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Topic Title: Electric Car Motorists could strain the power supply
Topic Summary: say sources........
Created On: 14 July 2017 08:04 AM
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 14 July 2017 08:04 AM
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Zoomup

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Joined: 20 February 2014

If we charge up our electric cars at peak times it is suggested that we could put a large strain on the distribution network says National Grid in a recent Times article. Britain has about 100,000 electric cars on the road at present but that figure is projected to rise to millions by the early 2020s.

National grid said that if left unmanaged this situation has the potential to challenge the system networks and system operators post 2030.

By 2030, uncontrolled charging could add up to eight gigawatts to peak power demand. This is close to the maximum power output of Britain's entire nuclear power stations. The demand could be reduced to 35 gigawatts if drivers use "smart charging" where their cars automatically wait to draw power from the grid when supplies are plentiful.

Another link on the same subjecthttp://www.renewableenergyworl...wer-supply.html


Z.
 14 July 2017 09:25 AM
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di515223

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This is one of the drawbacks of electric propulsion - Drivers will want the convenience they have now of being able to replenish fuel whenever they want.
I suspect the next generation of chargers will have local storage to store the enery off peak, for loading as required.
This will cause a great amount of change, but, in my opinion, is the oly way this will be manageable.
there is always a downside to any system, and electricity has the drawback of being expensive to store in relatively small quantities.
If there was standardisation of systems, that would be a help, but physics limits the speed of loading the energy - 50L of diesel can be pumped into a car in less than 3 minutes, but so far there is no practicable charging system that can transfer the same amount of energy in the same time - 50L of fuel contains roughly 0.5 MWh, so high speed charging would need either very high voltages or currents so high the connector would be to heavy to lift!
I don't see any simple solutions other than charging in an off-peak environment -either direct to the car, or to some other storage system (still to be commercially viable)

Dave
 14 July 2017 11:04 AM
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rogerbryant

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There has been quite a lot of comment recently regarding the problems of charging electric cars. One German Green minister went somewhat against the party whip in his comments.

http://notrickszone.com/2017/0...h.z1gUv38j.dpbs


In the ensuring discussions I posted this on another forum:

----------------------------------------------------------------------------------

There is a lot written regarding the replacement of fossil fuelled (petrol and diesel) cars with electric cars. Some suggest it is easy, others suggest it is impossible. I decided to look briefly at the electricity requirements required to do this in Germany.

First step how much petrol and diesel is currently used?

From the IEA
http://www.iea.org/publication.../GermanyOSS.pdf


Germany petrol and diesel consumption 2010-2011.
Petrol 450 000 barrels per day
Diesel 1050 000 barrels per day

As a cross check on the total consumption:
http://world.bymap.org/OilConsumption.html

Total consumption petroleum consumption for Germany 2015
2 372 000 barrels per day

Next step what is the electrical energy equivalent of 1 barrel of Petrol/Diesel? From a couple of sources:

http://peakoil.com/generalidea...a-barrel-of-oil

1 barrel (crude) is 1,700 kilowatt hours

http://letthesunwork.com/energ...relofenergy.htm

A barrel of oil contains about six gigajoules of energy. That's six billion joules or 1667 kilowatt-hours

If we take 1.7 MWh per barrel for petrol annual automotive energy input is:

Petrol 765 000 MWh per day= 765 GWh per day = 279 000 GWh = 279 TWh

Assuming an efficiency of 20% for a petrol vehicle the energy required for petrol automotive use in Germany is 55.8 TWh per year.

Taking an overall efficiency for an electric vehicle to be 80% (electricity transmission losses, battery charging efficiency) replacing the petrol vehicles with electric vehicles would require 70 TWh per year.

What proportion of the diesel is for automotive use against road or rail transport is not obvious. Suggesting a total of 100TWh for the annual automotive consumption seems reasonable.
If all the diesel consumers were replaced by electric vehicles the annual electricity consumption would increase by around 220 TWh per year.

Currently Germany produces around 600 TWh of electricity annually.
https://www.cleanenergywire.org/factsheets/germanys-energy-consumption-and-power-mix-charts

Increasing this to 700 TWH to allow for the charging of electric cars is not trivial, nor is the reinforcement of the distribution infrastructure. Increasing to 820 TWh to replace all fossil fuelled transport is probably impossible in the suggested time scales.

------------------------------------------------------------------------------------------

I would expect the numbers to be similar for other large European countries and will require very significant infrastructure investment.

As ever please feel free the challenge the assumptions and check the arithmetic (It is not unknown for me to drop a 0 somewhere)

Best regards

Roger
 14 July 2017 11:41 AM
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broadgage

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IMHO, what is needed is a simple to understand charging control that takes account of the differing price of electricity at different times

For example

"press the red button to charge as quickly as possible, regardless of cost.
Press the yellow button to charge at a lower price, subject to the delay not exceeding two hours
press the green button to charge at the lowest possible price, subject to the battery being at least 85% charged by 07-00 next morning"

That would give the consumer the option of fast charging during the evening peak, if they expect to need the vehicle later in the evening.
This would be relatively expensive.
The other options would be appreciably cheaper.
Cost per charge might be in the region of £10, £4 and £2 for the three options, depending on battery size.
 14 July 2017 01:46 PM
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AJJewsbury

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, but so far there is no practicable charging system that can transfer the same amount of energy in the same time

presuming of course that the batteries are hard-wired into the vehicle. If however the batteries were exchangeable (like any child's toy or battery drill) then it need take only as long as sliding out one rack and sliding in another - maybe less than 30s if you were organised about it. Batteries would then be treated rather like gas bottles - consumer pays just for the contents and a bit towards their eventual replacement and their long term maintenance & checking is done by an organised company rather than left to individuals.

- Andy.
 15 July 2017 11:49 PM
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ectophile

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Originally posted by: AJJewsbury

, but so far there is no practicable charging system that can transfer the same amount of energy in the same time


presuming of course that the batteries are hard-wired into the vehicle. If however the batteries were exchangeable (like any child's toy or battery drill) then it need take only as long as sliding out one rack and sliding in another - maybe less than 30s if you were organised about it. Batteries would then be treated rather like gas bottles - consumer pays just for the contents and a bit towards their eventual replacement and their long term maintenance & checking is done by an organised company rather than left to individuals.



- Andy.


The trouble is that the battery packs are designed around the car, and vice versa. Even where they are swappable, such as on some Teslas, you would have to have the correct battery on hand for the specific make and model of car. To make it worse, the battery technology improves over time, so whoever offers the battery swaps may end up lumbered with a load of obsolete battery packs.

-------------------------
S P Barker BSc PhD IEng MIET
 16 July 2017 01:31 AM
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potential

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I don't know about you but if I bought a new car with a new battery (costing £1000s) I would not want to swap that battery for one that was well-used and probably well down its capacity and life expectancy curve.

I know how I've felt in the past when exchanging gas bottles.
Mine a bright shiny new one but empty and the replacement full but looking as though it has seen better days.
Of course that is just cosmetic but with batteries the storage capacity will be just as affected too.
 17 July 2017 07:31 AM
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di515223

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The other issue with battery swapping is the need to move very heavy and awkward patteries into a tight space, and then handle high energy connections. The battery for a small town runaround is unlikely to be compatible with a full size family car.
Battery swapping can be done, but it needs a lot of standardisation, and investment in a large stock of exchange batteries, neither of which are likely to be attractive to the industry.
Maybe we need to look at how the charge is transmitted to the car, and start scoping the alternatives, such as inductive coupling to buried coils in car parkin areas etc. This would of course require in - car metering to be totally automatic and fair. There are many alternatives, but they must be usable to the non technical end user, who sometimes has difficulty when faced with an unfamiliar fuel pump at present!

Dave
 17 July 2017 12:01 PM
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davezawadi

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In my view the price of an electric vehicle should include the infrastructure to provide its power, and it should be limited to charge only when the grid has significant green spare capacity. So at night on a hot evening with no wind its "sorry squire"! Just moving the fuel burning to a power station from the car is of very dubious value to anyone, and is very expensive. Otherwise the "greening of transport" has very little meaning, just PC value, which I despise.

-------------------------
David
BSc CEng MIET
david@ZawadiSoundAndLighting.co.uk
 17 July 2017 12:17 PM
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OMS

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I think we need to be a bit more holistic, Dave - take a longer view of things

Rather than limit EV to only the power generated from "green sources" and stifling demand we should be maintaining focus on "greening the grid" over time and encouraging EV take up

Yes, the first few generations of EV will shift the dirty fuel burning from car to power station (although burning gas centrally is probably greener than burning Diesel locally) - as we green the grid, the effect becomes magnified due to the next generation of EV's coming through with much more users of them

Intelligent design would be looking at EV's as a sensible storage source for green generation - basically bi-directional energy flows. Relatively easy to do once we have a lot more EV's on the roads (and parked up outside houses, shops, offices etc

We have EV charging points at our office (two for "visitors" and two for our EV "pool cars") - it's surprising when you look at the charging patterns - most of the EV is actually supplied from PV with relatively small "grid input" during the worst months - the grid just acts as a storage mechanism actually

Regards

OMS

-------------------------
Let the wind blow you, across a big floor.
 17 July 2017 01:22 PM
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ectophile

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Originally posted by: davezawadi

In my view the price of an electric vehicle should include the infrastructure to provide its power, and it should be limited to charge only when the grid has significant green spare capacity. So at night on a hot evening with no wind its "sorry squire"! Just moving the fuel burning to a power station from the car is of very dubious value to anyone, and is very expensive. Otherwise the "greening of transport" has very little meaning, just PC value, which I despise.


It usually does, in the form of a charging socket.

The rest of it you're already paying for in the form of the standing charge and the pence per unit for the electricity that you're using to charge the car.

If the suppliers can't get their act together and actually supply the customers who are paying them, then that's their job to fix.

-------------------------
S P Barker BSc PhD IEng MIET
 17 July 2017 02:48 PM
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davezawadi

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I cannot agree that the electricity price already includes 25-50% increase in generating capacity, in fact capacity is already far too small and we get very close to failure on occasion. Whilst I have some sympathy with OMS's comments, using your very expensive battery with limited cycle life (and also the likelihood it won't be charged when you want to use the car) this is a sop to those who think all this is a "good idea". I read a suggestion yesterday that someone recons to build a huge battery storage facility for England, which must be one of the most curious proposals ever. First the required capacity to run GB for a few days when there is no wind is something like 2TWh. Even if you did build such a battery, it would be immensely dangerous unless dispersed over a very wide area, the energy being something like 100-1000 H bombs! Battery life is a very significant problem whatever one does, and at present is about 3 years of continuous daily use. Then there is cost, presently about £10 -50 per kWh.
Significant storage needs all of upland Wales to be surrounded with a huge dam to build a pond and a big increase in pumped storage, but I don't see this being very popular with OMS! Lithium batteries are probably not the answer, although OK for laptops and phones, what is needed is a battery technology with many times the storage capacity, very low cost and no limit on lifetime. All of this is probably impossible as Lithium is already the most chemically active metal and the only more active element is hydrogen. OK you say use hydrogen fuel cells, but these are expensive and need very pure hydrogen to last, the only source of that being electrolysis from electricity, and the overall efficiency is not great. LPG has not proved popular for cars despite the low cost, as fuel capacity is small and only sold in a few places.
Fossil fuels are very difficult to replace, and stopping use for transport would not make a lot of difference to anything, and we have overcome most of the pollution problems with technology. The "Diesel" problem is due to one problem and that is simple, we have suitable catalysts to remove NOx already fitted, but these don't work at idling temperatures, but no one is prepared to fix the traffic jams which waste much time and keep the catalyst inoperative!
As usual the whole subject needs to be considered at once, not piecemeal as is usual with politics. It appears to me that engineering has failed to engage with everyone else, partly because they don't want solutions, just someone else to complain about.
I'm always happy to discuss these things face to face but not in print, those who disagree are very happy to engage in violence and suppression because it doesn't match their agenda, both of which are the response of extreme politics.

-------------------------
David
BSc CEng MIET
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 17 July 2017 03:23 PM
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mapj1

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The other side of this is how many journeys are really needed at all. It may be that the proper fix involves living and working with less separation. I find it remarkable that when you make transport cheap, or at least you subsidise it with Londion weighting allowances to Salary to buy train tickets, then as this animation shows
3.1 million London folk commute in and out of London daily

And yet this like moving 1/2 to 2/3 of the total population of Scotland across the M25 every morning and back again every evening, which if proposed, would be rightly shouted down as madness.

To do what ?- no magical crops are grown inside the M25, and no great parts are manufactured that could not be made elsewhere , so why ? Perhaps could not much of it be done by the same people but not travelling quite so far. Does processing an insurance claim need the person reading it to be on the 12th floor, for that matter, does anywhere need to be so densly overused and overloaded we need a 12th floor at all really?

Because it is too cheap to do so.

-------------------------
regards Mike


Edited: 17 July 2017 at 11:55 PM by mapj1
 17 July 2017 03:39 PM
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davezawadi

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Possibly London public transport is too cheap, but they do have an enormous advantage. Nowhere else in the country do you have trains every few moments to anything like the area of London. Once you are outside the M25 there are few trains and they are quite expensive. The M25 is the only viable route from one side of London to the other for goods, and as soon as you are off the tube network for anyone going further then a few miles from central London. Driving in central London with a lorry is no fun at all, it is very slow, there are cyclists and pedestrians everywhere running in front of moving vehicles, there are one way systems, jams, endless restrictions and bus lanes which are empty but carry a huge fine! Unloading is terrible to impossible. Many people are forced to commute large distances to work in London, from places without reliable rail connections. How else can they get to work? Remote working is only a slight answer, despite the internet. We are social beings and being alone at home is not necessarily pleasant. Many people find it difficult to work well, and it destroys leasure time at home because it feels like work. No simple answers.

-------------------------
David
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 17 July 2017 04:37 PM
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OMS

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Significant storage needs all of upland Wales to be surrounded with a huge dam to build a pond and a big increase in pumped storage, but I don't see this being very popular with OMS!


I'm fine with it actually, Dave - it's all about using the resources

There are plenty of upland areas right across the UK that can all play a part in pumped hydro for storage - and for generation actually

Severn and Humber barrages, also - bring it on - Swansea Bay Lagoon - lets have more of them and that would eliminate a lot of grid battery schemes at the moment as we don't so much need them for storage, more so for stability as the march of PV continues apace

Basically, I'm happy with a few big hydro schemes to complement the new and existing nuclear as they are big rotating units

Back in the day, I did a study on combining water distribution with generation looking at multiple low head turbines running right down the Elan valley - need to flood a few more hectares, but a perfectly feasible scheme to combine generation with storage and incorporating wind and solar into the mix

Add to that gasification of crop waste into methane and line pack the gas grid and we are nearly there

Pity we didn't put all the cash from Quantative Easing into Infrastructure - we'd be in far better shape now

I agree with Mike on this - get the demand down basically. I travel from one end of the country to the other every week in a diesel car - for no other reason that the client wants his consultant close to him

I would happily do a few miles in an electric car and work closer to home, use Skype etc etc - but UK PLC is a bit backward in this respect

Regards

OMS

-------------------------
Let the wind blow you, across a big floor.
 17 July 2017 05:30 PM
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Zoomup

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 17 July 2017 08:04 PM
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alancapon

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A shame to have a newspaper's interpretation when the National Grid report is freely available here.

Regards,

Alan.
 18 July 2017 09:39 AM
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Zoomup

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Commuting is still popular apparently. HS2 is still progressing nicely we are told. http://www.dailymail.co.uk/new...homes-demolished.html

Z.
 18 July 2017 09:47 AM
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Zoomup

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Originally posted by: alancapon

A shame to have a newspaper's interpretation when the National Grid report is freely available here.



Regards,



Alan.




"In summary
In a world where almost all cars will be electric:
? 43% of car owners will not have access to
off street parking
? too many domestic charging points will
cause network stress."

OOOOooohh Eeerrrr!


Z.
 18 July 2017 01:27 PM
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ectophile

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There is a scheme to convert existing lamp posts into charging points http://www.thisismoney.co.uk/m...posts-EV-chargers.html. This is a lot cheaper than installing thousands of separate charging points.

But is does seem to rest on the assumption that with street lamps being converted to energy-efficient LEDs, then there's now enough capacity in the wiring to handle several cars charging at once.

-------------------------
S P Barker BSc PhD IEng MIET
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