Research determines integration of plug-in electric vehicles should play a big role in future electric system planning

Research determines integration of plug-in electric vehicles...
NREL engineer Matteo Muratori, author of the new Nature Energy paper "Impact of Uncoordinated Plug-in Electric Vehicle Charging on Residential Power Demand," said his research points to key areas where additional investigation is warranted. Credit: Dennis Schroeder/NREL

An influx of plug-in electric vehicles (PEVs) charging without coordination could prove challenging to the nation's electric grid, according to research conducted by the U.S. Department of Energy's National Renewable Energy Laboratory (NREL).

Matteo Muratori, a transportation and energy systems engineer at NREL and author of the new Nature Energy paper, "Impact of Uncoordinated Plug-in Electric Vehicle Charging on Residential Power Demand," created a computer simulation to explore the effects of in-home charging on the .

"Realizing the full benefits of vehicle electrification will necessitate a systems-level approach that treats vehicles, buildings, and the grid as an integrated network," said Johney Green Jr., NREL's associate lab director for Mechanical and Thermal Engineering Sciences.

"Previous research into the amount of energy required by homes hasn't taken into account plug-in electric vehicles," said Muratori, who holds a Ph.D. in mechanical engineering. "Given that more people are choosing to drive these types of vehicles and charging them at home, this additional demand should not be overlooked."

The simulation concluded that a PEV market share of up to 3 percent, which translates to about 7.5 million vehicles, does not significantly impact the aggregate residential power demand. More than 600,000 were already on the road at the end of 2016, a figure that includes about 150,000 sold during the year.

Muratori also looked at the impact PEV charging might have on a residential distribution transformer. In this case, a problem arises when motorists gathered in a geographic area began buying these vehicles and plugging them in to recharge upon returning home—a practice known as uncoordinated charging. Even without large numbers of PEVs on the road, this clustering effect "will significantly increase the peak demand seen by distribution transformers and might require upgrades to the electricity distribution infrastructure," according to Muratori's paper.

The research also looked at whether the household used the less-powerful Level 1 charging option or the more-powerful—and therefore faster—Level 2 charging option. Muratori found that as more PEVs are added to a neighborhood, and a higher charging power is adopted, "the distribution infrastructure might no longer reliably support the local electricity demand." He also noted the higher demand could shorten the expected life of a transformer.

The electric load profiles used in this paper, including household demand and PEV charging with a 10-minute resolution, are available for download here.

Earlier studies on how PEVs might affect the grid assumed utilities would have some control over when charging occurs, referred to as coordinated charging, which will greatly facilitate PEV integration. Muratori noted that might be true in the future, but not necessarily. His research didn't focus on using PEVs to return a battery charge to the grid to increase the reliability of the electric system. Future research, Muratori said, should focus on understanding consumer behavior to determine charging requirements, and the choice between using Level 1 and Level 2 residential charging equipment.

"Matteo's work raises important issues for a world with increasing electrification of the vehicle fleet, and leaves us with clear avenues for additional research," said John Farrell, NREL's laboratory program manager for technologies. "We need to continue looking at the synergies between electric vehicles and buildings, especially to make sure the grid remains safe and resilient."


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NREL evaluates charging infrastructure needs for growing fleet of electric vehicles

More information: Matteo Muratori. Impact of uncoordinated plug-in electric vehicle charging on residential power demand, Nature Energy (2018). DOI: 10.1038/s41560-017-0074-z
Journal information: Nature Energy

Citation: Research determines integration of plug-in electric vehicles should play a big role in future electric system planning (2018, January 23) retrieved 25 May 2019 from https://phys.org/news/2018-01-plug-in-electric-vehicles-big-role.html
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Jan 23, 2018
Stating the obvious. But then again, it is obvious to electric car drivers, many of whom found this to be the case.

The infrastructure designers may be still unaware. More articles like this, please.

Jan 23, 2018
Charging of electric cars should be free and accessible everywhere possible... malls, offices, parking lots etc... and once the vehicle is so connected the battery should be used as part of the grid to supply and absorb electricity however generated and flowing at the time.

It will be cheaper for power producers to have stored electricity near where it is needed most and as people move from their homes to their work so too does the electrical capacity move with them.

The grid gets to use the cars as their storage and the cars get the juice form the grid for free.

Jan 23, 2018
Charging of electric cars should be free and accessible everywhere possible... malls, offices, parking lots etc... and once the vehicle is so connected the battery should be used as part of the grid to supply and absorb electricity however generated and flowing at the time.

The grid gets to use the cars as their storage and the cars get the juice form the grid for free.


Not sure about free, but owners should be paid for use of their storage capacity.

Every parking spot needs to have level 2 charger so that solar power in mid-day can be absorbed and fed back as needed.

Also, people can't just park and not plug in, that's not being a good citizen. Maybe parking tickets for failing to plug in, or you don't get same compensation rate when you do plug in?

Jan 23, 2018
I think some usage spikes could be mitigated by making charging accessible. Parking garages, schools, grocery stores, wherever you are.
I think parking meters are ready made to become vehicle charging stations

Jan 24, 2018
It is really nice to see 4 positive comments regarding an emerging technology.
Demand control is obviously going to be one part of the new grid. We owned a Nissan Leaf for a year. Plugged it in every night - and topped it up with 5 cents Kwh juice using a level 1 charger. As batteries get better - which they will - and more and more people get EV's, and higher level chargers - you have the perfect blend. A large distributed demand - just sitting waiting to be met - when there is excess power available. An available source of power - ready to fill in the gaps when needed. It makes sense to me.

Jan 24, 2018
Given the average use profile of cars a level 1 charger is perfectly fine.
That more people install level 2 chargers doesn't mean that everyone suddenly needs to charge at level 2 capacities. If you charge over night it would be perfectly acceptable to have a level one charge from a level 2 charger for the overwhelming majority of days.

Whether there would be spikes on weekends is an interesting question (some would go for longer trips which would require more rapid recharge on return, while others would not use their car at all). At the starts and ends of holidays we'd certainly see charging spikes.

Jan 24, 2018
I agree antialias - we never once charged on anything but our level one home charger. There were times when we took the gas car - because the 80 mile range was not sufficient - but 95% of the time it was fine. 200 mile range would have taken that to 99%. The point of having the higher level charger would be more for increasing the flexibility in terms of storing or discharging from the grid. If you have the ability to do it faster - you are more valuable. Battery tech still has a long way to go - degradation is a big issue. We are getting there.

Jan 24, 2018
I have some serious doubts.
EV are generally great (clean, quiet, etc.) but when they will become more common it will start to generate huge problem for all people in cities.
If it will be a suburb with some sparsly stand-alone homes it could be OK.
But in more dense architecture power infrastructure must be throughoutly rebuilded.
Imagine charging at the same parking not few but about dozens of cars..., a city district with hundreds of such parkings... a whole city.
Demand for power will rise tremendously.
Secondly, our power usage is constantly rising even without electric vehicles.
Without new power plants it won't work as well as without new "intelligent" power grid.
Now green energy is too unstable, unreliable and have too low volume in total power generation.
My conclusion is: EV won't be common without revolution in power generation and more important, storage.

Jan 24, 2018
The point of having the higher level charger would be more for increasing the flexibility in terms of storing or discharging from the grid. If you have the ability to do it faster - you are more valuable.


That was why I suggested level 2 chargers, so the grid could draw more power as well as recharge faster. That's what would make all those cars actually useful as grid storage.

Jan 24, 2018
it will start to generate huge problem for all people in cities.

I don't think so
a) cities have public transport - if you really live *in* the city (and not in the suburbs) then you don't need a car
b) even in inner city areas more than 50% of the people who live there have private parking spaces - where private chargrs can be set up (this is one of those things that surprised me, too, when I looked it up)
c) Supermarkets are already starting to put up chargers. Since everyone goes shopping about once a week that would be adequate to keep the rest charged.

The added electricity needed if every car were replaced with EVs is just about 15% more than is generated right now. I guess most every energy grid right now could handle that. Certainly until 2050 - when the full changeover is projected to be done - an adequate upgrade to cover this increased need can be performed

Jan 24, 2018
Secondly, our power usage is constantly rising even without electric vehicles.

Check your sources. In the first world countries energy demand is pretty much flat (and on a decline per person).
There used to be a direct relation between GDP and energy use, but that has been broken in recent years.

Now green energy is too unstable, unreliable and have too low volume in total power generation.

I think you have data from 30 years ago. None of this is true since then.

Jan 25, 2018
Do not worry, it was the electric power companies who made EVs possible in the first place, by funding them through the Electric Power Research Institute and its committees. I was on the Advanced Transportation Working Group in 1986 funding the technologies which got us here today. Musk had the resources to put it all together, but the work had been in progress for decades.

When we got the first EV, they made sure we would have the capacity on our local distribution system, and promised to monitor it to make sure it was up to date. These were power company ideas, and great ones, since they reduce pollution and make power cheaper by better use of baseload units.

Jan 25, 2018
the way the car batteries would work they take electricity to charge from the grid when the power is cheap and below capacity and they give power to the grid when production is not enough or costly. This will help use electricity more efficiently and less electricity will need to be produced from whatever source. The effect is less energy wasted, cheaper, and less harm to the environment from less production. Many more costly/polluting generators can be shut down even though we are using more electricity it is from less wasted power or from cheaper green power

Jan 25, 2018
LMAO...It's beyond amusing to see these Chicken Little idiots proposing "solutions" for that which they are absolutely ignorant.

Jan 25, 2018
"LMAO...It's beyond amusing , . . . "

We do not care sufficiently to scorn you any more. You are just background noise.

I live in 'Quake country and want to be able to produce off-grid if necessary, and need the inverters in battery systems since PV inverters are slaved to line frequency. When batteries are used, their inverters produce the synching signal (Voltage crossovers), putting PV power into the battery system.

Jan 25, 2018
the way the car batteries would work they take electricity to charge from the grid when the power is cheap and below capacity and they give power to the grid when production is not enough or costly.


Well, the Tesla battery installation in Australia seems to be making money with just that approach - so I guess it should work for cars, too.

http://renewecono...g-93955/

Jan 26, 2018
I have some serious doubts.
EV are generally great (clean, quiet, etc.) but when they will become more common it will start to generate huge problem for all people in cities.
If it will be a suburb with some sparsly stand-alone homes it could be OK.
But in more dense architecture power infrastructure must be throughoutly rebuilded.
....nt, storage.

It's funny to see some people think so shallow about the situation, obviously EV'S is not going to POP into full blown immediate mainstream existence right now while i snap my fingers, like everything in life, the infrastructure will be built and improved as the demand increases so stop take the time to think... and realize that it's not just EV'S coming to the market, but there are people planning ahead of the coming revolution, and though it will happen quite quickly, full adaption it won't happen overnight.

Jan 26, 2018
LMAO...It's beyond amusing to see these Chicken Little idiots proposing "solutions" for that which they are absolutely ignorant.


Not as hilarious as you posting in your original sock chest thumping to yourself in the background thinking your echo is from the people outside your little box, only to realize it's your own socks talking back at you,

... you finally found your antigoracle sockpuppet's password again, i guess turDgent along with the rest of the socks is in the washing no... ? :)

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