Looks like the party is over....

[JamesPa]

39 minutes ago, Beelbeebub said:

A bit off topic but I don't think people have range anxiety. 

 

They have refueling anxiety.

That's very perceptive! Also spot on and a better description.

[Michael_S]

2 hours ago, MrPotts said:

I think a scop of 4+ is needed to breakeven the cost of gas v's electricity.

Depends a bit how efficient you think a gas boiler is in terms of KWH of gas per kwh of heat.

[Michael_S]

2 hours ago, MrPotts said:

I think a scop of 4+ is needed to breakeven the cost of gas v's electricity.

Depends a bit how efficient you think a gas boiler is in terms of KWH of gas per kwh of heat.

[SteamyTea]

3 hours ago, sharpener said:

And as you say a petrol fill-up only takes 5 mins.

I filled up today, well put 30 litres in.

The car in front of me was already filling up, was ten minutes before they came back to the car (with coffees), then 4 minutes before they pulled away.

I filled up in 3 minutes (pay at pump).

So a total of 17 minutes.

Now a 150 kW charger could probably pump in 40 kWh in that time, so about 160 miles.

 

3 hours ago, MikeSharp01 said:

the elephant in the room problem is that we don't have enough electricity to move

I looked at this a few years back, worked out that we could charge 3.5 million cars without any changes (apart from charging points), and 7.5 million cars with minor changes, but all without adding capacity or infrastructure.

I posted it up here somewhere.

[MikeSharp01]

7 minutes ago, SteamyTea said:

3.5 million cars without any changes (apart from charging points), and 7.5 million cars with minor changes

Yes but there are 35 million cars registered in the UK!

[SteamyTea]

10 minutes ago, MikeSharp01 said:

Yes but there are 35 million cars registered in the UK!

We are not going to wake up tomorrow with nothing but EVs in all our drives.

2021 there were about 190k, 2022 270k, 2023 315k, 2024 382k and 2025 (TD) 386k.

So still going to take a while.

[SteamyTea]

6 minutes ago, SteamyTea said:

We are not going to wake up tomorrow with nothing but EVs in all our drives.

2021 there were about 190k, 2022 270k, 2023 315k, 2024 382k and 2025 (TD) 386k.

So still going to take a while.

(the numbers are new registrations, there are about 1.7m BEVs)

 

Edited 23 hours ago by SteamyTea

[marshian]

16 hours ago, HughF said:

Even if we do, it’s far more efficient to burn it in a CCGT, transmit the energy to the home as electricity, then run a heat pump with that electricity than it is to pipe the gas and then burn it in the home.

 

Breakeven point for efficiency is a scop of 2.8 iirc.

 

Is that considering the utterly dreadful efficiency of 50-60% of a CCGT - I get your point about transmission issues (and losses) for gas supply but I'm running a gas boiler at 97.5% efficiency on CH and 89% on HW

 

What about the electricity transmission losses?

[Crofter]

If fiddling with the cost of electricity/gas is part of this, the progressive approach would be to reduce standing charges, which have become inflated in recent years.

[Andehh]

15 hours ago, MrPotts said:

I think a scop of 4+ is needed to breakeven the cost of gas v's electricity.

We run a COP of about 3 atm (heavy users of hot water), but with off peak leccy at 7.5p being 90% of our ASHP energy usage, we're making significant savings vs gas. We also then run the dish washer etc during that off peak rate.

 

Then we don't pay a gas standing charge which is the icing on the cake. 

 

With this setup, even a COP of 2, we would work out cheaper then gas I recon. 

[Beelbeebub]

13 hours ago, sharpener said:

 

Yes, my first 4-wheeled vehicle was a s/h Viva van, the tank only held 7 gals which was good for just 200 miles.

 

Which going to the Fringe meant one stop between London and Edinburgh and I knew where all the Jet stations were. 

 

And as you say a petrol fill-up only takes 5 mins.

 

ln contrast the EV takes at least 10 for a useful addition to the range and the best part of an hour from empty to full. I have had my fair share of charging points being ICEd in, and having to detour via 3 charging stations late at night before I found one that would accept normal c/cards. That's certainly anxiety-inducing. So it's very handy to be able to get from Cambridge to Romsey and back on one charge.

This illustrates my point very well. 

 

You need the range to go there and back on one charge because you're anxious about the trouble of trying to charge away from home. 

 

Which isn't a.worry with ice cars.

 

Imagine if petrol stations were really rare and had very slow pumps, 30mins to fill

 

Your 200mile can would be pretty stressful. Everyone would want huge tanks, which would take even longer to fill etc. 

 

Some of the new generation of Chinese LFP batteries can charge at 10C, ie they can fill in 6 minutes (assuming you have a powerful enough charger). In practice it's a hit linger because of charge curves but people don't usually fill 0-100, it's 20-90 or something. 

 

For a 100kwh battery that's a 1MW charger! 

 

But for a 30 kwh battery ,which could do 120 miles, you only need 300kw, which are not impractical.

 

My longest daily trip is London and back 150mi each way. I do it a few times a year. 

 

Currently easy on one tank. 

 

If I had an electric 150m range would be doable *if* I could guarentee an easy fill up at the other end. Otherwise I need 300 miles (plus reserve) 

[Beelbeebub]

8 hours ago, marshian said:

 

Is that considering the utterly dreadful efficiency of 50-60% of a CCGT - I get your point about transmission issues (and losses) for gas supply but I'm running a gas boiler at 97.5% efficiency on CH and 89% on HW

 

What about the electricity transmission losses?

The 250% figure is for kwh delivered at your house (including transmission losses) assuming a 100% efficency boiler. 

 

Ie volume of gas burned in a ccgt plant is 2.5x the volume of gas burned in a gas boiler to deliver 1kwh of heat in your living room. 

 

So, as long as your heatpump can achive a Cop of 2.5 or better you will burn less gas in the power plant than you would in your boiler. 

 

2.5 is pretty achievable in all but the most ham fisted installation. 

 

If we snapped our fingers and swapped every domestic gas heating system with a heatpump and created enough ccgt plants to power them, our national gas demand would fall. 

 

[JamesPa]

8 hours ago, marshian said:

 

Is that considering the utterly dreadful efficiency of 50-60% of a CCGT - I get your point about transmission issues (and losses) for gas supply but I'm running a gas boiler at 97.5% efficiency on CH and 89% on HW

 

What about the electricity transmission losses?

Transmission losses and power station efficiency etc are all accounted for on the published figures for carbon intensity of fuels, which are updated annually.

 

The carbon footprint from UK domestic electricity per kWh is about 10% less than that of domestic gas, furthermore it's falling as we move to renewables.  That means that a heat pump with a cop of 3 causes less than one third the carbon emissions (actually it's a bit better still than that because most has boilers are set up by the heating industry in a way that makes them less than 100% efficient).  

 

This stuff is well established and the carbon case for heat pumps irrefutable.

[sharpener]

2 hours ago, Beelbeebub said:

You need the range to go there and back on one charge because you're anxious about the trouble of trying to charge away from home. 

 

Yes. And although we need to stop for a PNB and to eat our sandwiches we have a couple of quiet favourite spots for this and not at e.g. the Fleet Services on the M3. 

 

And the cost, I can charge at domestic off-peak rates at home even if it takes 4 nights on a 16A outlet.

[Mr Punter]

I have just had gas combi boilers fitted in 3 small new build flats.  Much cheaper to do, customers know where they are regarding costs, very little space used, no outside units.  I appreciate that ASHPs have their advantages, but they are not always the best solution.

[ProDave]

I am not sad to see the end of this silly scheme, because it has failed to deliver low prices to the consumer and instead just let the contractors trouser most of the grant and still charge the customer a lot to fit a heat pump.

[Oz07]

35 minutes ago, Mr Punter said:

I have just had gas combi boilers fitted in 3 small new build flats.  Much cheaper to do, customers know where they are regarding costs, very little space used, no outside units.  I appreciate that ASHPs have their advantages, but they are not always the best solution.

Expect to be dismissed. Not many will view it from any other perspective. 

[ProDave]

I am often asked should I swap from a gas boiler to an ASHP.  I ask what are your expectations and reasons for doing so?

 

If they just want to save money my usual reply is don't bother.

[JamesPa]

3 hours ago, ProDave said:

I am often asked should I swap from a gas boiler to an ASHP.  I ask what are your expectations and reasons for doing so?

 

If they just want to save money my usual reply is don't bother.

As a recent ASHP owner I would probably agree (although I do save a significant amount of money with mine)

 

However I would also say that, if you want a much better heating experience with a house the whole of which is comfortable 24*7 for about the same or possibly less running cost then do bother.  (Obviously also if you want to reduce the carbon footprint  of your heating by a factor of 3 they do bother)

 

Low temperature heating (the conversion to which makes up a major part of the differential cost) is just so much better, but how many people who haven't experienced it know that?.  Just be sure to do your research so you avoid the cowboys, as you must for absolutely anything which involves any of the building trades which, lets face it, are in parts about as dodgy as it gets. 

Edited 4 hours ago by JamesPa

[ProDave]

2 minutes ago, JamesPa said:

However I would say that, if you want a better heating experience then, do bother.  Low temperature heating (the conversion to which makes up the major part of the differential cost) is just so much better.  If you want a house, the whole of which is much more comfortable 24x7 for about the same cost or a bit less, then do bother.  Just be sure (like absolutely anything which involves any of the building trades) to do you research so you avoid the cowboys. 

Most of that is not the ASHP but how the system is put together.

 

I am just back from a week with a relative with a gas boiler and radiators.  It has to be the worst set up install I have seen. (or perhaps I am just used to low temp UFH?)

 

Her heating comes on for an hour in the morning, and hour at lunch time and a couple of hours in the evening.  When it is on, the radiators run far too hot to touch, to the point you could easily burn yourself I think.  You feel the hot air rising from them almost like a fan heater.  So if you are close to the radiator you feel too hot, the other side of the room, not so.

 

It is never on long enough to properly heat the fabric of the house, so when it goes off the house cools down quite quickly.  The occupant just puts a cardigan on when it gets cold in the off periods.

 

She only has it on for short periods because she is worried about cost.

 

If the temperature was turned down a LOT the radiators would be warm, not scalding hot, and left on longer the house would probably be more comfortable for no extra cost.

 

But so many people accept this scalding, too hot then too cold cycle as "normal" and never question it.

 

[JamesPa]

14 minutes ago, ProDave said:

Most of that is not the ASHP but how the system is put together.

I know that and acknowledge it in my post - I quote: 'Low temperature heating (the conversion to which makes up a major part of the differential cost) is just so much better, but how many people who haven't experienced it know that?.'

 

However the cost comparison that you do is with your typical 'shove in a 28kW boiler, whack the flow temp up to 75, ignoring the fact that it wont condense, and let it cycle like mad on the TRVs and Thermostats, with the consequent temperature gradients across rooms and temperature swings with time' crap that our heating industry has been installing, its not the well put together low temperature system you speak of above.  The latter needs the same care, and mostly the same components, as an ASHP system.

 

So yes if you want a crap heating system that costs more to run than it should go for the cheapest to install, which is undoubtedly to shove in a 28kW boiler, whack it up to 75C, and let the TRVs 'sort it out'.  If you want a system that keeps you comfortable then go for something much better, which will cost about the same to install whether the heat source is ASHP or gas and, if you get it right, will be a bit cheaper to run in the latter case (a lot cheaper if you have batteries and/or solar PV) and much greener.

 

Obviously there are many that can only afford the capital for the first of these, but equally there are many who would happily pay for better if (a) they knew the option existed and (b) our heating industry were capable of delivering it at scale, which at present I doubt it is.

 

 

 

Edited 4 hours ago by JamesPa

[JohnMo]

11 minutes ago, ProDave said:

If the temperature was turned down a LOT the radiators would be warm

And not be hot enough to heat the cylinder (assume not combi). 

 

But most people just believe if you only have heating on for short bursts it save money. Forgetting they have a boiler capable of 30+kW and it runs flat out for those short bursts. So 4hrs flat out, instead of 18 to 24 hrs ticking away.

[JamesPa]

9 minutes ago, JohnMo said:

And not be hot enough to heat the cylinder (assume not combi). 

 

But most people just believe if you only have heating on for short bursts it save money. Forgetting they have a boiler capable of 30+kW and it runs flat out for those short bursts. So 4hrs flat out, instead of 18 to 24 hrs ticking away.

... and the heating industry is content not to inform them, because it is so easy to whack in a 28kW boiler without thinking and let the controls 'sort it out'.  This is of course at considerable cost to the customer both in comfort and expense, and with the added benefit to the industry that they get to sell lots of unnecessary controls!

 

We are stunningly backward in the UK.  Some continental european countries mandated weather compensation decades ago.  I presume our heating industry lobbied against and unfortunately our Government wouldn't have had the technical knowledge to overrule them.

 

I confess that, despite having a degree in physics, I was ignorant of this myself until I started researching heat pumps (and thus heating systems in general) about 3 years ago.  Its only slowly dawned on me how misled we have been by the industry in this country and how backward it is.  For the avoidance of doubt Im not saying we are unique, but we could be a lot better.

Edited 4 hours ago by JamesPa

[JohnMo]

6 minutes ago, JamesPa said:

... and the heating industry is content not to inform them, because it is so easy to whack in a 28kW boiler without thinking and let the controls 'sort it out'.  This is of course at considerable cost to the customer both in comfort and expense, and with the added benefit to the industry that they get to sell lots of unnecessary controls!

 

We are stunningly backward in the UK.  Some continental european countries mandated weather compensation decades ago.  I presume our heating industry lobbied against and unfortunately our Government wouldn't have had the technical knowledge to overrule them.

 

I confess that, despite having a degree in physics, I was ignorant of this myself until I started researching heat pumps (and thus heating systems in general) about 3 years ago.  Its only slowly dawned on me how misled we have been by the industry in this country and how backward it is.  For the avoidance of doubt Im not saying we are unique, but we could be a lot better.

It's all indicative of cheap energy, we had many decades of cheap energy - no one cared, the consumer accepted what they were given because that was the norm and NO ONE knew any different. The professionals should have, but they had inadequate training - trouble is most aren't knowledgeable now in low temperature systems. Training is poor, everyone is an engineer (unfortunately there aren't many Engineers).

[Mike]

8 hours ago, Beelbeebub said:

If I had an electric 150m range would be doable *if* I could guarentee an easy fill up at the other end. Otherwise I need 300 miles (plus reserve) 

Or get a car where you can swap the batteries about as quickly as filling one with fuel, when they reach the UK: https://www.youtube.com/watch?v=WOsy_EvtHr4