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by phkahler 1164 days ago
>> Of course it's extremely important to switch people to electrified heating systems, regardless of their efficiency.

You could use a gas fired heat pump. It won't work as an air conditioner, but it won't stress the grid and could even work when the power goes out.

2 comments

you are better of adding with a gas plant to the grid, which can be up to 84% efficient (if you reuse the heat generated by the turbine as well)

https://en.wikipedia.org/wiki/Combined_cycle_power_plant

And even if you don't, a 60% efficient gas turbine at the power-plant, paired with a 3+ COP heat pump in the home will be 2x more efficient than burning gas directly in the home.

Using gas in an adsorption heat-pump is quite inefficient and unlikely to break even economically. Perhaps a gas turbine home boiler could be produced, that combines a mechanical heat-pump with a high efficiency combined cycle turbine; alas, they do not exist and would be very expensive. It's a startup idea.

A home gas furnace can easily surpass 90% efficiency. Turning the gas into electricity and then including the transmission losses to the home is going to be way below 84% efficiency. Plus reusing the heat produced at the power plant is much more difficult than reusing the heat produced in the home, when the purpose is heating the home in the first place.
Up to 64% as stated in the article. The 84% efficiency statement is in reference to the theoretical efficiency of a Carnot cycle.
64% for the turbine only
No. Definitely not.
>and could even work when the power goes out.

AFAIK gas furnaces still need electricity for the fans to work. When you have no electricity you at best have a glorified fireplace. It's probably going to be a worse than a regular fireplace because it's not designed to output heat to its surroundings.

The fan of a furnace takes little power. It can be run off of a small generator, which ~every homeowner in New England has.

A heat pump cannot run off a small generator.

Two notes: in a modern insulated home in not so cold climate 1kW absorbed is enough to heat a home with -20℃ outside, with is still far more than a simple fan but a power level a classic small generator can provide. The second note is that if you get gas from pipes the supplier need electricity to pump it, so it might have autonomous power or not, you can't be sure.

As a safeguard I prefer a classic wood burning stove, witch is far from being comfy but works alone, reliably and I can stock enough woods or emergency source it almost anywhere...

Living in the French Alps I do not know much about New England homes (insulation, ventilation, power system, ...) but IME gas heating systems are in the mean LESS reliable than heat pumps and electricity + wood is the combo to be comfy normally and backed up in case of trouble.

Yeah I totally agree. Heat pump with a wood stove / furnace as a second heat source is the way to go.

It's not unheard of to go multiple days without electricity after a bad snow storm, so I would never trust a heat pump alone. When you need them the most, they are the least efficient and reliable. And I want to have a fireplace anyway, so it makes sense to make it functional.

> It can be run off of a small generator, which ~every homeowner in New England has.

This is absolutely not true. I actually don't know anyone who lives in an urban area in New England that has a generator. And I know some who live in fairly rural Maine that don't have one.

Generators are not ubiquitous, or even common, in New England.