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[deleted] t1_j9cf1zk wrote

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bradland t1_j9cfdar wrote

Heat pump efficiency can reach 300%. The maximum efficiency when using natural gas to heat a home directly is 100%. So as crazy as it sounds, burning mangas to generate electricity actually results in net gains in efficiency when using a heat pump instead of combustion based heating.

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[deleted] t1_j9cg5q1 wrote

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gregra193 t1_j9cgoh8 wrote

Heat pump efficiency being >100% is very real.

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[deleted] t1_j9ckgcn wrote

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Jamesgardiner t1_j9cp557 wrote

You’re an engineer who can’t figure out that burning 10 units of gas to make 4 units of electricity, then putting that through a heat pump to pull 12 units of heat into your home is better than just burning the gas in your home?

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bradland t1_j9dd2rq wrote

Sometimes people really blow my mind. That person tripled down so hard they’d rather delete their account than incorporate new information.

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bradland t1_j9cjy72 wrote

Nope. I know, it sounds like it violates the laws of thermodynamics, but it’s very real. The reason is that heat pumps don’t generate all of their own heat; they just move it around.

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Sleepdprived t1_j9cmisz wrote

No... he is correct you can MOVE 5 times the amount of heat with the same energy it takes to MAKE 1 unit of heat.

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r2k-in-the-vortex t1_j9clnvv wrote

No it's not, because you are not paying for the heat you remove from outside air. Of course it's no perpetum mobile, but in terms of heat in your home vs fuel spent, yes it is over 100% efficient.

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Sacrifice_bhunt t1_j9clb49 wrote

The idea being that your power grid can eventually switch over to clean energy sources. But if you buy a traditional furnace, you are guaranteed to burn fossil fuels for the life of the appliance.

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[deleted] t1_j9cm4dh wrote

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Blue_Trackhawk t1_j9d21z0 wrote

Yeah, there's a lot of moving parts determining whether this is immediately beneficial to the environmental impact of climate control or not.

Lower demand for fuel at each household, but increased demand for fuel at the power station; what net change in fuel cost does this create?

Heat pumps tout up to 300% efficiency, but that is only achieved in ideal weather conditions; how often is it operating well short of that?

There may be economies of scale using fuel for power generation at the power plant; how much more efficient is it? How do transmission losses factor into that?

There are plenty of talking points for or against. I don't think everyone should just go convert a perfectly functional system to electric, and for others, conversion may be financially irresponsible. If we're looking at this as a phase (get it?) in a larger plan to reduce dependence on fossil fuel for energy needs, then it seems like an eventually worthwhile change and not just passing the buck or kicking the can.

What we have been seeing are things happening in parallel. Efforts to reduce generation emissions while also increasing residential and commercial structure and systems efficiency.

In terms of that last mile efficiency, this is just the next evolution to previous efforts to increase efficiency in lighting. Remember when the vast majority of light bulbs used 60-100 watts? I even used to have a 300-watt halogen lamp! Now we are seeing 10-15 watts. That's huge! And looking at the efficiency of AC units for a 3ton unit, at 14 seer, it was like running 25 of those old light bulbs; a 25 seer unit would be like 14 of those old light bulbs, or maybe 100-150 modern led lights. We shifted energy demand away from lighting, and by moving away from combustion heat, shifting demand more to electric heat, but it is not an equal exchange. As generation becomes more efficient, we're actually looking at the end game of a major shift in energy sources and consumption. We are also doing our part adopting more EV and PHEV vehicles (a whole other can or worms). Let's not get pessimistic and take the wind out of the sails of people who want to switch from a furnace to a heat pump now! Things feel like they are moving in the right direction, slowly but surely.

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Squirrel09 t1_j9d46s5 wrote

I too refuse to make progress, until the perfect solution is presented.

No duh there's still more work to do. Nobody is saying this is the end, but a very good step forward.

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m-s-c-s t1_j9db6jf wrote

My state pairs it with other incentives like home energy efficiency upgrades and discounts on a whole class of energy upgrades. You get loans with preferential interest rates (like a couple % off the rate) if you let them do a home energy audit.

So like, I got heat pumps on a line of super cheap credit because I'm willing to let them help me plug holes in my sieve of a house. I get thousands of dollars in tax incentives back.

That same home energy audit is good for like a year? Maybe more? It also gets me major tax incentives on buying solar panels, which you can also get super cheap lines of credit. So whaddaya know, I'm doing that too.

Between the savings in heating and cooling costs, I don't think the whole rig will be free, but it'll be cheaper than keeping my existing heating cooling solution even without the leak seal I'm getting. From a real cost standpoint, provided electricity and oil don't become ludicrously cheap simultaneously suddenly, it's about what I would've paid to get old school central air alone and stay on grid power. Even if it does, I now have a system that lets me handle major power outages due to weather without being miserable. If it goes up, I'm better than break even.

'Murica or something! 🇺🇸

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