Most CO2 refrigeration systems in the US are referred to as “transcritical” but don’t ask me to define that.

Isn't plasma where electrons and atoms have separated and no longer associated? Like whats found in the sun and lightning?

Use of word ' Plasma' sounded a little weird but if it helps people to understand the concept then why not?......basically it's the starte of the refrigerant that. Is most efficient for CO2 heat pumps

This video needs a lead up explanatory to explain the abbreviations used.

air src heat pumps in a moist uk environment? No chance. Please provide numbers showing how often then de-icing cycle is triggered. Typical home needs 20MWh/annum to heat and you want to load up the electric Grid to take on that load with British homes? Utter overload. ashp would average cop of 1.4 if you're honest. Grid losses mean that to get 1kwh of power into your home it costs 3kWh of energy from the nuclear power plant which is disastrous. Electrical power should not be squandered on heat, just used for electronics! Then the lib idiots think that nuclear is clean because it involves little CO2... go swim in the waste pools at Sellafield then. They will be festering for the next ten thousand years with lethal radiation, just because some idiot in 2024 decided to heat their conservatory from a heat pump. Nice inheritance for your your grandkids huh? Are we collectively losing our minds? Nuclear Power - No, thank you. It was true in the '70s and is still true today. Solar thermal and wood logs, loads of natural insulation with gas/oil backup is the way to go.

This model is great for heating your hot water but not so great at heating your home

@@danielwebb2773 - the technology is there already..it will be utilised for space heating with additional controls, it might be a case of buffer and then drawing from that buffer onto your specific heat exchanger

@@kevinfleming9770 The Japanese have a range of "eco-cute" (a Japanese marketing thing, it seems) CO2-based DHW heat pumps, one of which by Sanden has seen a small number of installs here in the US, including one (two? - have to ask again) by my favorite installer. It can be made to work as you describe, but the CO2 is run at over 1,000 PSI which requires higher quality of construction which increases cost - that is the short term problem as it can't compete. Maybe if we get into using thermal buffers to effect time-shifting of electricity use as an additional value stream it could come into focus, but R-290 monobloc seems a shorter path to the same no-more-GWP-worries end from where I sit.

Yea

@@HeatGeek Thank you for answering. I do appreciate the struggle to inform the general public you are undertaking. Keep it up. Cheers.

The 40% efficiency 'limitation' is the theoretical limit of a closed Carnot Cycle within a thermal power station, ie. that of power stations with cooling towers that need to condense dry stream from the turbine exhaust back to liquid water for the feed pumps to inject it back into the boiler. This is applicable to nuclear, biomass and coal stations. Gas power stations use a different process - combined cycle gas turbine (CCGT) plant which uses the combustion products to directly spin the turbines. This has a much higher theoretical efficiency, and the exhaust then used for a regular thermal cycle. Gas -> CGGT -> Electricity -> Grid -> Heat pump is both theoretically and practically more efficient than burning gas on small scale domestic boilers.

You do! The rest of them are just few and far between in my 20 years experience! Hope your well!

Couldn’t agree more with the “cut & paste” comment. I worked with consultants a lot 15 years ago and I’ve just started working with them again; and nothing has changed. Over-engineered and over-powered with lots of mistakes in the specification with very little flexibility when you ask for changes.

Need to find you first, you are very rare

R290 is propane

@@dinendale666 Yes, I should have interpreted that: specifically the gas one burns is about 90% propane (hopefully) and r-290 is held to a higher standard, I believe at least 95% propane. R-600a is iso-butane and is now used in almost all residential refrigerators and freezers legally for sale in New York State US for example, while R-290 high-purity propane is now found in most (not all) commercial refrigerators and reach-in freezers - some penetration in larger units, also modular units for grocery that are an alternative to "rack" systems based on CO2.

@@tomkacandes8286 yes , R-290 is specified as nitrogen free . I know it’s not the LPG you use in blow touches.

@@dinendale666 Another good detail, thank you. I was not correcting you, but other people watching or reading comments might not appreciate how R-600a is more specific and pure than what you get in a lighter-refill can or R-290 is not what you get for your bar-B-que. If you think Heat Geeks are a rare breed, chat about refrigerants to even people promoting heat pumps and you'll find not so many folks understanding much about GWP from refrigerants for example, lol.

Having the odd day of coal doesn't mean all the renewable electricity is all of a sudden dirtier.. we're a decade late imo!

I have had to prioritise solar and batteries here in Halifax. We have a mix of gas and electric underfloor but the ASHP for this bigger house is just so expensive, especially with new underfloor the returns are going to be very very slow. Solar could pay for itself in as little as five years.

That is not actually true in terms of Global Warming Potential: R-290 and R-600a have one fifth the GWP (less than 0.2 vs. 1) than CO2. Source is IPCC AR6 report which recalibrated the GWP of these down from 3 before. Also, ammonia is toxic, the others are not.