Tesla News & Discussion

1961Nick

GreatApe wrote: »

The UK grid was designed to work at a much higher power level than we see today
Mostly because it was designed with incandescent lighting in mind
But LEDs and more efficient appliances have greatly reduced peak loads
Peaks used to get close to 65GW now they seldom pass 50GW

As a guess a peak load of 75GW is doable with current infrastructure
By comparison the peak today is about 45GW
That's upto 30GW spare capacity during the day

That's more than enough for cars
It's also enough for at least 10 million homes on resistance heaters
Or 20 million homes on heat pumps with COP 2x
Or 30 million homes on heat pumps with COP 3x
Or 40 million homes on heat pumps with COP 4x

Regarding everyone charging at once, you are right that would be a problem
But that is resolved easily by giving different households a different cheap rate time
You might have a cheap rate from midnight to 4am
Your next door neighbor night be 00:30 to 4:30
The house in the other side of the road might be 01:00 to 5:00
And so on

So everyone doesn't start at the same time
You'd allocate these slots to inversely match other electrical demand
Such that the grid goes from whatever it is now
To roughly a steady flat demand at night
No problem at all

This isn't required now
But it would be required if there were 1+ million EVs on the road

Plus none of these things will happen overnight
It's going to take 30-60 years to electrify heating and transport
It can be done quicker, perhaps in just 20-30 years but that doesn't look likely

I completely agree that there's currently no problem generating the amount of electricity required to cope with a large EV roll out & also a gradual move to electric heating. What I have been told is that a significant amount of the local distribution infrastructure doesn't have enough headroom to cope with EV hotspots. This could be because additional properties have been added to an existing transformer/local cable ... or maybe it was just marginal to start with.

Giving households different off-peak charging windows is clearly a sensible move as long as the calculation takes account of which phase each property is on.

1961Nick

zeupater wrote: »

Hi

But that's where the need to understand the heat provision profile changes required to effectively use HPs comes in ...

HTH
Z

I doubt that there are many homeowners that could be bothered to do that. Many of them would be incapable of understanding it even if they tried to. I can see a lot of engineer call outs to 'under performing' heat pumps if they're not a comparable output to the gas boiler they're replacing.

zeupater

1961Nick wrote: »

I doubt that there are many homeowners that could be bothered to do that. Many of them would be incapable of understanding it even if they tried to. I can see a lot of engineer call outs to 'under performing' heat pumps if they're not a comparable output to the gas boiler they're replacing.

Hi

But that's not an issue that's hard to overcome ... a simple solution would be to have a control system in which the required temperature & time is set by the user & the system handles the ramp-up element to meet the provision schedule itself, same for water heating etc ... no more complexity for the consumer than they're used to, just a little different but not something that the majority of households couldn't get used to in a couple of days or so & far less complex than getting your head around energy microgeneration & home storage solutions.

Anyone specifically looking can find potential problems if they try hard enough, however, most of what they find have already been identified by others & have pretty simple solutions ... it's not as if heat-pumps are new & untried technology - if 'normal' people can manage to use them without issue throughout many other parts of the world, it doesn't say much for the education system in the UK if we're going to have serious issues & not follow the trend!

Currently drawing 260W so still well below the 4kW you'd be allocating to each and every household just for heating when sizing the grid ... as mentioned earlier, that means the entire house is currently using a similar level of power as a TV and a single lightbulb would have been using back in the 1960's, and that includes heating!!

When domestic battery costs become realistic (~£150/kW) the intention is to reduce load on the grid from this property even more & I'd guess that we'd not be the only ones doing so ... but every little helps ... :cool:

HTH
Z

1961Nick

zeupater wrote: »

Hi

But that's not an issue that's hard to overcome ... a simple solution would be to have a control system in which the required temperature & time is set by the user & the system handles the ramp-up element to meet the provision schedule itself, same for water heating etc ... no more complexity for the consumer than they're used to, just a little different but not something that the majority of households couldn't get used to in a couple of days or so & far less complex than getting your head around energy microgeneration & home storage solutions.

Anyone specifically looking can find potential problems if they try hard enough, however, most of what they find have already been identified by others & have pretty simple solutions ... it's not as if heat-pumps are new & untried technology - if 'normal' people can manage to use them without issue throughout many other parts of the world, it doesn't say much for the education system in the UK if we're going to have serious issues & not follow the trend!

Currently drawing 260W so still well below the 4kW you'd be allocating to each and every household just for heating when sizing the grid ... as mentioned earlier, that means the entire house is currently using a similar level of power as a TV and a single lightbulb would have been using back in the 1960's, and that includes heating!!

When domestic battery costs become realistic (~£150/kW) the intention is to reduce load on the grid from this property even more & I'd guess that we'd not be the only ones doing so ... but every little helps ... :cool:

HTH
Z

I pretty much have the system you have described & it's well beyond my better half's attention span. Her eyes glazed over when I tried to explain how optimisation worked & why some rooms started heating earlier than others!

Just because something is simple for you & me doesn't mean it's simple for everyone. The number of intelligent people who can't understand the basics of thermostatic control staggers me ... courtesy cars with the climate control set to max or min is a common observation.

Martyn1981

1961Nick wrote: »

No ... I'm saying it takes 5 minutes to have a shower but many hours to charge an EV. The probability of everyone in a locality having a shower at the same time is remote, but the chance of everyone charging their EV at the same time is high.


Early adoption of EVs will probably be by high mileage business users because the savings are huge compared to an ICE vehicle. These vehicles will need an overnight charge at significantly more than 680W


It might be a case of 80% of the miles are being done by 20% of the vehicles. That 20% are the ones likely to change to an EV in the very short term. There may not be as much time as you think.

Then you missed the point.

If every house has a power shower, then there's a good chance that over say 7 houses, there will be overlaps of power demand as the showers can be expected to get used at similar times in the mornings.

But if 7 houses have an EV, then based on average mileage, the average of those plugged in to charge will be around 1.

So, if your concern is power, then I've tried to give you a similar example to ease your concerns.

Also the power shower will need to operate at a certain level to provide the adequate flow and heat, whereas with simple smart charging, these could be modulated to cope with peaks, I'm sure moving forward.



Regarding the 680W, again you seem to have missed the point, you may well have one charging at 7kW, but if it's one in 7 houses, then the average per house will be 1kW.

Of course you can try to create scenarios, but, as explained, if we divide normal mileage for 30m cars, across 20m households, the average 24/7 draw would be 340W, or the average 12/7 draw would be 680W.

So if the house can cope with 7kW power, and the grid can cope with an average addition of 680W, then things look good.



Your 20% of cars doing 80% of the mileage case may be correct, or completely false, but it doesn't change the 7kW draw needed at those homes to charge, only that those homes will be charging more often, and it would actually reduce the national average additional draw I calculated by 20% (until such time as all cars become BEV's).

Also you've just shot yourself in the foot regarding peak loads within an area, as your example obviously, also concludes that 80% of the vehicles are only doing 20% of the mileage, so therefore they are only averaging ~2,000 miles pa, or 38 miles per week, so for a ~40kWh battery, they will only need to plug in approx once every 4 weeks, greatly reducing the number of cars all charging at the same time.

And those 20%, averaging about ~32k miles pa, would need to charge every other day, assuming a 50kWh+ battery.

1961Nick

Martyn1981 wrote: »

Then you missed the point.

If every house has a power shower, then there's a good chance that over say 7 houses, there will be overlaps of power demand as the showers can be expected to get used at similar times in the mornings.

But if 7 houses have an EV, then based on average mileage, the average of those plugged in to charge will be around 1.

So, if your concern is power, then I've tried to give you a similar example to ease your concerns.

Also the power shower will need to operate at a certain level to provide the adequate flow and heat, whereas with simple smart charging, these could be modulated to cope with peaks, I'm sure moving forward.



Regarding the 680W, again you seem to have missed the point, you may well have one charging at 7kW, but if it's one in 7 houses, then the average per house will be 1kW.

Of course you can try to create scenarios, but, as explained, if we divide normal mileage for 30m cars, across 20m households, the average 24/7 draw would be 340W, or the average 12/7 draw would be 680W.

So if the house can cope with 7kW power, and the grid can cope with an average addition of 680W, then things look good.



Your 20% of cars doing 80% of the mileage case may be correct, or completely false, but it doesn't change the 7kW draw needed at those homes to charge, only that those homes will be charging more often, and it would actually reduce the national average additional draw I calculated by 20% (until such time as all cars become BEV's).

Also you've just shot yourself in the foot regarding peak loads within an area, as your example obviously, also concludes that 80% of the vehicles are only doing 20% of the mileage, so therefore they are only averaging ~2,000 miles pa, or 38 miles per week, so for a ~40kWh battery, they will only need to plug in approx once every 4 weeks, greatly reducing the number of cars all charging at the same time.

And those 20%, averaging about ~32k miles pa, would need to charge every other day, assuming a 50kWh+ battery.

If you take your blinkers off for a second you might understand the point. Why do you put so much effort into distorting/rubbishing someone else's opinion?

You probably wouldn't be too pleased if your DNO fitted a 1 amp main fuse to your house because your AVERAGE use is 0.2kW/h.

Martyn1981

1961Nick wrote: »

If you take your blinkers off for a second you might understand the point. Why do you put so much effort into distorting/rubbishing someone else's opinion?

You probably wouldn't be too pleased if your DNO fitted a 1 amp main fuse to your house because your AVERAGE use is 0.2kW/h.

No need for that, I was simply addressing the issues you raised. We both agree that power showers work out OK, so just apply your reasoning on them, to BEV's.

In the case of PV, we already have inverters that can reduce or stop generation based on grid voltage, or frequency, so it seems entirely likely (as I've suggested repeatedly) that smart chargers will modulate too.

I'm not rubbishing your opinion, I'm simply trying to introduce some factual numbers to address the concerns you raise, and when we are dealing with figures on such a large scale such as:

237,000,000,000 UK miles per year from cars
30,000,000 cars
60,000,000,000kWh
20,000,000+ households

we can assume/refer to averages.

almillar

1961Nick:

It's not going to be the 'average users' that causes a problem, it's the high milers that need a lot of energy in a short period of time. These vehicles will be using 7.2 kWh chargers timed to make best use of off peak tariffs. The generators may have enough power, but will the distribution network be able to cope with EV hotspots?

Yes. And if they near capacity, they'll get upgraded. Are you determined to find a problem? Do you worry about everyone in the neighbourhood switching their ovens on at the same time?
Charging overnight is good. If they're on a cheap overnight tariff they've got, like 8 hours to charge. (8x7kw = 56kWh. At 3m/kWh that's 168 miles every single day). It will be a nice steady flow too, when there's capacity, and not peaky, so it's ideal. Using a 7kW charger doesn't get you 'a lot of energy in a short period of time' in the context of rapid chargers being 50kW and used in peak time. Great Ape agrees!! Surely we can all take comfort in that!

I have it on good authority that a significant amount of the network doesn't have enough headroom to cope with the planned EV roll out if home charging becomes the norm.

'The network' is not a static thing. It breaks, gets repaired, upgraged all the time, based on demand. And so it will continue. We indirectly pay for this via our electric bills.

Early adoption of EVs will probably be by high mileage business users because the savings are huge compared to an ICE vehicle. These vehicles will need an overnight charge at significantly more than 680W

And they'll install charger/chargers. And they'll be installed safely, and if something needs to be upgraded, it will be. They'll likely have 3 phase AC, for example.

GreatApe:
(MPG) 'Real world' is really difficult to stand over, so we should stick with the proper test figures. A load of Prius taxi drivers in London is not the real world. And hybrids, by their very nature, behave so differently on the open road vs city.

The energy otherwise wasted in breaking is saved to do some electric miles mostly the slow urban miles are replaced. Overall it's great tech if every car was hybrid you have 25-30% lower emmissions

This also applies to EVs of course, but there's a bigger battery that can be filled. EV, and the EV portion of a hybrid, are ideally suited to a city. No noise or stop/starting the engine to sit there and do nothing.

I think hybrid battery chemistry is geared to high power per kWh
Anyway you don't need huge power in hybrids because their battery and electric motor are mostly used for the slow 0-30 which doesn't need a huge amount of power

I think you need to look at how you get 'high power per kWh' out of a Li-Ion cell (or even NiMh for many Toytotas), and again, how that would differ from a full EV. PHEV makers have cars on the road, right now, that happily do 60MPH on EV only. Just seems like a real backward step.

Think of hybrid tech as improving fuel economy from circa 45mpg to 65mpg
Or more accurately almost no improvement on the motorway
But going from ~30 to over 60 in urban driving

Yes, that IS how I think of hybrid tech. Good for short urban journeys, not translatable to big motorway ones. That's why I think it's so dangerous to quote one single MPG figure, 'real world' or not.

Sure if you're going to sell 40 cars it's better to sell 40 hybrids rather than 1 leaf and 39 ICE

Why not 40 Leafs?! Your answer is cost vs ICE of course, but our whole argument is that the price gulf is not as big as you claim.

For those that say hybrids have two lots of costs
Not quite Because you can go from a 160HP petrol engine to a
80HP electric + 50HP petrol setup so the petrol side can be smaller/cheaper/lighter than a pure ICE
And the electric side is significantly lighter as you only use 10KWh of batteries rather than 50KWh

You cannot. When the EV runs out people will slow down on the motorway with their 50hp petrol engine. Unacceptable safety risk. I've told you about the BMW i3 ReX before (EV with petrol generator, generator charges the battery, is not attached to the wheels). Close to what you're talking about, numbers are different, and so few people bought them in the UK that BMW aren't selling it in the UK any more.

Which we know so far BEVs haven't gotten cheaper
Tesla model 3 released 2.5 years ago....is it cheaper today? No

How many times should I mention Zoe doubling in capacity in 6 years remaining the same price? Model 3 can't keep up with demand so Tesla aren't inclined to discount it. Blantant lie. We can make zany predictions all we like, but you're saying here EVs HAVE NOT got cheaper. They HAVE.

Such unmetered (at the socket) electricity infrastructure would be so easy so cheap to deploy

Agreed. Literally in lampposts. Would be great and help solve the often used 'I can't install a chargepoint at home' problem.

Average price of the top 10 selling cars in the UK £16,000
Model 3 £40,000

Model 3 is a car I would describe as 'above average'.

pile-o-stone

1961Nick wrote: »

I think your house is about as far from typical as it's possible to get in terms of energy requirements! My boiler will run at around 16kW for at least an hour before it settles down to maintaining rather than increasing the temperature. With a COP of 4 (on a very cold day) that's still 4kW for heating plus another couple for DHW.

Isn't it the case that the government intends on banning new homes from having gas boilers, rather than forcing existing homes to fit HPs?

If that's the case, then new homes have a level of insulation and airtightness that's even Z's advanced home, so the power consumption would be similar if not better than Z's.

Plus they they will have underfloor heating or oversized radiators that are designed to run at lower hot water temperatures than conventional radiators.

I really don't see older properties converting across from gas boilers to heat pumps without a major incentive scheme from the government to insulate older homes, improve the airtightness and fit oversized rads.

zeupater

1961Nick wrote: »

I pretty much have the system you have described & it's well beyond my better half's attention span. Her eyes glazed over when I tried to explain how optimisation worked & why some rooms started heating earlier than others!

Just because something is simple for you & me doesn't mean it's simple for everyone. The number of intelligent people who can't understand the basics of thermostatic control staggers me ... courtesy cars with the climate control set to max or min is a common observation.

Hi

If that's based on a multi-zoned electronic TRV system then in complexity terms that's far beyond what was described or is needed ... everything would either be set within the heat-pump itself or within a remote panel ... there's really not much difference in complexity between setting a start time for the heat to come on at a particular temperature and a time that a required temperature should be attained, furthermore, there's absolutely no real need for any change at all if all those classified as 'intelligent people' (or even those blessed with less intelligence!) need to understand is that simply setting the heating timer to come on a little earlier would negate the need to oversize the HP and therefore potentially save them £thousands both up-front & every time the system needs replacing ...

The problems you're looking for & worrying about simply don't exist in the 'real world' in the form that you're describing ... just look at Germany where around 20%-25% of new homes are being built with heat-pumps, a considerable proportion of which are represented by large clusters of homes in concentrated developments ... surely this mirrors what you're worried about, but the grid seems to cope in that situation there, so why would it be considered any different here - in most situations all that would likely be needed if there was to be an issue would be an uprated transformer in the locality.

National Grid are aware of what's happening on both electrification and distributed generation and their regularly published reports don't seem to convey panic, quite the opposite really ... if they're pretty happy I can't see where the negativity comes from - after all, if they've got it wrong you'll still have your gas boiler & backup battery for a few years yet and there's always the option of fast-charging the car elsewhere! ... :D

HTH
Z