He's talking about an electric furnace rather than a heat pump.
California Moves To Ban Natural Gas Furnaces / Heaters
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As they say it's complicated.
https://www.energyvanguard.com/blog/is-a-heat-pump-more-efficient-than-a-furnace/
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It's not really complicated, just not something most people think about. That guy does a good job explaining it.
Ultimately, you also have to consider the temperature range you are using the heat pump in as well. They only work within a specific envelope and typically fall back on resistive or gas once outside it. This is a great way to reduce your household emissions in places with green grids, but if the grid is filthy and your fallback is resistive, you may actually be a worse polluter.
In California, where most heating is going to happen when the sun goes down, at which point most power is provided by gas, a heat pump and a high efficiency furnace are going to be close to a wash. That doesn't mean we should discourage people from buying them however, they have cooling advantages during the summer and hopefully, the grid will get greener going forward.
I thought I would add that TC Energy is putting in another parallel section of 48 inch gas pipeline near Fernie BC along the existing Foothills Pipeline. It’s called looping and is basically adding sections of line to lower back-pressure allowing more flow with the same compression horsepower. It also provides more gas storage to aid in providing volume in winter months. Where is that gas going? California.
We weren't talking about heat pumps, just older vs newer electric furnace.
Doesn't matter how old the electric furnace is, it's still the same 100% efficient.
And it's a false economy to install an electric furnace with only air conditioning, because the additional cost of a heatpump over a straight cool system was less than $800 last time I checked.
I think it is a local ordinance, not state.
This works fine if it is a new building but it would probably only works if you have natural gas backup with heat pump.
Not if it is a heat pump in moderate climate.
Are you saying an electric furnace with air conditioner with 100% efficient resistance heat is better than a heatpump with 200% - 400% efficiency because the upfront cost is about $800 less???
EDIT: Some definitions:
Air handler: Metal box with a fan in it.
Electric furnace: Air handler with resistance heating coils installed (these are usually field-installed, the air handler does not come with them).
Electric furnace with air conditioner: Air handler plus resistance heating coils plus evaporator A-coil plus cool only (NO HEATPUMP) condensing unit.
Heat pump: Air handler plus resistance heating coils plus evaporator A-coil plus heat pump condensing unit.
The cost difference between the last two is about $800 and consists mostly of a reversing valve, a more sophisticated thermostat, and a defrost control board.
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It "depends".
In some area the furnace is really not used more than being a regulation compliance device, in that case the $800 less + more durable design will win in the long run.
Still, the main argument is whether you need NG if you can use heat pump and AC anyways. It is possible you don't need NG so might as well only use it as backup.
If the furnace isn't really needed then there may be no benefit to installing a heatpump. I think you'd need to look at the total heating degree days of a typical winter in that area to make that determination.
As far as needing NG, I live where it gets down below 20F in the winter, sometimes as cold as 5F, one year it got below 0F overnight, and I don't have access to NG and propane is too expensive, so I heat my house with a heat pump. I run it with the aux heat disabled except for when it goes into defrost.
Why not just warn or give a timeout to the offenders? Many worthwhile threads get locked because of a few numbskulls.
Actually, if gas hookup fees aren’t too high, or even possibly LP/propane, gas would be handy to run a backup generator IN CASE of cold weather power failure, to keep the heat pump system running.
Why not a water cooled LP/natural gas generator engine with the radiator used to provide heat for the living space? Always wondered why that wasn't done. Why do we burn natural gas in a furnace instead of using it to run a generator, and using the heat from the generator to warm the space and use the electricity to run a heat pump?
I have a 45 year old boiler in Minnesota no less. I ran the numbers to switch it out and the payback is 20 years. Not happening because it's just not worth it. Until it breaks.....
Probably because the generator has to be huge otherwise the waste heat is not sufficient, and the cost to build such a system to be reliable is going to be too high.
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Yeah - we run large waste heat recovery systems on gas turbines - but don’t even bother on V16 CAT’s …
A natural gas generator consumes about 10,000BTU of natural gas per horsepower per hour. A 10HP engine would therefore consume 100,000BTU per hour, and produce as waste heat about 70% of that, depending on how efficient the engine is.
I was looking for a good place to respond, but that was Berkeley with the first local ordinance that barred new natural gas hookups. A Ninth Circuit ruling just put that on hold on the premise that federal law controls whether or not natural gas is allowed or not because only the federal government can regulate energy consumption under this law. It was a restaurant association that sued. And I certainly get it - especially with some kinds of cooking where there's not likely an acceptable substitute for gas ranges.
https://www.ktvu.com/news/berkeleys-natural-gas-ban-overturned-by-federal-appeals-court
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