Electric everything.

[[XAP]Bob]

Not having appropriately sized radiators isn't a heat pump problem - although it is more noticeable at that point. Of course the real answer is to run the heat pump for longer, at an even lower power input.

No, the answer is to fit larger radiators, improve insulation, or run the heating circuit at a higher temperature. If the radiator can't supply heat faster than it leaks from the room, it doesn't matter how long you run the pump for.

I was assuming that the radiators weren't borrower sized and that the door wasn't left open in the shed.

[al_yrpal]

Well Mr Kwateng put his foot in it with his "heat pumps are that much worse than boilers" statement. An unqualified statement by an unqualified bloke. But...there is probably some truth there. Like early solar panel installations many are likely to be faulty in various fashions. Radiators being too small in gas or oil to heat pump conversion situations for a start. Powered by electricity generated largely from fossil fuels another. Confusing coefficient of performance with efficuency yet another.
However we have to start somewhere. If someone is prepared to finance digging up a huge section of my lawn and reinstating it to install a ground source I'll be there with my begging bowl.

Al

Frankly even a mediocre heat pump can push more heat into a house than a perfect boiler given the same amount of gas to start with (because the gas being burnt in a power station is multiplied by the heat pump coefficient).

Not having appropriately sized radiators isn't a heat pump problem - although it is more noticeable at that point. Of course the real answer is to run the heat pump for longer, at an even lower power input.

Sorry Bob, thats exactly what inexperienced installers think and lots of them are getting it wrong.55 degrees C doesnt hack it.

Al

[[XAP]Bob]

I disagree - too small radiators will need to be replaced, but that isn’t a heat pump problem.

[al_yrpal]

I disagree - too small radiators will need to be replaced, but that isn’t a heat pump problem.

No it isnt, but it is a very common problem because plumbers are installing these things straight into houses that once had gas or oil boilers without enlarging the rads. And, these things arent as green as is being asserted because they are powered substantially by fossil fuels just like electric cars.

Al

[Manc33]

Not if everyone's charging their car at night (fast forwarding 30 years)

It's all fuzzy... "everyone" isn't going to happen, 'night" isn't a constant, and change will come gradually.

Oh, I don't know. "Everyone" goes to the petrol station to fill their cars with petrol at exactly the same time, don't they?

It doesn't take "6 to 12 hours" (Tesla) to fill up with petrol though, it takes 2 minutes using the pump.

Night time would be the only time people could charge it, or when they are at work.

There would be a lot more electricity being used from 9AM to 3PM as everyone charging at work plugs in for 6+ hours and a lot more being used at 6PM to 12AM for people charging at home.

The power it takes to charge a Tesla Model S (100 kWh) is equal to running a kettle non stop for 40 hours.

I never worked it out before but those Tesla cost about 6p per mile to run, no wonder people are buying them!

[jb]

I disagree - too small radiators will need to be replaced, but that isn’t a heat pump problem.

No it isnt, but it is a very common problem because plumbers are installing these things straight into houses that once had gas or oil boilers without enlarging the rads. And, these things arent as green as is being asserted because they are powered substantially by fossil fuels just like electric cars.

Al

The difference being that as the grid gets greener and as gas and coal dwindle, then anything electric powered gets greener with it. Also it happens without the owner having to do anything.

[Mark R]

There is a very interesting primer on currently available heat pump tech from the most excellent "Fully Charged Show" (but they don't say too much about noise)

In optimal conditions these systems can deliver 5kw of heat for 1 kw of electical input

https://www.youtube.com/watch?v=a63HkWetENk

I think the "heat battery" will become one of the go-to solutions for retrofits.

[Jdsk]

And, these things arent as green as is being asserted because they are powered substantially by fossil fuels just like electric cars.

The difference being that as the grid gets greener and as gas and coal dwindle, then anything electric powered gets greener with it. Also it happens without the owner having to do anything.

Yes.

Jonathan

[Jdsk]

It's all fuzzy... "everyone" isn't going to happen, 'night" isn't a constant, and change will come gradually.

Oh, I don't know. "Everyone" goes to the petrol station to fill their cars with petrol at exactly the same time, don't they?

It doesn't take "6 to 12 hours" (Tesla) to fill up with petrol though, it takes 2 minutes using the pump.

Night time would be the only time people could charge it, or when they are at work.

There would be a lot more electricity being used from 9AM to 3PM as everyone charging at work plugs in for 6+ hours and a lot more being used at 6PM to 12AM for people charging at home.

The power it takes to charge a Tesla Model S (100 kWh) is equal to running a kettle non stop for 40 hours.

Of course it's going to vary enormously ... but roughly how many hours a day (or week) on average do you expect an EV will need to be charged?

Thanks

Jonathan

[[XAP]Bob]

It doesn't take "6 to 12 hours" (Tesla) to fill up with petrol though, it takes 2 minutes using the pump.

Night time would be the only time people could charge it, or when they are at work.

There would be a lot more electricity being used from 9AM to 3PM as everyone charging at work plugs in for 6+ hours and a lot more being used at 6PM to 12AM for people charging at home.

The power it takes to charge a Tesla Model S (100 kWh) is equal to running a kettle non stop for 40 hours.

I never worked it out before but those Tesla cost about 6p per mile to run, no wonder people are buying them!

I've never managed to fill a car in two minutes, certainly not from arriving at (and therefore blocking) the pump to leaving (and therefore making it available for the next user). Five is a more reasonable estimate.

Also... a typical car in the UK does 20 miles per day, that's 4kWh (or 5 if you use my more usual 4m/kWh efficiency rating). That's about half an hour to 45 minutes at a slow home charger.

It's just not a load that the grid will have any issue supplying - particularly since you don't charge at 6pm, you delay the start of the charge to the time when electricity is cheapest (i.e. the middle of the night, when the grid needs more electricity to be being used).

As for your costings... a Tesla will quite happily get 5+ miles per kWh, and it's relatively easy to get a 5p tariff overnight (hint that's because the grid is under-utilised at night, and we have masses of spare capacity) so that's 1p/mile, not 6 - I've no idea where you got that from, unless you are assuming that you can only use the public charging networks (hint no-one is in that position).

Even if you pay 30p/kWh (typical contactless public charger rate, range I've used (ignoring free vends) is 25-35p) then you are hitting 6p/mile, as opposed to the current ~£6/gallon giving a cost of ~15p/mile for a decent 40mpg real world average vehicle.
And that's only ever the case after the first substantial leg of any journey - most people only ever need public charging for a handful of journeys a year, even if it got up to price parity with petrol it would still be cheaper to run electric.


What's interesting to me is how much difference a few small solar panels could make.
There is easily space for ~3m^2 of panels (one on the bonnet, two on the roof) for about ~600W nominal and in typical UK conditions that would be ~420-540kWh. That's ~ two to two and half thousand miles, or nearly a third of all the power needed for a typical UK car.
Obviously that would be variable, giving more in the summer than the winter, and it would also require the car to be outside (not in a garage or multi-storey car park). The estimate is also almost certainly inflated by the likely angle of the car at any given time (assuming an average of being level, then we lose an additional ~30% ish (eyeballing it))
If a vehicle could get its own power for even a quarter of the miles it does... that's huge.

[[XAP]Bob]

I disagree - too small radiators will need to be replaced, but that isn’t a heat pump problem.

No it isnt, but it is a very common problem because plumbers are installing these things straight into houses that once had gas or oil boilers without enlarging the rads. And, these things arent as green as is being asserted because they are powered substantially by fossil fuels just like electric cars.

Al

Well that rather depends on how you get your electricity.

Even with a gas power plant - you get more heat energy out of the gas by burning it at a power plant then moving the power down wires and powering a heat pump than you would by just burning it at the end location. And because you have a large single burner it can be very well controlled it doesn't start/stop constantly through the day and it will be significantly less polluting than all the separate boilers would be. It's also relatively easy to install scrubbing technology to the one big chimney.

And of course it's trivial to power using local micro generation, or to run it when the grid is greenest, or to buy power from renewable suppliers.
As the grid decarbonises... then you get the benefits "for free", you don't need to replace your boiler with a hydrogen compatible model, the heat pump doesn't care how the electrons were energised, just that they were.

[mjr]

Well Mr Kwateng put his foot in it with his "heat pumps are that much worse than boilers" statement. An unqualified statement by an unqualified bloke.

Him, or you? His actual statement was "I don't think actually heat pumps are that much worse than boilers. All I'm saying is that they could be improved if there was more investment."

But...there is probably some truth there. Like early solar panel installations many are likely to be faulty in various fashions.

Early?!? Early heat pumps date from the 1840s. Anyone still installing those should be struck off whatever approvals lists! Norwich City Council were heating some of its buildings with one in the 1940s.

It feels a bit like the Pendolino all over again: a technology that is good for the UK which we had a leading role in developing (APT-P and APT-E) and then ignored and let others develop to the point where we import the finished things from abroad — with heat pumps, it's companies like Mitsubishi and Daikin (who have only been making them since the 1950s so of course these are all teething troubles with the technology and not inexperienced UK installers(!)). Hopefully, it won't continue like the Pendolino story where we don't simply order a second generation from experienced manufacturers, but instead try a half-cock version from another company with a UK factory (but they end up building them abroad!), then remove the innovative bit to reduce maintenance costs, and then finally revert to older technology because some company opens a factory in northern England!

[Jdsk]

Electric cars can be charged at night, when there's bags of surplus capacity.

Not if everyone's charging their car at night (fast forwarding 30 years)

It's all fuzzy... "everyone" isn't going to happen, "night" isn't a constant, and change will come gradually.

But:

1 Many of the desirable sources of electric power are intermittent. And with variable degrees of predictability... solar, tidal, wind.

2 EVs spend a lot of their time sitting still.

3 Current (!) EVs only need to be recharged for a small part of that time.

So choosing when to recharge EVs can reduce that problem of intermittent generation. That means that you don't have to build so much capacity.

Taking that a stage further the batteries in EVs can be used to feed power to the grid. That means that you don't have to build so much of other types of storage.

Of course this requires a financial system that gets the incentives right. And even the simple step of smart meters hasn't gone well in the UK.

For vehicle-to-grid it also require that the effect on the EVs' batteries is acceptable. There aren't any warning signs appearing on this, but it's a bit early to see if it will affect the useful life of the battery and possibly of the car.

Ofgem priorities announced, including vehicle to grid:
https://www.ofgem.gov.uk/publications/o ... -consumers

Our priorities will ensure electric vehicle (EV) rollout unlocks full benefits for consumers and the environment, and reduces the cost of the energy system.
Adopting smart charging and vehicle-to-grid technology will help keep bills lower over time for consumers.
Proposals will bring down costs of installing new electric vehicle charge points where they are most needed.

Jonathan

[jb]

Of course a sensible government would go for a standard set of chargers all with the same payment system. A bit like petrol pumps are all basically the all the same.
And of course that won't happen...

[[XAP]Bob]

The chargers are standard...

There are two notable exceptions to the EU standard (Mennekes/CCS):
- Nissan use Chademo (though they now use the Mennekes, or Type2, for AC)
- Tesla have a charger designed and built before the standards really existed - but most of their UK vehicles are CCS capable anyway I believe

- Some of the Renault vehicles were AC only, but that's not contrary to the standard, it's just only implementing half of it.

All three can pretty easily be done at the same charger (as they usually are) though high speed AC does require three phase (likely provided anyway for DC charging at decent efficiency).

Mandating contactless at all chargers would be a good start.
I'm not aware of any individual dino juice discount memberships, but the price differences in EV land are all over the place. The only one that made sense to me was the Ecotricity discount, since you were using your normal electricity provider... But they don't own it any more.

A flat rate makes sense, but that's very hard to mandate.