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Full of promises about saving the Earth and conserving energy, could automakers and visionaries be missing one big thing?

Even though automakers and environmentalists are pushing new electric and hybrid electric cars, claiming less pollution to make our Mother Earth unhappy with our wasteful ways, it seems they come with demons of their own. Well, maybe not so much.

The media has certainly been filled with talk of the cleaner cars lately. Everything from MIT's City Car to the Lightning Car Company's 700HP sports car to Chevrolet’s Equinox fuel cell SUV which DailyTech got to take for a little spin this January. What's the deal? Well, obviously if you have cars running on electricity, they aren't churning out megatons of air and water pollutants each year. Well, the cars won't be, but the whole "where does the power get made to power the cars then" quandary can be fought with later.

Today we'll make note of a much stranger side effect of all these silent, battery and (noble) gas driven people movers. From the University of Texas at Austin comes research projecting that there's going to be a pretty large quantity of one of our most precious natural resources gobbled up by these electrics. No, it's not oil, trees, hydrogen or even indium - we're talking about water.

It's not much of a shocker, it's true. Water is probably our most precious resource, but barring evils like pollution and hydrolysis, it's one of Earth's most abundant and easily renewable. So we make a bit more steam, what's the big deal, right? Let's let the research speak for itself for a moment.

We compare figures from literature and government surveys to calculate the water usage, consumption, and withdrawal, in the United States during petroleum refining and electricity generation. In displacing gasoline miles with electric miles, approximately 3 times more water is consumed (0.32 versus 0.07–0.14 gallons/mile) and over 17 times more water is withdrawn (10.6 versus 0.6 gallons/mile) primarily due to increased water cooling of thermoelectric power plants to accommodate increased electricity generation. Overall, we conclude that the impact on water resources from a widespread shift to grid-based transportation would be substantial enough to warrant consideration for relevant public policy decision-making. (PDF)

Wow. 10.92 gallons of water per mile. It's a pretty staggering number. Thinking that my daily commute used to be about 40 miles, not including zipping around town for random things, that's more than 400 gallons in one day. That's probably more than the average person uses all week between hygiene and self hydration.

On the whole the conclusion they come to isn't exactly life-threatening, but it could become a problem, as they point out, for areas where water shortages are already experienced yearly.

In reality, a study like this doesn't really say much about how much pollution we can or can't stop by converting to electric person delivery, other than the inflated power generation, and subsequent water requirements, that will be needed to charge all these cars (we weren't going to talk about that though). But it does point out a much simpler fact that though we may think we're heading in the right direction by cutting down our toxic pollution output, sometimes we forget to think about the simple things we might be sacrificing on the way.

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By pauldovi on 3/12/2008 10:00:35 AM , Rating: 2
~11 Gallons per Miles seems a little ridiculous to me.

I think the best thing in the direct future is small diesel motors with a electric motor and a battery / capacitor bank to store the energy.

As we move into the future, who knows what the solution will be. One this is for sure, it won't be hydrogen. Hydrogen will always be the fuel of the future. It takes way to much energy to get hydrogen fuel.

RE: Really
By ChronoReverse on 3/12/2008 10:23:14 AM , Rating: 5
The water is used for cooling. It's not like it DISAPPEARS.

RE: Really
By Master Kenobi on 3/12/2008 10:40:35 AM , Rating: 1
But it has to come from somewhere. In a time when we are already strapped for water in many areas (especially during the summer), this will take more of that water out of use by everyday people. I suppose the solution to this is to pump in ocean water and purify it for regular use. Will still likely need to pump water across country though for states that don't have easy access to ocean water.

RE: Really
By bighairycamel on 3/12/2008 10:49:42 AM , Rating: 2
But it has to come from somewhere.

Yes but the 10-11 g/mi factors in water used for cooling, which would be in a closed circuit being recycled over and over again. Sure an occasional top-off would be needed and a rare flush-and-fill, but minus this water used for cooling the number probably drops to something much more negligable.

I highly HIGHLY doubt the vehicle is consuming (a far different definition that using) 10-11 G/mi.

RE: Really
By pauldovi on 3/12/2008 11:41:40 AM , Rating: 2
Closed Circuit? What is going to cool that hot water?

Typically rivers are circuited through power plants and back out to the regular water.

Would be great if hot water supply came from Power Plants. :)

RE: Really
By TheWizardofOz on 3/12/2008 12:07:35 PM , Rating: 5
Ever heard of the term "radiator" ?

RE: Really
By Chris Peredun on 3/12/2008 1:10:53 PM , Rating: 5
Barring being arrested for violating the laws of thermodynamics, I imagine some of the heat could be recaptured and used to generate further power.

RE: Really
By stephenfs on 3/12/2008 1:43:22 PM , Rating: 3
A wise man once said, "In this house we obey the laws of thermodynamics!" -Homer Simpson

RE: Really
By Hoser McMoose on 3/13/2008 2:24:36 AM , Rating: 2
The wording might be a bit off, but if I understand the previous poster correctly there is no violation of any laws of thermodynamics here. Essentially capturing some of the waste heat is what a combined cycle thermoelectric power plant is all about. Pretty much all new natural gas and some new coal power plants use this concept.

The trick is not to get energy from nothing, it's just to raise the efficiency of energy conversion from ~30% up to ~40 or even 50%.

More energy converted to electricity means less energy wasted in heat and therefore less water needed to cool the power plant (not to mention less fuel and pollution).

RE: Really
By Captain Orgazmo on 3/13/2008 6:12:36 PM , Rating: 2
Oh yeah, great. Radiate all that extra heat back into the atmosphere, warm the planet, kill the seagulls, kill your kids. Why not just start carpet bombing our own cities right now?


RE: Really
By DragonMaster0 on 3/12/2008 7:27:17 PM , Rating: 2
Closed Circuit? What is going to cool that hot water?
How does a watercooled PC work?

RE: Really
By KristopherKubicki on 3/12/2008 8:48:42 PM , Rating: 2
Cooling your processor is not the same as cooling a nuclear reactor core. There are considerably different technologies of scale.

RE: Really
By Mitch101 on 3/13/2008 11:02:04 AM , Rating: 5
There goes overclocking a nuclear reactor.

Maybe thermaltake will come up with a nuclear reactor cooling solution. Fan noise might be a problem.

RE: Really
By geddarkstorm on 3/12/2008 11:33:59 AM , Rating: 3
And it has to go somewhere too. That water used for cooling can be piped right back in to circulation. Even if it's turned to steam, you have condensers to recapture most of the water.

Nonetheless, it is true that water supply must be kept in mind at all times when evaluating what technologies are practical to pursue, but I don't think it's such a "doomsday" sounding problem as the research sounds first glance.

RE: Really
By clovell on 3/12/2008 5:58:37 PM , Rating: 2
> These increases in water usage represent approximately 0.2–0.3% (28) and 3% (27), respectively, of overall U.S. water consumption (100,000 Mgal/d freshwater in 1995) and withdrawal (408,000 Mgal/d in 2000)

From the manuscript.

RE: Really
By Grast on 3/12/2008 10:52:40 AM , Rating: 5
I believe the report is referring to the water use for all types of electrical generation. All forms of electrical generation are basically large steam plants with the exceptio of gas turbines. The fuel used to create the heat can be coal, oil, nuclear fission, and possibly fusion.

All of these technologies take huge amounts of water. Nuclear plant use vast quantities of water in evaprative towers.

Nuclear is the future and modern designs on the coasts can greatly reduce the requirement for large quantities of water by using sea water as the coolant for the secondary steam plants. I digress.

The main point of the argument is that energy generation is not very environmentally friendly no matter how much we try. Until Star Trek style energy becomes available, we will always be threading the needle between electrical generation and the polutants it generates.


RE: Really
By jRaskell on 3/12/2008 12:21:18 PM , Rating: 2
The gallons withdrawn is a bit misleading. The report referenced explicitly states what is meant by consumed and withdrawn. To quote the report directly (link available in the article)

"Water withdrawal pertains to water that is taken from a concentrated source, used in a process, given back from whence it came, and available again for the same or other purposes."

I do think the information provided in the report is valid, and should certainly be a consideration, but I don't see it as a concern except maybe for locations that regularly deal with substantial water shortages. The water required for these processes does not need to be drinking water. The Hoover dam obviously has a HUGE water withdrawal figure, but I seriously doubt it has any bearing on general water availability in that area. If anything, the huge lake that dam created likely has a positive affect on water availability in that area.

RE: Really
By Ringold on 3/12/2008 3:44:12 PM , Rating: 2
My home state of Florida is and has been furiously trying to secure future sources of water; county governments on the east coast did a study and found a desalination plant is now their most cost-effective option.

I've heard California is having its water problems, and Georgia Conservatives sounded like they were about to form their own militia and storm the Army Corps of Engineers at Lake Lanier to stop the flow of water being sent here to Florida.

I don't know about Texas, New York or Ohio, but Florida and California right there means a huge portion of the US population lives in an area experiencing acute water shortages.

If they could use salt water, then no problem.

RE: Really
By boogle on 3/13/2008 8:20:46 AM , Rating: 2
I think the best thing in the direct future is small diesel motors with a electric motor and a battery / capacitor bank to store the energy.

Why? The car is heavier, has dirty great lithium ion batteries (not the most environmentally friendly) and a fossil fuel engine. MPG can only go down, even if it's just due to the added weight. But converting energy is never 100% efficient, so the conversion of energy from the diesel engine to the batteries, and then from the batteries to the electric motor, and then from the electric motor to the wheels is just asking for lower MPG.

Hybrid cars are thoroughly pointless from an increased efficiency perspective. They're great for moving pollution out of urban areas, but other than that they're not much different from a normal car. Their MPG figures are only better (in the US) because they have more efficient fossil fuel engines than the vast majority of US vehicles.

RE: Really
By kkwst2 on 3/19/2008 5:15:47 PM , Rating: 2
Well, that's not strictly true. I would agree that in their current design (both drive the powertrain directly) they're not very useful. However, a hybrid in which the diesel charges the battery and electric motor powers the wheels is much more efficient than just an ICE. There are designs coming out like this, one I think from Chevy. If the ICE can run at one RPM it becomes significantly more efficient.

RE: Really
By Darkskypoet on 3/19/2008 11:01:51 PM , Rating: 2
Additionally, and I don't have figures, but i am sure someone does, the ability to use generators in wheel hubs to drive and brake the vehicle is a definite advantage.
(Yes I know most are done through transmission still)

Especially considering standard ICE vehicles simply dump their momentum to heat, friction, noise, etc. Regenerative braking, is one of the best parts of a hybrid / electric design, and is one of the reasons why Hybrids have much better city mileage, then standard ICE's. Further, the ability to simply cut the engine out in a lot of stop and go situations further adds to the 'in-city' benefit.

Highway driving, and efficient Freeway systems do negate the advantages of a Hybrid considerably, I would even say it probably turns the Hybrid into something more inefficient then an ICE. However, for many cities experiencing grid lock regularly, the small generator / wheel well type electric motors should give better AWD handling, great regenerative braking characteristics, and a much more efficient drive for stop and go traffic.

The weight increase should also be quite low, considering you would lose the need for a heavy main drive train / transmission, and instead have a small ICE as generator, and 2 or 4 electric motors, depending upon design. As well if well designed, you may also lose the need for the heavier cooling systems / hydraulics standard in many cars. However, I am uncertain as to that point.

Clearly, there are better hybrid designs available then those utilizing a FULL ICE System and A FULL Battery system shoehorned into an ugly vehicle. (*cough* Prius)

11 gallons/mile off
By MadMaster on 3/12/2008 3:11:07 PM , Rating: 2
Assuming it's from a coal power plant, and the vehicle gets .25-.5 kwh per mile (my experience when driving electric vehicles) and electricity costs .5 gallons per kWh. 11 gallons/mile is WAY off.

Here, the government says the number of gallons evaporated per kWh is .5.

1 kWh will get a electric vehicle 2-4 miles. We'll assume it's 2 and .5 kWh per mile. That's .25 miles/gallon.

Your numbers are off BADLY! Is it because you guys included total water (which is not all waste and gets injected back into a lake or reused) instead of evaporative water?

RE: 11 gallons/mile off
By EglsFly on 3/12/2008 5:39:51 PM , Rating: 2
I agree, this article is misleading.
There is no way that amount of water is being "consumed".
First of all, power plants which use water for cooling, steam generation and such, draw in lots of water for these purposes, HOWEVER, much of the water is recycled over and over again, and what is not, is either sent back to the earth via evaporative coolers or discharged into lakes, rivers, and creeks.

RE: 11 gallons/mile off
By Grast on 3/12/08, Rating: 0
RE: 11 gallons/mile off
By ElFenix on 3/13/2008 11:12:14 AM , Rating: 2
especially if the water is drawn out of a fossil aquifer which isn't recharging. even recharging aquifers are being drawn down.

RE: 11 gallons/mile off
By bfonnes on 3/12/2008 8:14:12 PM , Rating: 2
There seems to be some kind of bias against any technology or science that is environmental in nature on Dailytech, so I just have come to expect articles like these. I just read them for the crazy debates and to see an opposing point of view even if it seems outrageous. Anyway, I don't know if it's an agenda by the editors or if they just don't pick their bloggers very carefully. Good journalists are hard to find these days, aren't they? You need to be willing to both stick your neck out AND tell the truth. Sticking your neck out for no other reason that to stick it out is what those manning the guillotine used to expect from it's patrons.

RE: 11 gallons/mile off
By bfonnes on 3/12/2008 8:17:39 PM , Rating: 2
In other words, why don't they just stick to what they do best and that's tech... Here's my opposing view point... Try to liquidate emissions from current cars and drink that compared to what you would get from a hydrogen powered car if you have any debate about it's environmental consequences...

The biggest possible environmental consequence from hydrogen cars isn't the half-baked ideas in this article... It's battery disposal.

RE: 11 gallons/mile off
By bfonnes on 3/12/2008 8:20:24 PM , Rating: 2
Besides, if the power grid becomes decentralized like it inevitably will be if we aren't expected to all be government welfare projects in the future, then nothing in this article makes any sense. Look to the future and not the past!

RE: 11 gallons/mile off
By KristopherKubicki on 3/12/2008 8:44:07 PM , Rating: 2
Besides, if the power grid becomes decentralized like it inevitably will be

How do you propose this? Solar panels on everyone's houses? What about factories and such? I don't think that's an inevitability or even feasible right now. If anything, with technologies like fusion and hydroelectric, we're *more* centralized -- especially since not a lot of people want a power plant in their back yard.

RE: 11 gallons/mile off
By KristopherKubicki on 3/12/08, Rating: 0
RE: 11 gallons/mile off
By MadMaster on 3/12/2008 10:09:45 PM , Rating: 2
Er, I re-read it. It says 10 gallons drawn. I find this misleading because only .5 gallons/kwh is evaporated, the rest of the water is reused or re injected to the river/lake (little impact on the environment except for heat pollution, but that is another small issue...).

The .5 gallons/kwh evaporated translates to 138 gallons per second at a 1 GWh power plant (coal or nuclear, both use similar steam turbine technology).

You can condense the water after running it through a steam turbine. The downside is that the steam turbine looses efficiency (because turbines work on a pressure differential), and the system is more complex/expensive. Such are the trade offs when engineering a power plant that uses steam.

Someone mentioned decentralized power. This makes A LOT of sense. An example of this is a combine cycle gas turbine. What they do is use the expanding hot gases (like a jet engine) when burning natural gas to turn a turbine(usually they are in the 10-100MW range). Then, it uses the hot exhaust to heat water which is in turned used to heat buildings. These systems are extremely efficient, hitting something like 80-90% efficient (compared to about 40% at a comparable coal or natural gas fired power plant). Systems like this are already implemented in many places.

The idea with this decentralization is to put one of these turbines every few blocks, circulate hot water, and generate electricity (btw, natural gas burns extremely clean). No need for a complex/expensive grid or extremely high heating costs...

By Spivonious on 3/12/2008 11:39:44 AM , Rating: 2
So the electric plants boil water using various fuels to generate steam which spins the turbines which generates electricity. The steam is then captured, cooled, and fed back into the process. Providing the additional electricity needed for these cars will cause a need for more water, but only for the new turbines that are brought online to provide the increase in output.

I think this whole "concern" is ridiculous. Even if we do consume more water, the Earth is made up of over 70% water; I doubt we'll run out anytime soon.

RE: Steam
By Fridayalex on 3/12/2008 11:52:12 AM , Rating: 2
I think this whole "concern" is ridiculous. Even if we do consume more water, the Earth is made up of over 70% water; I doubt we'll run out anytime soon.

I take it they will need fresh water to run on. The oceans contain 97 % of the earth's water while the remaining 3 % is classified as freshwater. Seventy-seven percent of this surface freshwater is stored as ice and 22% as groundwater and soil moisture. The remaining freshwater, making up less than 1 % of the world total, is contained in lakes, rivers and wetlands. I can see how this might eat into what fresh water is left.

RE: Steam
By Spivonious on 3/12/2008 12:05:24 PM , Rating: 2
True, but wasn't there an article on here recently about wind-powered desalinization?

RE: Steam
By Hoser McMoose on 3/13/2008 2:50:09 AM , Rating: 2
I take it they will need fresh water to run on.

Nope, an awful lot of power generation makes use of sea water for cooling purposes. Obviously though this is dependent on location.

At least one power plant in Arizona makes use of treated sewage water for it's cooling needs, a rather nifty solution.

RE: Steam
By Grast on 3/12/2008 5:48:02 PM , Rating: 2

The key issue in your statement is COOLED. How do you cool high temp 3000 psi steam which has just left a steam turbine.

1. You can send the steam to huge evaporative coolers. Fresh water is then used to cool the steam back into water. This is the method for most nuclear plants. This method uses large amounts of water.
2. You can have a secondary loop which uses a cool water from an alternate source to cool the secondary steam loop. This has issues because if you use a fresh water source. The plant can litrally boil the body of water.

Water is key in all power generation except gas turbine. Coal plant are not that bad because they use low pressure steam turbines and simply exhast the steam into the air. Nuclear plants need either tons of water for evaporation or a cool body of water... such as the ocean.


What about public transport
By Flunk on 3/12/2008 12:34:41 PM , Rating: 1
What if instead of using horrifically wasteful private transportation, the switch to electric vehicles is done with a switch to more efficient public transit systems?

Just because we do something one way now does not mean that we have to do it that way. Feel free to mod me down if you are scared of change.

By Chris Peredun on 3/12/2008 1:15:27 PM , Rating: 3
How would you propose the 25% or so of the population of North America that live in rural areas get around, given the absence of anything resembling public transit in such regions?

RE: What about public transport
By djc208 on 3/12/2008 2:01:10 PM , Rating: 2
I think you'll see more of a push toward public transport but only where it makes sense: in more poulated areas and cities, and for longer trips that many would do in a vehicle now.

Even then it's got to make sense. Right now it's both cheaper, quicker, and less cumbersome to drive my car to work than ride the bus, and I only live 5-miles from work.

If cable companies can't be bothered to run a wire out to most rural areas of the US, what makes you think soneone is going to run more expensive train/subway/bus lines.

RE: What about public transport
By Spuke on 3/14/2008 5:13:07 PM , Rating: 2
Feel free to mod me down if you are scared of change.
I'd rather berate you for not understanding how todays world works instead of rating you down. But that's just me.

Problem solved
By jackedupandgoodtogo on 3/12/2008 3:08:49 PM , Rating: 2
The government needs to mandate a new public transportation policy. I'm not talking buses and trains. I'm talking upgrading our roads and freeways with power conductors and computer guidance systems. Make all vehicles electric cars that run off a separate power grid and controlled by a computer network. Hands-free driving from start to destination, reduce traffic congestion (major waste of energy) and accidents, and yet still provide for off-the-grid control of the vehicle (manual override). Power can be centrally generated specifically for this application (ie. off the main power grid for consumers) and the vehicles would have batteries so that they can run even off the grid. It would charge on the road.

This system would solve a LOT of problems. No more getaway ability for crooks, tracking politicians who visit prostitutes, traffic congestion a thing of the past, etc. :)

This is what I envision as the future of public transportation. Especially if I don't have to drive in traffic with the lady putting on her makeup or the guy talking on his cell phone, neither paying any attention to their driving.

RE: Problem solved
By Hawkido on 3/13/2008 1:51:30 PM , Rating: 2
Great now they won't have to hack my pacemaker, they can just hack my car and cause a Massive pileup. Thanks man!

RE: Problem solved
By jackedupandgoodtogo on 3/13/2008 6:20:07 PM , Rating: 2
Eh. Everything's been hackable. There's never been a device made that couldn't be hacked, whether digital or analog or mechanical.

RE: Problem solved
By Spuke on 3/14/2008 5:14:50 PM , Rating: 2
Eh. Everything's been hackable.
I would rather NOT have my car hacked in the middle of a drive. You are, of course, free to go do that.

By Spyvie on 3/12/2008 12:23:22 PM , Rating: 2
I'm not sure about these water usage numbers, and I'm absolutely certain the earth is not going to run out of water.

What about ozone pollution from all the electric motors that may eventually be crowding our streets. It may not be emitted in anything like the quantities of emissions from an ICE, but ozone is a particularly nasty pollutant and already reaches dangerous levels in big cities without a bunch of electric cars running around.

I think it could be a problem for some dense urban areas.

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