ᐅ CO2 Footprint of Gas Heating vs. Heat Pumps in New Construction
Created on: 17 Nov 2024 16:30
K
Konsument4
Recently, there was a discussion among acquaintances about the idea of installing a gas heating system in a new single-family house in 2025 (according to my source/Statista, about 10% still did this in 2023). I researched this topic somewhat (including with the help of ChatGPT, o1-preview) and came across results that seem somewhat out of step with the current general attitude.
- In a 300 sqm (3,230 sq ft) KfW-55 house (minimum standard for 2024, energy efficiency class A with 40 kWh/m2/year), the additional CO2 emissions from a gas heating system compared to a heat pump amount to about 1.6 tons of CO2 per year. (Calculation: Gas: 300 m2 × 40 kWh/m2/year = 12,000 kWh/year; 12,000 kWh × 0.202 kg CO2/kWh = 2,424 kg CO2/year; Heat pump - annual performance factor 4.5, German electricity mix 300 g CO2/kWh: 12,000 kWh ÷ 4.5 = 3,429 kWh/year; 3,429 kWh × 0.3 kg CO2/kWh = 1,028.7 kg CO2/year => 2,424 kg CO2/year − 1,028.7 kg CO2/year = 1,395.3 kg CO2/year)
- Compensating 1.6 tons of CO2 costs about 40 euros on atmosfair. Two tons cost 50 euros.
- In 2024, a heat pump costs roughly 35,000 euros, while a gas heating system costs around 15,000 euros. (There is no direct subsidy for heat pumps in new builds.)
That means, if I compensate the additional CO2 emissions from a gas heating system over 20 years, it costs me about 800 euros. If I pay 1,000 euros, I have still done something positive for the environment overall. On the other hand, there is an upfront cost difference of about 20,000 euros for the heat pump. Spending 20,000 euros for an outcome I can achieve with 1,000 euros seems disproportionate to me.
Currently, the price per ton of CO2 is about 30 euros; even if this price rises to 400 euros by 2045 (allegedly a worst-case scenario), I would still come out cheaper with gas (1.6 tons × 400 euros/ton = 640 euros per year in 2045, and likely significantly less before that).
Of course, my calculation is based on various average values, but unless I am seriously wrong in at least one area, the result seems quite clear: If I install a gas heating system in a new single-family home and at least compensate for the CO2 emissions, it appears I come out cheaper and could still do something good for the environment with the savings.
Am I missing something? What else should be considered? Does the calculation contain a major incorrect assumption or wrong average value?
PS: I have seen the thread about gas heating systems 23/24, but in my opinion, the topic of the CO2 footprint was not discussed there, and towards the end, the thread went off-topic anyway.
- In a 300 sqm (3,230 sq ft) KfW-55 house (minimum standard for 2024, energy efficiency class A with 40 kWh/m2/year), the additional CO2 emissions from a gas heating system compared to a heat pump amount to about 1.6 tons of CO2 per year. (Calculation: Gas: 300 m2 × 40 kWh/m2/year = 12,000 kWh/year; 12,000 kWh × 0.202 kg CO2/kWh = 2,424 kg CO2/year; Heat pump - annual performance factor 4.5, German electricity mix 300 g CO2/kWh: 12,000 kWh ÷ 4.5 = 3,429 kWh/year; 3,429 kWh × 0.3 kg CO2/kWh = 1,028.7 kg CO2/year => 2,424 kg CO2/year − 1,028.7 kg CO2/year = 1,395.3 kg CO2/year)
- Compensating 1.6 tons of CO2 costs about 40 euros on atmosfair. Two tons cost 50 euros.
- In 2024, a heat pump costs roughly 35,000 euros, while a gas heating system costs around 15,000 euros. (There is no direct subsidy for heat pumps in new builds.)
That means, if I compensate the additional CO2 emissions from a gas heating system over 20 years, it costs me about 800 euros. If I pay 1,000 euros, I have still done something positive for the environment overall. On the other hand, there is an upfront cost difference of about 20,000 euros for the heat pump. Spending 20,000 euros for an outcome I can achieve with 1,000 euros seems disproportionate to me.
Currently, the price per ton of CO2 is about 30 euros; even if this price rises to 400 euros by 2045 (allegedly a worst-case scenario), I would still come out cheaper with gas (1.6 tons × 400 euros/ton = 640 euros per year in 2045, and likely significantly less before that).
Of course, my calculation is based on various average values, but unless I am seriously wrong in at least one area, the result seems quite clear: If I install a gas heating system in a new single-family home and at least compensate for the CO2 emissions, it appears I come out cheaper and could still do something good for the environment with the savings.
Am I missing something? What else should be considered? Does the calculation contain a major incorrect assumption or wrong average value?
PS: I have seen the thread about gas heating systems 23/24, but in my opinion, the topic of the CO2 footprint was not discussed there, and towards the end, the thread went off-topic anyway.
Konsument4 schrieb:
The invoice is clearly itemized above – please tell me where it is “nicely” calculated; that is the real question. You are projecting the present into the future,
electricity prices, gas prices, CO2 penalties – compensations, durability and prices of the systems.
I see an error margin of +/-30% here, because of the future and political decisions.
That way I could manipulate the result to fit my goal.
K
Konsument417 Nov 2024 20:05chand1986 schrieb:
The misleading calculation lies in the fact that price optimization does not reflect resource optimization. If environmental protection was truly the goal, all “compensation” measures would be implemented even when people only install heat pumps. Instead, there is just window dressing. Of course, any emission that could be avoided is unnecessary and therefore harmful, even if it is offset. This is because the reference point is never the current state, but what could have been done better instead.
Economic efficiency and climate balance are not the same. If environmental protection were really the aim, then according to my calculation, I would argue that you should keep your gas bill and invest the saved 20,000 euros in CO2 offsetting. This could compensate for about 700 tons of CO2. Unless CO2 offsetting is fraud, but as I said, that discussion goes beyond the scope here.
C
chand198617 Nov 2024 20:15Konsument4 schrieb:
If it were truly about environmental protection, then according to my calculation, you should ignore the gas bill and invest the saved 20,000 euros in carbon offsetting instead. That could compensate for about 700 tons of CO2. Unless carbon offsetting is a scam, but as I said, this discussion is going too far for me at this point. Exactly. And this could be consistently followed through: Until people live in small apartments in multi-family buildings, where the heating system works much more efficiently per person on a centralized basis. And all the money intended for buying a house is instead invested in environmental and/or climate protection. There is a reason why this does not happen. Almost no one will do what you logically recognized above—even though, of course, you are factually correct.
K
Konsument417 Nov 2024 20:16Nida35a schrieb:
You are including the present in the future calculations,
electricity prices, gas prices, CO2 penalty payments – compensations, durability and costs of the systems.
I see an error margin of +/-30% here, due to the future and political decisions.
That allows me to conveniently adjust the result to fit my goal. So if I understand your post correctly, this is about possible costs in EUR. Okay, in that case, I come to the conclusion that I am saving 19,000 euros (20k - 1k for the CO2 compensation) today and will then have to buy expensive gas in the future instead of cheaper (possibly even self-generated) electricity. That is true, although 19,000 euros seems generous to me for that.
And actually, it wasn’t about really saving EUR in the first place, but about the fact that gas heating currently has such a bad CO2 reputation. My claim is that the CO2 footprint can be (over-)compensated—and significantly in this calculation. If that is really wrong, then the discussion makes no sense. But I don’t think so.
First, I would review the quotes ... regarding the price aspect.
And then ... we simply can no longer afford to continue releasing CO2 into the atmosphere. This should be avoided wherever possible, because I quote
And then ... we simply can no longer afford to continue releasing CO2 into the atmosphere. This should be avoided wherever possible, because I quote
The first 10 percent disappears quickly, but that’s not very much. The second part takes centuries to millennia, but that’s about 80 percent,” says Ed Boyle, Professor of Ocean Geochemistry at MIT. He says the last carbon dioxide that enters the atmosphere takes tens of thousands of years to disappear again.
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chand198617 Nov 2024 20:22Konsument4 schrieb:
The point wasn’t really about saving money in euros, but that gas heating currently has such a bad CO2 reputation. My claim is that the CO2 footprint can be (over)compensated—and significantly so in this calculation. If that’s actually wrong, then the discussion doesn’t make sense. But I don’t believe that. You can overcompensate: Just like you wrote to me in your last reply. Use the price difference between gas heating and a heat pump to buy green land, plant trees, and make sure nothing is cleared for your entire life. Or buy and operate solar systems. Invest in flue gas desulfurization for a coal plant in Africa.
What you can’t do is meaningfully “compensate” something for 1000€ (euros). Simply because the whole concept of emissions at one point plus compensation elsewhere isn’t coherent.
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