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Heat pump disappointment for climate-minded Massachusetts state senator

willbrownsberger.com

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Re: Heat pump disappointment for climate-minded Massachusetts state senator

#81

Post by nkurz »

tgflynn wrote: post #76
nkurz wrote: post #66

Earlier quoted context omitted.

Elsewhere he says that his heat pumps are two Daikin RJQ18TAVJUA: https://ashp.neep.org/#!/product/56878/7/25000///0 . Much of the other information is probably available elsewhere on his site: https://willbrownsberger.com/heat-pumps/ As I mention in another comment, I think the base of the problem is that the heat pumps he has installed are simply inappropriate for his climate.

> I think the base of the problem is that the heat pumps he has installed are simply inappropriate for his climate. The question is whether there is such a thing as a heat pump that's appropriate for use in the Northeastern US. It seems unlikely to me that someone with this person's level of engagement would have stupidly chosen to install the wrong kind of heat pump or chosen an installer incapable of recommending t…

I agree it's still a somewhat open question, but I think the data is that Massachusetts is probably on the side where it can make sense with the right equipment. Here's a real world analysis of a heat pump in Connecticut that averaged an full heating season COP of about 3.0: https://www.nrel.gov/docs/fy13osti/56393.pdf

I disagree that he's unlikely to have chosen a bad installer. They seem to have installed a non-cold-climate heat pump in Massachusetts. If that's true, I think it's strong evidence that they were not competent and should not have been trusted. I guess one could argue that this was a low probability choice, but I think it's as likely there were simply no more competent installers available in his area.

Re: Heat pump disappointment for climate-minded Massachusetts state senator

#82

Post by SketchySeaBeast »

trey-jones wrote: post #57
SketchySeaBeast wrote: post #40

Earlier quoted context omitted.

I'm also wondering about the cost of maintenance and repair (say, in case of an underground refrigerant leak). I too would love to be wrong - it'd be a decent solution for a cold Albertan winter. It doesn't matter that the air is -40 if you're below the frost line.

I have two self-installed ground source heatpump units (6 tons total) in operation since summer of 2016 with no maintenance except for the loop pump. I was using two very old second-hand pumps until last summer (one for each unit), when one impeller completely disintegrated. I took the opportunity to reconfigure the plumbing and wiring a little bit to use only one pump (more modern, theoretically better fit for my sy…

How deep are your lines buried? Did you need to be concerned about the frost line?

Re: Heat pump disappointment for climate-minded Massachusetts state senator

#83

Post by SketchySeaBeast »

phpisthebest wrote: post #4
tgflynn wrote: post #2

It's good to see a politician actually doing their own analysis rather than just following every fad. It's a characteristic that is sorely lacking from the US political class.

The US Political Class is made up of Gullible people unable to do their own research because that is what the system has incentivized electing People with intelligence, principles, and convictions rarely last long in politics; People lacking those skills but the ability to charismatically reiterate the talking points of politically connected charities, action groups or lobbiest are well sought after....

A more optimistic interpretation of "The US Political Class is made up of Gullible people unable to do their own research because that is what the system has incentivized electing" would be that the US political class can't possibly do their own research on every topic that they have to govern and instead have to rely on external experts. Not arguing that it ends up being those with the most money being the loudest, but it makes sense that you'd want to use the research of others for your own decision making if you're not an expert and have access to experts.

Re: Heat pump disappointment for climate-minded Massachusetts state senator

#84

Post by dahfizz »

kkfx wrote: post #79
dahfizz wrote: post #38

Earlier quoted context omitted.

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 stov…

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.

Re: Heat pump disappointment for climate-minded Massachusetts state senator

#85

Post by trey-jones »

SketchySeaBeast wrote: post #82
trey-jones wrote: post #57

Earlier quoted context omitted.

I have two self-installed ground source heatpump units (6 tons total) in operation since summer of 2016 with no maintenance except for the loop pump. I was using two very old second-hand pumps until last summer (one for each unit), when one impeller completely disintegrated. I took the opportunity to reconfigure the plumbing and wiring a little bit to use only one pump (more modern, theoretically better fit for my sy…

How deep are your lines buried? Did you need to be concerned about the frost line?

My ditch was 8 ft. which I believe would be considered overkill. I'm also not worried about freezing at all (GA, USA). My system does more work in the summer than the winter.

Re: Heat pump disappointment for climate-minded Massachusetts state senator

#86

Post by falcolas »

olivierlacan wrote: post #80
falcolas wrote: post #47

Earlier quoted context omitted.

Bad assumption. It’s like expecting framers to know the ins and outs of LVL production. They’re there to put widget A in widget B, according to the instructions.

That's a fairly inappropriate comparison in level of expertise necessary to design a system: LVL beams are picked by structural engineers, not by framers who generally install them where they're needed, based on a structural design which they have no say in because load calculations aren't a framer's job. HVAC installers are not merely system assembly specialists, they're system design specialists as well in nearly a…

As someone who recently had a heat pump installed, your expectations for minimum wage workers is rather unrealistic. We asked for one, they estimated the cost and installed it, and we paid the bill.

It was their second installation, ever. Red state with lots of gas installations and all that.

The onus of understanding that it wouldn’t work under a certain temperature, and would get lower in efficiency the lower the temperature, was on me.

It wasn’t that hard to understand, either.

Re: Heat pump disappointment for climate-minded Massachusetts state senator

#87

Post by throwaway4aday »

endisneigh wrote: post #70
throwaway4aday wrote: post #63

Earlier quoted context omitted.

I'm a bit confused since I thought you were talking about hooking up a wood fired furnace of some type. Putting a solid fuel boiler in line with an existing system is pretty common and doesn't have any impact on the system as a whole efficiency wise except for a tiny bit of heat lost to the length of pipe in the boiler when it's not in use but if you don't mind turning valves on and off you can avoid that with some s…

my understanding is that a wood furnace is meant to be used with wood pellets or properly seasoned wood. using random rotting decaying dead wood outside probably wouldn't be a great idea - I'll need to look into it more.

Ok, yes that's true, if you burn wet, green or rotten wood it's going to make a lot of smoke. Wood really begins to rot after the first year if it isn't cut, split and properly dried. If you have deadfall around you that you want to use then you need to process it into firewood as quickly as possible and store it somewhere it won't stay wet.

Re: Heat pump disappointment for climate-minded Massachusetts state senator

#88

Post by c4mpute »

matheweis wrote: post #77
c4mpute wrote: post #42

Earlier quoted context omitted.

I'm not sure if you will ever see that, the EU is currently trying to band all flourinated hydrocarbons, right in the middle of the 'we all need a heatpump' run. The only "viable" refrigerants after that will be CO_2, propane and ammonia. The "viable" is in scare-quotes because all of them are kind of nasty, CO_2 and ammonia are quite poisonous, CO_2 is inefficient or unusable for the temperature range in question, a…

Is propane that bad? We have propane plumbed throughout houses everywhere here in the us, and while accidents happen they are extremely rare. I would think that with a closed loop system the risk of a serious problem would be quite low.

The pressure is higher in A/C and heat pumps, and you have liquid propane in half of the system. A leak there will quickly create a huge volume of flammable propane-air-mixture at room pressure. The usual plumbing for heating and cooking is at a very low (over-)pressure, 100mbar or something, and your distribution network in town is typically at 1bar. A leak there is less bad and will take some time to fill up space with enough flammable propane-air-mixture to be dangerous, enough time to maybe sound an alarm and evacuate. Generally, a basement full will obliterate the occasional building in any case.

Re: Heat pump disappointment for climate-minded Massachusetts state senator

#89

Post by red-iron-pine »

phpisthebest wrote: post #4
tgflynn wrote: post #2

It's good to see a politician actually doing their own analysis rather than just following every fad. It's a characteristic that is sorely lacking from the US political class.

The US Political Class is made up of Gullible people unable to do their own research because that is what the system has incentivized electing People with intelligence, principles, and convictions rarely last long in politics; People lacking those skills but the ability to charismatically reiterate the talking points of politically connected charities, action groups or lobbiest are well sought after....

They're not "gullible" -- they exist to flog the views of those who elected them; that's their job. They exist to be a sock puppet for their voters.

Think tanks exist to come up with policy prescriptions. There are just so many topics, internationally, locally, nationally, that no one can be a deep-dive expert unless they focus specifically on it.

Re: Heat pump disappointment for climate-minded Massachusetts state senator

#90

Post by osigurdson »

tcfhgj wrote: post #62
osigurdson wrote: post #44

Earlier quoted context omitted.

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.
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