Never mind the EVCPs, what about the boilers.

I belive the UK government is only planning on banning new gas installs for the time being.  The UK housing stock isn't really ready for wholesale conversion to heat pumps without first spending a lot of money on insulation.  So far, the governments initiatives to insulate housing better have been shambolic and largely unsuccessful.


Switching to an electric car could well double the electricity usage of a household, but that doesn't mean it applies to the country as a whole.  Driving an electric vehicle to work won't suddenly double the electricity consumption of the office or factory you're working at.

(According to OVO energy, the typical electricity usage of a house is around 3 to 4 MWh a year, depending on the size of the house.  Driving an electric vehicle 10000 miles would take perhaps 3.3MWh, assuming 3 miles per kWh)

Yes, the ban on new buildings with gas  boilers is already scheduled to come into effect in 3 1/2 years time.


Couple that to red diesel vanishing as an option for heating  commercial buildings  and  generator fuel next year, and we can look forward to higher electrical demand. ( domestic use of oil heating remains on the low tax rate for for now, but place your bets as to what may happen next)


However the proposals from Faith Birol at the International Energy Agency (IEA), basically extend that to cover no new fossil fuel boilers of any kind  should be sold from 2025. 

If that proposal gets adopted by governments then that is a different matter, as in effect all current installations would be on a ticking clock until available  spares run out.

I'm inclined to agree that is a very brave target to propose.

Especially given that we have a lot of hundred  year old or older housing stock that leaks heat from every pore and we have not managed to fix that at any time in the last 50 years or so. Things take far longer. After all, there is plenty of single glazing still in use, and double glazing has been de-facto since the 1970s oil crisis, and a building regs requirement when replacing windows for a touch over 20 years. There a whole housing estates with 1950s solid wall housing that cannot be cavity filled (not that it stops salesmen ringing up to try and sell it of course.)


If we started with 'negawatts'  by designing houses that are insulated and have a larger volume so the surface to volume ratio is more favourable, that would be a start, and upgrading the older ones to a less 'leaky' standard. So far this has been pretty poor all round.

The disconnection between the airy aspiration, and the state on the ground is remarkable, and at some point reality will bite.


And yes there are not enough kVa either.

Mike.

In my view the current Building Standards are not adequate with regards to insulation and poor build quality make them even worse. A friend did some work on a relatively new house and found a wall with no insulation in it, he complained to the developers who replied someone must have stolen it after it was built!


If we are to achieve a reduction in power usage we must insulated our old housing stock, which is very expensive, and build new houses to an adequate standard. Unfortunately the various government schemes devised to improve insulation appear to be ill-conceived  opportunities for the scammer to make money.


Never mind:  Hydrogen, wind mills and solar power will sort it all out.

District heating would help significantly, but someone has to invest in digging up streets for pipework, etc., again this is easier for new-builds. I happen to live in a UK city with a (small) heat network, but they are rare here compared to other countries.


Currently (2pm Friday) we are generating 13.6 GW of electricity (41% of current demand) in thermal power stations which implies we are dumping around 35 GW of heat into rivers, various areas of shallow sea, and cooling towers. That is heat that could be delivered to buildings in towns and cities near those plants.

Whilst the use of heat rejected from power stations sounds attractive and is regularly proposed, it seldom makes economic or engineering sense.

A modern power station rejects heat at very low temperatures, often less than blood heat. This is too low for domestic or similar heating. The volumes of only slightly warmed water needed would be vast as would be the energy used in pumping this water.

Water at such low temperatures requires either heated floors, or improbably sized radiators to transfer enough heat into the rooms.


Heated bathing pools are a possibility, but how many of those do we need ? Thermal desalination of seawater is another possibility, but demand is limited.

If one does use this heat, it reduces the power station efficiency considerably. This is why we use cooling towers, the turbines must exhaust into a fairly good vacuum from condensing the steam. CHP is nothing like as wonderful as it is often made out to be, you should see the steam leaks in New York on a cold day!


Unfortunately, Richard, the air temperature over a lot of Britain in winter is much less than zero, at -10 to 60C the heat pump is not a lot of use, Electricity costing about 5 times as much as gas, from my latest fuel Bill. Heat pumps only work where the transfer is air to air, ie. full air conditioning, as I pointed out the other day elsewhere on the forum.

Ground source heat pumps are a thing.  One option is to dig up the lawn and bury a long coiled hosepipe ("slinky") under it.  The other option for people with smaller gardens is to drill a number of deep boreholes.  Either way, this allows you to suck heat out of the ground during the winter, allowing it to recover in the summer.  But it's expensive and/or disruptive to install.  And if you make the ground source too small, the ground will eventually freeze solid, and the COP will plummet.


Water source heat pumps also exist, but are only an option of you have a river at the bottom of your garden.  One National Trust house saved a fortune replacing the old boilers with heat pumps that suck heat from a handy river.

Thermal power station coolant outputs are generally in the 30-40 C range, this is warm enough to be useable as an input to a heat pump and hugely increase its COP compared to ground source or especially air source.


If you wanted to directly use the heat for say underfloor heating you might prefer a higher temperature which would come at the expense of a modest decrease in thermal efficiency for the electricity generation. Say you raised the coolant outlet from 35C to 50C, and for the sake of argument assume the hot side is a PWR at 275 C. We've lowered the theoretical efficiency from 44% to 41%. For the same thermal input the plant has lost around 5% of its electrical output but now produces usable heat sufficient for many thousands of buildings which then no longer need to be electrically heated. You can still have a net win here.

I feel that we are being herded onto the most expensive source of energy of all, especially for heating purposes. Electric heating is effectively being forced upon those in our society who can least afford to pay for it. It's the same with electric cars. Studies have shown that those at the bottom of the pile who can just about afford to run a rusty Renault will never be able to afford an electric car.

So unless Greta puts her hand in her very full pocket this will have a very adverse effect upon the electoral chances of any Govt which attempts to vigorously pursue it to the bitter end rather than just fly a kite for focus group purposes. I rather suspect and fervently hope that Boris is just blathering and blustering and is about as serious about this nonsense as he is about redecorating the flat in No 10.


Politics aside, once the electric car charger brigade have chomped off their share of our existing generating capacity, just where is the capacity going to come from to feed all of these snake oil heat pumps?


The incongruity  knows no bounds - a ground source heat pump - according to a rich neighbour of mine who markets such systems exclusively in the USA - states that for every quid spend on electric juice gets you four quid back. To me, there is never ever something for nothing, yet the supposedly smart degree-qualified chattering classes are going mad for these things. When I tried to highlight the fag packet economics behind it and that gas central heating was much cheaper, they said that gas was going to rise in price so they would be better off going the heat pump route, yet when I highlighted the fact that much of the UK's electricity is generated by gas fired power stations you could just about hear the tumbleweed blowing past............