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Thermoelectric heating stands at the brink of commercialization

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Re: Thermoelectric heating stands at the brink of commercialization

#61

Post by ctechbob »

thsksbd wrote: post #54
ctechbob wrote: post #50

Dupont will see that this never sees the light of day. Just like how we don't use butane/propane/CO2 as refrigerants which are just as safe as most of the flourocarbons but have the downside of being too cheap to make any money off of.

Well they're also inflammable and not as good as CFCs. Kinda how we don't use toxic ammonia as a refrigerant. For what it's worth, my mini fridge and my chest freezer use some hydrocarbon refrigerant. They're littered with warning signs not to puncture them.

Most of the FC's are highly toxic when exposed to fire.

R-1234yf is not only (slightly) flammable but also releases hydrogen fluoride and carbonyl fluoride when exposed to fire, but this is what is in almost all new cars.

I've run a propane/butane mix in an R12 car before and the fact that it was flammable didn't bother me a bit. The 14 gallons of gas would worry me more than 12oz of propane going up.

Re: Thermoelectric heating stands at the brink of commercialization

#62

Post by ZeroGravitas »

davidw wrote: post #38
Kye wrote: post #32

Earlier quoted context omitted.

At 20F that's probably the backup heat kicking in. Heat pumps start losing their efficiency advantage around 40. edit: apparently I was misinformed, but it doesn't seem like something worthy of being downvoted into oblivion.

No, because the installer set it up right at 20. We do have a gas furnace that kicks in below that. It'd be amazing if someone put together some kind of dynamic calculator that could take electricity and natural gas prices and examine inside temperatures based on a smart thermostat system and rejig the cutoff temperature based on all of it.

There are hybrid heat pumps that do exactly this.

Re: Thermoelectric heating stands at the brink of commercialization

#63

Post by com2kid »

ericbarrett wrote: post #48
jfoutz wrote: post #19

Earlier quoted context omitted.

I thought pellet stoves got hot enough to be pretty clean. Co2, yes, but not much else?

Residential pellet stoves sound great but in practice they are not reliable (moving mechanical parts that operate at high temps, electronics poorly shielded from said temps—the manufacturers are pretty shady in my experience), and the cost of fuel varies quite a bit and can be very high. Compare to a wood stove that needs no electricity and can burn just about any combustible solid. Modern wood stoves are pretty effi…

> but in practice they are not reliable (moving mechanical parts that operate at high temps, electronics poorly shielded from said temps

25 years ago my grandmother bought a pellet stove that lasted for 15 years with semi-regular maintenance.

Her next stove, same company, broke all the time and lasted less than 10 years, with much higher ongoing costs.

Enshitification strikes again!

Re: Thermoelectric heating stands at the brink of commercialization

#64

Post by com2kid »

ctechbob wrote: post #50

Dupont will see that this never sees the light of day. Just like how we don't use butane/propane/CO2 as refrigerants which are just as safe as most of the flourocarbons but have the downside of being too cheap to make any money off of.

Isobutane is one of the most common refrigerants in use today...

Chemical companies do plenty of actual evil things, there is no need to spread false claims!

Re: Thermoelectric heating stands at the brink of commercialization

#65

Post by ctechbob »

com2kid wrote: post #64
ctechbob wrote: post #50

Dupont will see that this never sees the light of day. Just like how we don't use butane/propane/CO2 as refrigerants which are just as safe as most of the flourocarbons but have the downside of being too cheap to make any money off of.

Isobutane is one of the most common refrigerants in use today... Chemical companies do plenty of actual evil things, there is no need to spread false claims!

Is that why Dupont and Honeywell have been sued repeatedly for anticompetitive practices when it comes to refrigerants?

HC's are gaining in popularity but they are being fought every step of the way because they are cheap and there's no money to be made.

Re: Thermoelectric heating stands at the brink of commercialization

#66

Post by pjc50 »

magicalhippo wrote: post #41
antisthenes wrote: post #9

Earlier quoted context omitted.

What in the world are you talking about? The hardest part of installing AC is the ductwork. Swapping out the outside + inside heat exchanger unit is a 1-person 3-4-hour job. Sorry if some HVAC company scammed you, but it's definitely not a 3 person job, unless we're talking some commercial building 5+ ton units.

We got a Mitsubishi Kaiteki[1], which is a mini-split from what I can gather. We just call them "air to air heat pumps" here in Norway. Anyway, the install itself was about $400, took one guy a few hours like you said. Another $200 for the electrician which had to hook up a dedicated circuit for it as per regulations, though he did it as part of a larger job so would have been $300 as a stand-alone deal. Total it was…

What does the inside/outside setup look like for those? One unit on the inside, one on the outside, short plumbing run between?

Re: Thermoelectric heating stands at the brink of commercialization

#67

Post by pjc50 »

bilsbie wrote: post #4

I’d pay a premium for a solid state AC or heat pump. It’s absurd how much they cost to install. And I don’t get why replacing one is an all day job for three people. There should be standard connections they just plug into. Like a dishwasher.

Replacing like for like should be a fairly easy job. But replacing between different systems does seem to be a nightmare.

It's interesting that Americans are retrofitting them into HVAC systems, while in the UK we're trying to retrofit into natgas/water based systems, and seemingly the Scandinavians have gone for .. I'm not sure but it seems cheaper?

I upgraded to a "hybrid" system because it was the least cost / minimal change, so I continue to have natgas hot water which can optionally heat the radiators if the control unit deems it economic (no, it doesn't have dynamic pricing). And that was still £15,000 even though it could reuse all the existing radiators. Apparently having 8mm "microbore" copper plumbing is a problem for "low temperature" heat pump systems, because they rely on higher throughput.

At the end of winter I'll write-up my bills and evaluate the experience.

Re: Thermoelectric heating stands at the brink of commercialization

#68

Post by pjc50 »

davidw wrote: post #38
Kye wrote: post #32

Earlier quoted context omitted.

At 20F that's probably the backup heat kicking in. Heat pumps start losing their efficiency advantage around 40. edit: apparently I was misinformed, but it doesn't seem like something worthy of being downvoted into oblivion.

No, because the installer set it up right at 20. We do have a gas furnace that kicks in below that. It'd be amazing if someone put together some kind of dynamic calculator that could take electricity and natural gas prices and examine inside temperatures based on a smart thermostat system and rejig the cutoff temperature based on all of it.

My Vaillant system claims to do that, but it doesn't have dynamic input of pricing so you have to type it in on the head unit. I'm not sure it's even possible to get an API for dynamic pricing of UK energy prices.

Re: Thermoelectric heating stands at the brink of commercialization

#69

Post by magicalhippo »

pjc50 wrote: post #66
magicalhippo wrote: post #41

Earlier quoted context omitted.

We got a Mitsubishi Kaiteki[1], which is a mini-split from what I can gather. We just call them "air to air heat pumps" here in Norway. Anyway, the install itself was about $400, took one guy a few hours like you said. Another $200 for the electrician which had to hook up a dedicated circuit for it as per regulations, though he did it as part of a larger job so would have been $300 as a stand-alone deal. Total it was…

What does the inside/outside setup look like for those? One unit on the inside, one on the outside, short plumbing run between?

Yeah, you can see the two units here[1], also has dimensions for them under specifications.

The plumbing is covered by a plastic cover, both for protection and looks.

We have a small wooden "shed" for the outside unit[2], to protect it from getting clogged up with snow and also to make it less visible. Both the plastic cover and the "shed" is painted in the same color as our home, so blends in nicely.

[1]: https://www.varmepumpeservice.no/mitsubishi-kaiteki-6300-hvi...

[2]: https://mee.no/produkt/varmepumpehus-impregnert/

Re: Thermoelectric heating stands at the brink of commercialization

#70

Post by wojciii »

bilsbie wrote: post #4

I’d pay a premium for a solid state AC or heat pump. It’s absurd how much they cost to install. And I don’t get why replacing one is an all day job for three people. There should be standard connections they just plug into. Like a dishwasher.

(sorry about being a bit off-topic, but I got triggered by standard).

Funny that you mention standards.

It should be possible to swap out the multimedia device in your car with a new one. It should use a standard connector and form factor.

So I guess we should start working on standards that would improve our world and make reuse possible instead of buying even more new shit all the time.

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