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Electric Cars Won't Strain the Power Grid
thecarchik writes "Last week's heat wave prompted another eruption of that perennial question: Won't electric cars that recharge from grid power overload the nation's electricity system? The short answer is no. A comprehensive and wide-ranging two-volume study from 2007, Environmental Assessment of Plug-In Hybrid Vehicles, looked at the impact of plug-in vehicles on the US electrical grid. It also analyzed the 'wells-to-wheels' carbon emissions of plug-ins versus gasoline cars. The load of one plug-in recharging (about 2 kilowatts) is roughly the same as that of four or five plasma television sets. Plasma TVs hardly brought worries about grid crashes."
I admit I didn't have time to read the study thoroughly, but:
(a) The study specifically talks about hybrid cars, not pure electrics; the headline is misleading.
(b) Let's take a very conservative estimate and say an electric car draws an average of 10hp when driving. That's about 7.5kw. Let's round that up to 8 for simplicity's sake, and if we assume 100% efficiency, the car needs to spend 4 minutes on the charger for every 1 minute it spends on the road. If we charge it overnight (8 hours), that's 2 hours of driving time, or 60 miles if you average (as many drivers do) somewhere around 30mph - before you have to plug it back in for another 8 hours. And that's in the absolutely best case.
I might be missing something, but 2kw to charge sounds very unrealistic to me.
Yes but plasma TVs replaced CRT TVs.
And I expect there was a rather large switch from incandescent to compact fluorescent globes around the same time - which may have given greater savings than losses from those plasmas....
But what on earth kind of argument is that? Electric cars wont be a problem coz plasma TVs weren't.... How absurd.
Never happened. True story.
Probably because households buying plasma televisions purchase one, maybe two, and they are replacing cathode tube (with shadow mask) televisions which have been consuming electric load since the 1950s. And those plasma TVs are not operating for too many hours (hopefully), never mind that LCD televisions are far more popular. It's not surprising that many people are at least more concerned when typical two-car households each might add the equivalent of 8 to 10 plasma televisions of net new electricity consumption to the grid. Thankfully that consumption should be off-peak, especially if timed chargers and peak electricity pricing are mandated, but the plasma TV analogy breaks down very quickly.
We don't need to worry about electric cars overloading power grids, we're already doing it right now.
You can't possibly say that the rolling blackouts and brownouts of the California power grid are "normal operating procedures" for a power system working within it's capacity, let alone a sign they have any surplus room for recharging electric vehicles.
Just like most working people, the first thing I always do when I get home is turn on my 4 or 5 plasma TVs. Since that wasn't a problem, I'm sure the electric car I buy won't be a problem either!
It may very well not be a problem, but that statement is goddamn stupid. Most of us aren't drawing that much power regularly when you get home.
Breaking Into the Industry - A development log about starting a game studio.
Getting enough of the materials to make the batteries for a significant number of electric vehicles. And then the fact that you have to replace a major and expensive component of your vehicle (batteries) every 3-5 years.
Really? Is that how you use your car right now?
You don't go to lunch?
Go out for dinner?
Run to the corner store for groceries?
Any number of other errands or other trips?
And how many of these trips do you plan far enough in advance to also plan and schedule your car to be charged?
More likely: drive to work for 9 am, park, plugin car and charge [along with everybody else] just so you can get home in it
-oops, going out for lunch, need to charge car again
-drive home
-start charging car right away, because you might decide to go out for dinner or do any number of errands that evening
-do errand and charge car again
Repeat EVERY DAY.
Sleep your way to a whiter smile...date a dentist!
I think the bigger question, which I didn't see answered in TFA, is whether these things are truly better than ICE vehicles on the environment. I mean sure we know they'll probably be better than a Hummer, but has anyone figured out what the mining of lithium for the batteries, the toxic components used in such batteries, the amount of carbon put out in production, the amount used by the grid (many places still have coal plants you know) and finally the disposal and replacement of those batteries after 3-5 years, how all of that compares say to a Kia or other small 4 cyl ICE vehicle?
Because as we saw with the "get rid of teh evil lead solder!" stupidity we can often make things worse instead of better by not thinking things through. in the case of solder we ended up with a lot more e-waste because the crap solder they replaced lead with broke down much faster than the old, and thrown into a burn pit in China frankly isn't any better than the old. So I would like to see what a "birth to death" study of elec VS ICE would show before I say that elec is the way to go. After all it won't be doing us much good if we just trade carbon at the tailpipe for carbon at the plant PLUS piles of dead batteries PLUS lots of waste in mining and disposal. We need to look at the entire cycle before judging one tech or another.
ACs don't waste your time replying, your posts are never seen by me.
I think the major load on the charging systems would either be early morning when you just get to work and plug in, or early evening when you just get home and plug in. Not exactly prime time for brown outs..
My understanding, based on the time-of-use billing coming soon to a power company near me, is that early evening when you just get home and plug in is exactly prime time for power shortages.
You could centrally control when recharging stations activate, but is somebody plugging in at 5:30 pm because they want to recharge it overnight, or because they want to pick up their kids from (band/soccer/whatever) practise at 9pm?
- RG>
Hey pal, this isn't a pleasantforest, so don't waste my time with pleasantries!
In future, it won't be enough to let a consumer make the decision on when to consume and encourage him with discounts in low peak hours. The model should be that for those loads where "time doesn't matter" we (the consumer) can indicate our constraints and then the electricity company will work within those boundaries. Of course, the more lenient the consumer is, the better rate he gets.
For this example, if I park my car at the office I don't care if the battery gets reloaded at 11 am of after lunch. As long as it's done before I drive home at 5 PM. Same for the return trip, the car could be rechared at 11PM or at 3AM, I don't care.
The crucial thing here is that fore heavier, but also time independent loads like this, your utility company gets control over when you are using electricity. We're still quite a bit away from that, but with smart grids, that's the way we're going.
And it will all benefit green power that produces electricity at "unexpected moments".
Browsers shouldn't have a back button!! It's all about going forward...
Some blokes put out a leaflet, so now your asshattery shall be ignored? 'Fraid not!
First, assuming constant total wind over the globe, keep in mind there's essentially no wind generation on the oceans -- as more or less of that total constant wind is in the middle of the Pacific, it alters the total available on land.
Second, electrical grids are more-or-less continental in scope, at most. This means that summing the wind over one continent together with the wind in another continent is totally useless for the available power in either continent; when it's blowing harder here, and weaker there, we have a surplus of capacity, and vice versa. It's uneconomical to deliver power across oceans, so you'll just have to fire up some local peak plants.
So you're quite simply wrong before; fortunately for Mark Diesendorf's credibility, that paper you linked says nothing to support you.
Now as for what it does say... did you even read it? They said to match an 1GW base-load plant, you need about 2.6GW of wind, plus a peak-load plant to cover low-wind periods. And you offer that as a refutation of the GGP's suggestion that you could use electric vehicles to take advantage of surplus power when wind (whether at a single site, or summed across several sites) is above average, and reduce the need to switch on peak plants when it's low? Staggering.
...will the invention of the train use up all the coal supply? Another question: will the invention of the car use up all the world's oil supply? Which is more plentiful: oil or solar (which causes wind)?
Society use your Sciences
Large flywheels and reverse pump hydro plants are the grid scale batteries of choice, in fact I expect there will eventually be flywheels for midsized power consumers like small datacenters in the future to take advantage of cheap offpeak power (this is sometimes done today using frozen block chillers).
There are 4 boxes to use in the defense of liberty: soap, ballot, jury, ammo. Use in that order. Starting now.
My meter makes no differentiation between day and night, simply usage.
Removing lead is progress and in time the restriction will become a non-issue for even those that believe in the goodness of lead.
In the US, people spent ages bellyaching about the low-flush toilets. Initially the toilets that came out often did perform poorly because when you could use half a lake to flush the toilet you didn't need good design. Designs have improved and one of the greatest wasters of fresh water was reduced.
Realize that government is a process and that there are always trade-offs. Usually they aren't even entirely clear trade-offs.
man, I'm not an expert, but 99.8% of battery charge / discharge efficiency looks like a total BS to me. 1) that would mean, that only 0.2% of electricity used to charge the battery changes to heat. and that is not right, battery pack in hybrids and electric vehicles have cooling. and you don't need cooling for 4kW * 0.002 = 8W of heat produced. it may work for charging with tiny little currents, but you don't wont to charge your car a whole week. 2) you are forgetting the efficiency of charger. and it would be around 80-90%.
No. Rather, if they think there's a reasonable chance that they will occasionally need to drive further, they will obviously decide that an electric car isn't for them.
Just like if most of the driving will be one person, but they will need to occasionally carry four, a two-seater is simply eliminated. People base their decision on reasonable maximums, not average use. It's not "hate against 'green tech'". It's just an absence of irrational infatuation with it.
Still , as someone pointed out , statistically , it's very likely that electric cars will charge at night , as most people will be working in the day , and will have to recharge there cars when they get home in the evening.
Hmmmm. What about a company perk of being able to charge your vehicle at work? That would seem to be a great incentive to get people into EV's in the first place (ie make it a non-taxable perk to charge at work).
Eclectic beats from Leeds, UK
handmadehands.co.uk
You were being funny, but I think it's important to point out: we produce about 14 exajoules of energy for electric power a year. We use about 28 exajoules for transportation.
This study seemed to overlook something rather important.
Although you have a strong point here, the energy we need for transportation would go down. We would use less if we used the much efficient electric cars. Gasoline/diesel cars produce loads of waste heat.
I believe there are still serious concerns with deployment strategies that put all of our eggs in one basket. Loss of power on the grid as we've seen in the past is crippling. Compound this with the loss of personal transportation is stupefyingly arrogant to pursue. Consider the grid has been in existence for 50 years and was state of the art at the time of its inception. Neglect has set in and expansion is hindered by epic proportions of environmental and bureaucratic red tape. So the question becomes, do we wish to place additional burden on this aging infrastructure without mandating updates and infrastructure improvements? Given the crucial nature of those arteries it seems foolish to run them to capacity all day every day. It's an issue that deserves fudge factor in favor of over engineering. It's also important to understand that the infrastructure and the power generation facilities are two different entities to consider. Power generation facilities from an operations perspective operate at a higher efficiency and reduced maintenance if they can be operated at a constant load. It can take hours to respond to large power loading as commissioning and syncing generators is no small task. Thus continuous load would improve their operations. The grid on the other hand is an aging infrastructure with increasing demand and load. It's capacity and lifespan are finite.
No single raindrop believes it's to blame for the flood.
But latest plants doesn't really matter that much. Most of the plants are still old 40-45%. Yes in 30 years, we can talk about average 60%, but not now. Second thing, around 50% of electricity in US are produced in less effective coal plants. And if you put the numbers together (with 45-50% for power plant efficiency), you will get something around 30-35% That is exactly same as hybrid. btw any sources for the petrol / diesel efficiency numbers? thanks
Looking at the actuals vs. the predicted costs in the graph you linked, they underestimated by 30%. Maybe they were just having a bad day.
If the electric cars go home and charge at night, no, they won't strain the grid. Power is overproduced at night (you actually can't spin down the generators all the way, so they produce power even if nobody wants it.)
What I read in IEEE spectrum a few months ago was that it wasn't the production capacity that would be strained, but the transformers in residential areas. This surprised me, but the article stated that in many areas, the cooling capacity of the local transformers was undersized since they would be underutilized at night and would therefore cool off at that time.
That seems strange to me, since in the temperate climes, the hottest part of the year also has the shortest nights -- I wouldn't think the cooling benefit of lower usage at night would be so great, and it's not like your gonna swap out transformers on May Day and Halloween and ship them to the other hemisphere on an exchange program. I also don't think that this is a common practice in my part of the US because my Dad was a power EE, and he talked to me a lot about his job and never once mentioned this. They had a lot of transformer problems: squirrels grabbing two terminals, birds building nests (it's nice and warm), wrong oils used in filling them, PCB remediation, guys at the fiberglass plant busting the nearby insulators with glass beads shot from slingshots. But I sure don't remember anything about undersized radiator capacity. Hardly proof -- and maybe things changed since -- but it makes me skeptical.
I am not a crackpot.
People won't pick a car with the same performance if a more powerful option is available, marketers know that and will will bolt high kW motors in given the option. Saying but you can achieve the same performance with a lower power engine appeals to greenies only. End result, high load on the grid.
Ah, so nobody buys the V4 Accord, V4 Mustang, or any other car with a more powerful engine available?
He's giving LED more time to catch up to CF in initial investment price because of the HAZMAT issues with CF bulbs....
I have worked as a utility electrical engineer. Let me correct and clarify your points. There is no meaningful amount of storage on the electric system (the few locations with pumped hydro and compressed air energy storage (CAES) excepted). The energy consumed (plus losses) is always equal to the energy coming out of the generators. There is no "grounding" of energy (whatever that means).
Energy balance is maintained by different mechanisms for different timescales. For essentially instantaneous (sub-second and second level) variations, energy balance is maintained by the inertia of the generator turbines. The turbines slow down and speed up by tiny fractions of a Hertz when the load changes.
For minute level variations, the mechanical governors of certain plants increase or decrease mechanical power input to maintain energy balance. These plants are designated ahead of time as "regulating plants" (either through an "ancillary service" market in deregulated areas or by the utility's choice in non-deregulated areas) and typically have a high ramp rate (they can change their output quickly). These plants must be online and must maintain their nominal output below their maximum output so they can ramp up and down.
For variations on the order of 10 to 30 minutes, the energy system requires reserves. Reserves are classified as "spinning" and "non-spinning." Spinning reserves are connected to the system and can raise or lower their output by significant amounts in the given time period. Generators providing spinning reserves also often provide regulation services. Non-spinning reserves are generators that have not started, but can be started and connected to the grid quickly. These are typically gas turbine plants that can start up quickly.
For variations on the order of hours to days, a market operator or utility manager solves what is called the unit commitment problem. This problem takes into account start up times and costs, shut down times and costs, operation costs, etc. to determine which generators should be running at all times for the projected load profile.
Voltage regulators and capacitors do not buffer real power variations and do not provide storage. Rather, they are used to maintain desirable operation of the electric system (for instance, keeping the voltage profile close to its nominal value).
Hopefully this helps.
The other problem I see more of than whiskers post RoHS is cracked BGA joints. It is especially bad in equipment that is cycled often since the PCB and package have different thermal coefficients. The Pb allowed the solder to flex more, all the flow and corrosion issues have been fixed now as everyone learned the differences though.