EV-based road transportation is not viable

[tszaboo]

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.

Heat is heat. There is no difference for heat pump heat or heat from a boiler or gas.

[mikeselectricstuff]

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.

Heat is heat. There is no difference for heat pump heat or heat from a boiler or gas.

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.

[nctnico]

Yeah, people who are not into this field don't realize this. You can store enough energy in a 0201 capacitor, that shorting out this capacitor would create a tiny spark that can set hydrogen on fire. It's very very explosive, odorless, and the storage conditions are crazy compared to propane for example.
It can literally go through steel for example due to the small atoms, and crack it in the process (called hydrogen embrittlement). When they talk about adding it to regular district heating, I really hope they know what they are doing, because it would be a disaster, if pipes of the gas network would wear out and break.

Again: the gas made from coal contained lots of hydrogen and was transported through steel pipes without problems. Embrittlement only happens at special conditions. Hydrogen is not something new. Secondly, most natural gas infrastructure is made from hydrogen compatible 'plastic' and joints. Yeah, people who are not into this field don't realize this.

It is all about conditions...

[tszaboo]

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.

Heat is heat. There is no difference for heat pump heat or heat from a boiler or gas.

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.

If it works for Norway, there is really no reason why it wouldn't work for the UK or here.

[nctnico]

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.

Heat is heat. There is no difference for heat pump heat or heat from a boiler or gas.

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.

If it works for Norway, there is really no reason why it wouldn't work for the UK or here.

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.

[Marco]

Flamability range:

Detonation has far worse effects than deflagration.

[bdunham7]

Heat is heat. There is no difference for heat pump heat or heat from a boiler or gas.

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...

[TimFox]

Heat is heat. There is no difference for heat pump heat or heat from a boiler or gas.

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...

To heat the interior of your house to 23^o C when the outside temperature is, say, 10^o C requires delivery of hot air at a temperature above 24^o C, even with reasonable wall insulation.

[bookaboo]

I don't have a horse in the heat pump debate but found this interesting in the "against" column:

[Marco]

heat pumps don't produce the higher temperatures needed to overcome poor insulation.

That depends a bit on what you use for heating. Floor/wall/ceiling hydronic heating can dump much larger amounts of heat into a home at a given water temperature than high temperature radiators, though that's a more involved retrofit (with floating laminate floors it's a relatively easy retrofit though, just raises the floor a tiny bit).

What is almost always an easy retrofit are Fan Coil Units, with the added advantage that they give you cooling too. I'm amazed no installers are specializing in this, it's such a perfect package.

[TimFox]

Recently, my undergraduate college replaced their traditional central boiler with a heat pump, heat-sunk to a subterranean layer of ground water at approximately 13^o C in the middle of the local seasonal temperature range (roughly -30^o C to +35^o C, a continental climate in southern Minnesota).
I'm not sure how much they use this for summer cooling.

[nctnico]

What is almost always an easy retrofit are Fan Coil Units, with the added advantage that they give you cooling too. I'm amazed no installers are specializing in this, it's such a perfect package.

Fan noise? Mechanical parts that can fail? I also have serious doubts about the ability of installers of heating systems to be able to understand how to install these units properly. Look at the huge amount of aftermarket devices you can buy for underfloor heating to -for example- stop the pump when the heating is off. Something simple like that should come standard with any underfloor heating system.

[coppice]

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.

You only need higher temperatures to overcome high heat losses if you use convection alone. A little fanning goes a long way.

[Marco]

Fan noise? Mechanical parts that can fail?

Sure, it has its downsides. The fact it comes with cooling too is a huge upside though. Lots of people using splits for heating/cooling too.

I also have serious doubts about the ability of installers of heating systems to be able to understand how to install these units properly.

That's why I said specialise. If one install in a hundred has FCUs, sure it will be a mess. If they do 5 in a week, it shouldn't take them too long to find out how to prevent complaints and return visits.

[Ice-Tea]

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.

Heat is heat. There is no difference for heat pump heat or heat from a boiler or gas.

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.

If it works for Norway, there is really no reason why it wouldn't work for the UK or here.

And the diagram is horribly optimistic where it comes to the efficiency.

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).

At low temperatures the heat pumps will have to go into resistive heating mode requiring the original 70GW.

I think perhaps you're working with an outdated set of information on heatpumps.

And what happens if the turbines don't spin?

Well, that's an interesting question for any discussion on renewables but for fun and giggles: with a COP of 4 you'd still only burn half the gas in an electricity plant compared to your house boiler.

Bottom line: the diagram is made by a complete idiot. 

In that case a lot of people are complete idiots because it pretty much represents the consensus amongst energy scientists. Yes, putting the windmills as energy source in the picture is a bit rosy but that doesn't change the bottom line.

[themadhippy]

most natural gas infrastructure is made from hydrogen compatible 'plastic' and joints. Yeah, people who are not into this field don't realize this.

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]

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.

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]

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.

Heat is heat. There is no difference for heat pump heat or heat from a boiler or gas.

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.

If it works for Norway, there is really no reason why it wouldn't work for the UK or here.

And the diagram is horribly optimistic where it comes to the efficiency.

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).

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]

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.

Heat is heat. There is no difference for heat pump heat or heat from a boiler or gas.

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.

If it works for Norway, there is really no reason why it wouldn't work for the UK or here.

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.

Typical winter with this climate, the deltaT is 20-30, entirely possible to provide this even with air source heatpump.

Heat is heat. There is no difference for heat pump heat or heat from a boiler or gas.

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...

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.

[nctnico]

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.

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

One of my relatives is an advisor for people who seek to improve the insulation & lower the carbon footprint of their homes. His conclusion is that it is not worthwhile to re-insulate older homes because the basic structure doesn't allow for it. Better insulation also means adding air treatment to manage the moisture inside a home which means adding ducts and mechanical ventilation. So the only option is to use hybrid heaters (heatpump + boiler) in order to get enough heat into such homes. Heating is not just necessary to keep the people inside a home warm, but also to keep the home itself dry in order not to get problems with mold and wood rot. It is pretty complicated to get right from the start. Let alone trying to do a retrofit.

[nctnico]

Look up "SCOP".

Did that. It is a meaningless number. Just like NEDC / WLTP for cars. It doesn't tell you anything about the actual performance.

[Marco]

And external insulation is very easy to get badly wrong

Meh, moisture problems from barrier effects tend to be overblown. If they screw up badly enough blown rain can get behind the insulation it's because they are half assing it, not because it's difficult.

The main problem with external insulation is that it's bloody expensive still. They need some kind of system which just 3D scans the external walls and gives the workmen a bunch of legoblocks to fill it with in a day.

[Ice-Tea]

So, uhm, that's your argument then? You disregard any data that doesn't fit your narrative and call all those that run with it idiots? 

[nctnico]

Typical winter with this climate, the deltaT is 20-30, entirely possible to provide this even with air source heatpump.

It is not about the temperature delta, but the absolute temperature operating range of a heatpump! And at some point the outside unit will ice up preventing extracting heat from the environment. The graph you posted is way too optimistic. A heatpump simply does not work well in a climate that has close to or sub-zero temperatures.