the waste heat from the RTG, but then we are back to needing ducting I guess. Ultimately it depends on what tradeoffs you want to make and your local climate. I think district-based aka neighborhood scale geothermal is promising from a sustainability perspective, but introduces a significant coordination problem.

NumberWangMan 5y ago

Good point. Also note that a 4-family home is going to be generally much more energy efficient than 4 single-family homes, since there are fewer walls that leak heat to the exterior. So the author's recommendation to build more multi-family dwellings is on point in that respect.

nitrogen 5y ago
Shared-wall homes have pretty terrible tradeoffs in terms of privacy, air quality, and (lack of) soundproofing, though.
- foobar33333 5y ago
  They don't have to. The apt building I live in must be built really well because I have never heard a single sound from the people around me. I can only just hear muffled talking/music while standing in the hallway but never from within my own apt.
- hinkley 5y ago
  Some states have code that fixes the sound problem, but the cost is higher $/sq ft costs.
  - 41b696ef1113 5y ago
    Do you have a sense on how bad the increased cost is for reasonable sound isolation (talking/tv not garage band)? Because I have dealt with loud neighbors, and if the problem could be ameliorated for an extra $1/m or something else trivial, I will be enraged that it is not mandated everywhere.

wyager 5y ago

> I recently read Gates’ book I hope you didn’t intend to extract any valuable information from that. > the overriding factor in building costs is the energy required (and CO2 produced) for construction, heating, and cooling. Unfortunately I didn’t see any mention of energy or carbon in this post. That’s because when an eco-activist like Gates, who has no clue about environmental economics, talks about “costs”, he is completely bullshitting. Clearly he gave you the wrong impression, at least. The overriding factor in the cost of essentially everything is energy, if you decompose the cost network far enough. Obviously engineers and home builders are not stupid and if there was some massive efficiency increase they could exploit, the would do so.

perceptronas 5y ago

in EU we have these stickers. You cannot build houses with lower "tier" energy "stickers" anymore. New houses have to be built very efficiently and be certified where their yearly energy costs will be calculated. (HVAC, air sealing, building materials like windows/insulation and so on are taken in account)

fighterpilot 5y ago

Shouldn't we also account for housing density? A dwelling may be as energy efficient (in terms of cooling/heating) on a per-dwelling basis as a high-rise apartment, but this may not be the case when considering the impact on things like transportation etc.