Will Electric Cars Wreck the Grid?

[vfx]

Plug-in electric cars could destabilize the distribution of power

scientific american
Science News, Articles and Information | Scientific American

 

[TEG]

See also:
Smart Grid Data About to Swamp Utilities

And this:
California Electric-Cars Push May Raise Power Costs (Update2) - Bloomberg.com

 

[TEG]

VFX linked to the scientificamerican.com main site. Here are some more specific searches:

• Will Electric Cars Wreck the Grid?: Scientific American
• The Great Electric Car Quandary: How to Build a Charging Infrastructure Before Demand Grows
• Scientific American: Search

 

[vfx]

An "Electric Car" or vehicle search on the Scientific American site shows they are covering the scene pretty regularly.

I was looking for an article I was told about in last months issue that gives a chart on the amount of electricity it takes to make a gallon of gasoline. A favorite subject here. :smile:

 

[Norbert]

See also:
Smart Grid Data About to Swamp Utilities

Do they really have to store all the individual numbers every 15 min, for a duration of ten years? Does anyone really need to know the exact amount consumed 7 years, 3 months, 4 days, 2 hours, 45 min ago?

Does the cost per kWh really go up when more is consumed? Isn't there, in general, the effect of economies of scale such that the rates should go down? Aren't larger transformers more cost-effective than smaller ones? Or would that really require quantum physics and carbon nano tubes?

 

[DRM]

This actually isn't as big of a problem as it sounds. Although it's a lot of data, I think it might be instructive to look at how much it costs to store data commercially as opposed to how many 1000's of filing cabinets XXXMB of data fills.

For reference, jungledisk.com (one of the better online backup systems) will archive your data for 15cents per GigaByte online. According to the article, a smartmeter will generate ~400MB of data per user over 10 years. At *today's* archive prices, this is less than a dime in archive costs per customer ... or a penny a year; hardly a large portion of your electric bill.

Yes, they will need to build out storage capacity, but it's unlikely to be a critical roadblock.

//dan.

 

[dpeilow]

Electric cars must be taxed to pay for more power stations 'or National Grid could fail'

I can't say I'd ever heard of Saturn Energy before this bit of cheap publicity.


Why am I also not surprised that the Telegraph's motoring section has picked this up?

 

[EVNow]

There is plenty of unused capacity at night.

 

[dpeilow]

I recall seeing a report that said 75% of the UK's cars could go electric without impacting the grid, but I can't find it now. If anyone knows the one I mean, I'd like to send it to the Telegraph.

 

[TEG]

Could it have been a misunderstanding or mis-print. I see sites saying 75% of the grid energy can be used for travel (compared to 23% for gas). Basically the "electric cars are a lot more efficent at converting energy to motion" statement.

For example, this says:

Electric vehicles can be four times more efficient than their internal combustion counterparts. In a conventional mechanical vehicle, only 18-23 per cent of the energy contained in the fuel is converted into motion, whereas electric vehicles make use of up to 75 per cent of electricity taken from the grid.

Here was an article saying that 10% EVs could be tolerated:
UK grid capacity 'sufficient' for electric vehicles

 

[TEG]

Zerocarbonista: 'Can the grid take it?'

 

[Alfred]

Wrong consumption data - wrong conclusions

As you can calculate from the Roadster's consumption data, typically 130-180 Wh/km in normal use, a well designed electric vehicles can be around 5-10 times more efficient than a comparable gasoline powered car, particularly in urban, slow stop and go traffic. A gasoline piston engine driven car does not reach these efficiencies around 20% often quoted. That is what the engine might do on a test bed, often without energy consuming auxiliaries connected (fans, exhaust etc). A better starting point is using EPA mileages of comparably quick cars and then allow for the fact that much driving is urban, giving that a bit more weight, say 80%, depending a bit on the local scene. I did some of those calculations on my pages referenced below.

 

[dpeilow]

The Zero Carbonista link is quite interesting. I misunderstood from the title - assuming that it meant we'd need to put 12% more peak power on the grid. That is not the case:

It’s worth bearing in mind that most car charging will probably be overnight, the time of lowest grid demand, and therefore we can probably deliver this extra 12% volume without a need to increase the actual capacity of the grid. And such a large overnight load could result in a considerable smoothing of the peaks and troughs of demand on the grid and in the process make the grid more efficient cost and CO2 wise.

So looking at the previous graph, that 12% could be delivered by existing sources overnight.

In actual fact then, the grid could handle 100% of the UK fleet going electric.

 

[dpeilow]

Found this too: IET | Charge of the electric car

There is an interesting comment at the end.


I've written a letter to the Telegraph, we'll see if they publish it. Copied with added hyperlinks:

Sir,

Andy Bloxham's article on electric cars and the National Grid (Electric cars must be taxed to pay for more power stations 'or National Grid could fail') repeats a myth often put forward by EV detractors that has no basis in reality - namely that a shift to electric cars would require costly upgrades to power stations and the electricity grid. This is quite easy to disprove.

In 2007, the UK consumed just under 350 TWh of electricity (source: CIA World Factbook).

There are 31 million cars on UK roads (source: SMMT) and average mileage is 9000 miles (source: Act on CO2).

An electric car on average uses under 200 Wh per mile, thus a conservative electricity consumption figure for a hypothetical all-electric UK fleet would be 55.8 TWh per annum - or approximately one seventh of the electricity used by the country overall. Electric cars are typically charged overnight and even one charge per week could be sufficient to give average annual mileage.

During non-work hours after 5pm, electricity consumption ramps down to a level of around half that of the peak between the hours of 11pm and 6am (source: National Grid). On weekends, daytime consumption is only 75% that of weekdays. There is presently 20GW of spare capacity in the system overnight.

One can therefore easily show that there is enough underlying grid capacity for the entire population of passenger cars in the UK to become electric, with no need for any additional power stations. This conclusion is further reinforced by the addition to the calculation of capacity that would become available from the closure of oil refineries, themselves significant users of electricity during both peak and off-peak hours, which would allow daytime fast charging for the minority of people that need it.


Yours faithfully,

David Peilow

 

[AndrewBissell]

Applause!

 

[PeterW]

More Applause.

I hope they publish it.

 

[ChargeIt!]

.....

 

[vfx]

I liked it too.:biggrin:
I would only ask for a link backing the assertion "An electric car on average uses under 200 Wh per mile."

 

[dpeilow]

It's a bit of a finger in the air, to be honest. You know that on the highway it is higher, but around town less. I think the argument still holds up at 300Wh / mile, though.


I found another article while looking for something else.

Plug-in Transportation, Can the Grid Take It?

 

[vfx]

I found another article while looking for something else.

Plug-in Transportation, Can the Grid Take It?

Nice Blog site!