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| themadhippy:
--- Quote ---most natural gas infrastructure is made from hydrogen compatible 'plastic' and joints. Yeah, people who are not into this field don't realize this. --- End quote --- whilst the main pipe work maybe plastic,in the uk at least ,often the final connection to the meter is a flexible metal pipe and from the meter to boiler/cooker,copper or in older propertys iron.Could be fun times ahead. |
| tggzzz:
--- Quote from: tom66 on February 21, 2023, 03:48:28 pm ---Good diagram. But, does it account for the difficulty in insulating UK homes to support heat pumps? Having embarked upon the process of insulating our 1930's detached home, it is definitely not a trivial process usually requiring bespoke techniques for each property. --- End quote --- And external insulation is very easy to get badly wrong, e.g. https://www.walesonline.co.uk/news/wales-news/victims-home-insulation-scandal-scandal-26076372.amp Somewhere there's a report on the faults, and it isn't pretty. |
| nctnico:
--- Quote from: Ice-Tea on February 21, 2023, 05:57:45 pm --- --- Quote from: nctnico on February 21, 2023, 04:13:36 pm --- --- Quote from: tszaboo on February 21, 2023, 04:13:00 pm --- --- Quote from: mikeselectricstuff on February 21, 2023, 04:10:48 pm --- --- Quote from: tszaboo on February 21, 2023, 03:57:36 pm --- --- Quote from: tom66 on February 21, 2023, 03:48:28 pm ---Good diagram. But, does it account for the difficulty in insulating UK homes to support heat pumps? Having embarked upon the process of insulating our 1930's detached home, it is definitely not a trivial process usually requiring bespoke techniques for each property. --- End quote --- Heat is heat. There is no difference for heat pump heat or heat from a boiler or gas. --- End quote --- Not true. optimum working temperature is different between different systems - heat pumps don't produce the higher temperatures needed to overcome poor insulation. Replacing a traditional pumped water/gas CH system with HP usually requires radiators to be up-sized to get the same output at a lower temperature drop. --- End quote --- If it works for Norway, there is really no reason why it wouldn't work for the UK or here. --- End quote --- And the diagram is horribly optimistic where it comes to the efficiency. --- End quote --- Why??? A well insulated house allows for a SCOP of 4.5 or so. Badly insulated houses obviously need to get moving on improving that but would still allows for a 3+ SCOP (with fan trays or whatever). --- End quote --- Simple: the COP of a heatpump depends greatly on the outside and inside temperature. The listed COP is an optimum, not a minimum. Last year I installed a brand new airco / heater system from Panasonic (IOW: not some shoddy B-brand). The specified COP for heating is 4.6. You'd say that is great but the service manual comes with pages of tables with the cooling and heating capacity (input versus output power). When the outside temperature gets below 0 degrees, the COP drops below 2. |
| tszaboo:
--- Quote from: nctnico on February 21, 2023, 04:13:36 pm --- --- Quote from: tszaboo on February 21, 2023, 04:13:00 pm --- --- Quote from: mikeselectricstuff on February 21, 2023, 04:10:48 pm --- --- Quote from: tszaboo on February 21, 2023, 03:57:36 pm --- --- Quote from: tom66 on February 21, 2023, 03:48:28 pm ---Good diagram. But, does it account for the difficulty in insulating UK homes to support heat pumps? Having embarked upon the process of insulating our 1930's detached home, it is definitely not a trivial process usually requiring bespoke techniques for each property. --- End quote --- Heat is heat. There is no difference for heat pump heat or heat from a boiler or gas. --- End quote --- Not true. optimum working temperature is different between different systems - heat pumps don't produce the higher temperatures needed to overcome poor insulation. Replacing a traditional pumped water/gas CH system with HP usually requires radiators to be up-sized to get the same output at a lower temperature drop. --- End quote --- If it works for Norway, there is really no reason why it wouldn't work for the UK or here. --- End quote --- The key word here is: insulation And the diagram is horribly optimistic where it comes to the efficiency. At low temperatures the heat pumps will have to go into resistive heating mode requiring the original 70GW. And what happens if the turbines don't spin? Bottom line: the diagram is made by a complete idiot. What will work is using hybrid heatpump boilers. These use their heatpump only when the COP is positive and the burner to give a boost when it is really cold. Hydrogen provides electricity, storage and fuel. --- End quote --- Typical winter with this climate, the deltaT is 20-30, entirely possible to provide this even with air source heatpump. --- Quote from: bdunham7 on February 21, 2023, 04:31:52 pm --- --- Quote from: tszaboo on February 21, 2023, 03:57:36 pm ---Heat is heat. There is no difference for heat pump heat or heat from a boiler or gas. --- End quote --- Imagine the outside temperature is 0C and you want to heat your house to 23C. I supply you with an unlimited amount of water at 24C. Can you heat your house with that? After all, you have infinite heat available... --- End quote --- Yes, a spherical 1m diameter cow is floating in outer space, and a constant 1000A current is flowing into it on a tiny wire, what's going to be the voltage of the cow, and which way is is going to move from earth at what speed? |
| Ice-Tea:
Look up "SCOP". EDIT: also, I assume this is an air/air unit. Not exactly apples to apples. |
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