PHEV vs. EV

[plugmein2]

In researching my Prius to be converted to plug in, I was confronted with the idea of stricty going EV. I had a guy in Utah who takes old VW Bugs and Chevy Geos and takes out the ICE (Internal Combustion Engine) and makes it strictly an EV for about $8,000. He stated I could use the EV for commutes (about 40 miles round trip) and use my gas car for long road trips. hmmmm.

Yes,.... but the plug-in Hybrid gives me two cars in one!! EV for short trips and hybrid mode for long. It seems to me the EV has to be able to bridge the range gap or something.

I am an advocate for EV because electricity from the grid is much cleaner and cheaper than out of the tail pipe, and recently, power plants have been hit by the EPA with providing cleaner energy.

Here in UT, 85% of our power comes from coal because we have so much of it. However, we have one of the cleanest coal burning plants in the nation.

I am also excited about Plug-in Hybrids but car manufacturers are dragging their feet. See the quote from a Toyota rep.:

"We don't have all of the information but several news reports suggest the critical resource is the availability of batteries. Last October, our Georgetown KY tour group was told that batteries were limiting Camry hybrid production. The problem may be that building one plug-in Prius and a gas-only Camry takes the battery resources needed to make two regular Prius. Then there is a the problem of managing user expectations.

So I'm content to wait a bit, to let the technology mature. But compared to the fool-cell technology, plug-in has a lot more credibility. In the short-term, consider a 'do it yourself' plug-in.

Bob Wilson"


Well, it looks like PHEV conversions are here to stay for a while. Unless you want an EV.

What do you think?

JOANNA

[JimN]

For $50000 buy a new RAV4ev that goes 100 miles or wait until a purpose built EV with acceptable range is affordable. On a long trip the extra batteries in the PHEV are dead weight once they discharge. I believe the PHEV conversion market will continue even after they are offered by the manufacturers.

[MJFrog]

Originally Posted by JimN

For $50000 buy a new RAV4ev that goes 100 miles or wait until a purpose built EV with acceptable range is affordable. On a long trip the extra batteries in the PHEV are dead weight once they discharge. I believe the PHEV conversion market will continue even after they are offered by the manufacturers.

[Bold added] You have a point there. I don't make many cross-country trips, or even trips longer than 60-80 miles at a time. The few times I do, I should be able to remove the battery pack in a reasonable time, cap the wires, and drive as a standard hybrid.

[plugmein2]

"On a long trip the extra batteries in the PHEV are dead weight once they discharge."

LOL! How many times have we had dead weight in the car on a long trip that wasn't batteries. I think I would prefer taking the batteries. Heehee.

Besides, once you reach your destination, you may have the chance to recharge.

JOANNA

[wfolta]

Originally Posted by plugmein2

I am an advocate for EV because electricity from the grid is much cleaner and cheaper than out of the tail pipe, and recently, power plants have been hit by the EPA with providing cleaner energy.

From what I've read, unless you're in the Pacific Northwest, which has a lot of hydroelectric, you're putting out as much pollution with an EV (from the power plant) as you are from a Prius.

"Clean Coal" is relative to "Dirty Coal". If your main concern is pollution, I'd suggest getting real numbers -- there are a few threads in these forums that have mentioned numbers in the past -- and look closely. Until solar/wind/wave/etc are widespread, you may well not be reducing pollution at all, and you'll lose the flexibility of a hybrid over an EV.

[richard schumacher]

Converting Prius to pure EV would be silly, a complete waste of the expensive hybrid parts. If you want an EV, sell the Prius and buy a new purpose-made EV, or buy a used Bug or Geo and have that converted. That way someone else will buy your used Prius and it will replace something with poorer fuel efficiency.

The specific question about CO2 is, how much coal does your electric utility use? If it's more than about 50% then an EV will create more CO2 than does a Prius. If you have the choice of getting 100% renewable electricity that would be far and away the most effective pollution reduction measure you can take even if you don't get an EV or a PHEV. If you're stuck with 85% coal electricity then you should keep the Prius as it is *without* a plug-in conversion, and *not* get an EV.

[mrbigh]

Originally Posted by plugmein2

"On a long trip the extra batteries in the PHEV are dead weight once they discharge."

LOL! How many times have we had dead weight in the car on a long trip that wasn't batteries. I think I would prefer taking the batteries. Heehee.

Besides, once you reach your destination, you may have the chance to recharge.

JOANNA

Talking about carrying dead weight and PHEV batteries.
In my last trip to Madison, Wisconsin for Hybridfest 2007 I covered a little over 2000 miles round trip, full PHEV with 3 extra TOYOTA NiMH packs plus all the amenities of a trip for 2 people (my wife and I) for 7 days plus a show tent and a 36" LCD for technology presentations during the event, the vehicle was full and heavy.
I recharged my PHEV Prius 15 times (thanks to rest stops and service stations courtesy) in this round trip, 2.5 to 3hs recharge time each time and made an averaged 82MPG in the total trip from Long Island,NY to Madison, WY.
Let me tell you that there is not a dead weight in a PHEV if you know how to take advantage of what you have.
By the way, I won the BEST car in Show at Hybridfest 2007 for technology and appearance

[vertex]

I got interested in the Prius when I was thinking about making an EV conversion. I ran into several problems, that the Prius solves. One major one is the regen/braking operation. The Prius solution is elegant. Another is AC, only the hybrids have electric AC. Power steering can be another problem, not many cars have electric power steering, or you can find a few cars without power steering. The Prius came up as the best solution. Then I thought about removing the ICE, and putting in another electric motor, (MG3). Then I thought about all the headaches of making the computer think the new MG3 was the ICE. Then I got the idea of leaving in the ICE and adding rear wheel drive with MG3 (and MG4?) with a seperate power system, and some kind of servo, so the Prius mostly thinks it is going slightly down hill when being pushed by the rear wheels. This gets around all the sillyness of having to turn off the car to go from pure EV mode to normal mode, plus I would have the fastest Prius ever! Thats having your cake and eating it! Of course, when the batteries SOC gets too low, I can always continue driving as a normal Prius seamlessly.

[DaveinOlyWA]

an EV only option only works if you can afford to have another car for longer trips. until i got my 2010, we had an EV that only did very short range trips (30 miles tops and with lead acid batts it was recommended to not discharge below 40% on a regular basis, so effective range was actually around 15 miles) mostly commuting to work 7 miles one way. i do plug in at work, so i run on the top of the pack only.

until we have companies like Better Place putting out public charging stations, neither plug ins or EV's will do much. now with 100 mile EV's on the horizon, that will make a greater market, but only for people who have the extra money to run two cars. as it stands, without being able to plug in away from home and not being able to double your range, it will simply not work financially for many people.

now, plug in kits are becoming more popular and competition, better charge storage options, and just better knowledge, period will make that option more affordable.

[chogan2]

I have the Hymotion conversion. PHEV is very good for people who mostly drive around town. In that case, you can substitute electricity for gas for a large portion of your transport.

For an EV conversion at just $7K or $8K, you'd better ask if you're getting lead-acid batteries. If so, a) they are heavy, and b) you'll replace them every few (say 3) years, at fairly substantial cost, if you use the car regularly. Over a vehicle lifetime, that's going to be a pretty substantial cost in money and natural resources.

Here in Virginia, with about 50% coal-fired generation, my fairly exact calculation is that the electric miles in the PHEV reduce C02 emissions by just 30% relative to standard (gas-powered) miles in the Prius. That's based on 4 miles per KWH, 46 miles per gallon gasoline, charging off the grid, where Va Power generates an average of about 1.2 lbs of C02 per KWH. It's not even completely clear that I'm getting 4 miles per KWH, but that's what the US National Labs tests showed as average. One user here measured it and was getting just about 3 miles per KWH, but apparently had a rather tough commute.

FYI, in Utah, it's 1.9 2 lbs C02/kwh. See here:
http://tonto.eia.doe.gov/ftproot/env...e-supdoc-u.pdf

So, by my calculation, electric miles in my PHEV Prius would actually raise C02 emissions (slightly) if I were charging off the Utah grid.

The plain old gas-powered Gen II Prius sets a pretty high standard of efficiency. You'll see a lot of literature on efficiency of EVs that uses (e.g.) the US average vehicle as the comparison. OK, compared to 21 MPG, yes, electric looks good. Compared to 46, in some areas (like Virginia) it's a modest improvement, in coal-intensive areas, it probably is no improvement at all, relative to driving a standard gas Prius.

When we bought the Hymotion kit, we were able to buy power from a wind farm. It was the last big step in a fairly intensive attempt to reduce carbon footprint. (And, truth be told, both my wife and I thought it would be just basically pretty cool.) But that clean power option has since ceased in Virginia, and we are back to charging it from VA Power's standard generating sources.

When all is said and done: At Utah's C02/KWH, it's not clear you are even coming ahead by substituting a Prius-sized EV for a Prius. At least, not if the performance of the current generation of PHEV Prii is a guide. And if you upsize it - get an electric SUV -- that just makes it that much worse. I'm pretty sure that the Cal Edison tests of the RAV4-EVs showed about 3 miles per KWH.

The upshot is that if you want to spend money to reduce your carbon footprint, you can get much better bang-for-the-buck elsewhere. At least if you charge off a grid that uses a lot of coal. And if you're in a really coal-intensive area, it's possible you're spending money to raise your carbon footprint.


Edit: I should have read Richard Schumachers' comment first. He got to the point in a lot fewer words than I used. I'd guess closer to 75% coal for C02 break-even but that's a quibble.