Plug in Hybrid conversion

[calpal]

What's the latest? Is the cost reasonable? Why isn't Toyota offering to do conversions on the Prius's out there? If they're expecting us all to turn in our used Prius's to get the new Prius's w conversions I think they're going to be mistaken.

[Bob64]

As with anything high-tech, the cost is never reasonable (unless your rich and willing to spend more then 1/4 to 2x the price of the car to upgrade it to a plugin).

The latest battery technology is expensive and unproven.

[ken1784]

Originally Posted by calpal

Why isn't Toyota offering to do conversions on the Prius's out there?

Are there any car makers who offered any conversions before?
AFAIK, I know none. Anyone?

Ken@Japan

[chogan2]

I got the Hymotion conversion, and I think that's still the least expensive turn-key conversion you can get. For an individual, that will cost about $11K with shipping and installation. (Fleet owners can get a significant price break off that.) Before the nosedive in the price of oil, Hymotion was selling them about as fast as they could make them. Don't know what the status is now.

From the standpoint of total cost, at $4/gallon for gas, it was marginal at best -- I'd have had to keep the car for something over 200,000 miles for the conversion to pay for itself. At $1/gallon (which I think we may see pretty soon now), it'll never make sense strictly from the standpoint of cost savings.

My family goes the extra step of buying wind-based electricity. (At least, that's the theory, what we actually do is mail a larger check to the electric company each month). So you can tell where we're coming from on this.

There are also a number of kits, but my reading on most of those is that the cheaper ones rely on lead batteries, which imho is a loser -- lower up-front cost but higher long-term cost due to the need for frequent battery replacement (not to mention recycling a few hundred pounds of lead every three years.)

The Hymotion batteries have been tested to 3,000 full discharge/recharge cycles without "failure" (meaning, continuing to hold at least 80% of original charge), which means they ought to last the typical life of the car. Although, of course, you won't know that as a fact for some time yet, and there are only few tens of them out there with >2 years on the road. But so far so good. Mine works as advertised -- we're getting low-90's gas mileage (though of course we are expending grid electricity to achieve that, and actual mileage is quite sensitive to how the car is driven, so not everyone could achieve that, and some are going to do much better than that.)

FWIW, A123 (the battery manufacturer for the Hymotion conversions) also sells to DeWalt Tool, so their battery packs are on the shelf now as a mainstream hardware-store product. So it's not really all that exotic any more.

The way I see it, durable lithium-ion batteries are popping up all over the place these days. Basically, they've now figured out a number of different chemical and physical configurations that yield long-lived and relatively inert lithium batteries. So you have a whole bunch of manufacturers who are getting in on the game. China's largest battery maker (BYD) bought itself a car maker so that it could sell EVs and PHEVs -- kind of a nice inversion of the pecking order. I'm not sure what the (near-term) plunge in the price of oil is going to do to all that ($34/bbl today and falling), but it's pretty clear for the longer term that the basic technology is abundant, and that the raw materials are not too expensive (e.g., no scarce or rare materials required). It'll just be a question of getting the average cost down through volume production.

On the downside, the fact that this is a retrofit introduces some limitations that are kind of a pain, and that I'm pretty sure Toyota could avoid when building a PHEV from scratch. I have an EV switch installed, so I can get in the car and drive it like an EV - the gas engine never starts. Nice for getting around town. But if you hit 34 MPH, the gas engine has to start. That's unfortunate when a lot of the streets around here are 35 MPH. I also get the impression (backed up by some studies from one of the US national labs) that the configuration of stock Prius software plus retrofit PHEV kit gives you less than optimal performance. Above 34 MPH, you end up spending a lot of the time using the engine at relatively low load, which tends to be inefficient. You'd think that if you integrated the systems better you could squeeze better performance out of it. Oh, and the other thing the national labs studies showed is that the car runs dirtier because the engine runs colder with the PHEV kit installed. Not a huge difference, and running dirtier than an extremely clean baseline, but it's another indicator that the retrofit approach is a little less than optimal.

But basically, no serious complaints here. Works as advertised.

[richard schumacher]

If you get your electricity from a coal-fired power plant a PHEV provides no net greenhouse gas reduction. And as chogan2 points out, at $11K (and even with $4 gas) it's very hard to get any payback of direct costs from a conversion.

[PeakOilGarage]

Even if your electricity is 100% coal as the source, it is 2x more efficient than using gasoline alone to power your vehicle.

[hill]

Originally Posted by PeakOilGarage

Even if your electricity is 100% coal as the source, it is 2x more efficient than using gasoline alone to power your vehicle.

Probably even higher efficiency that that. It's WAY easier to scrub one set of coal fired furnaces, than a 100,000 cars. Sheesh just do the math. That 'dirty coal' argument went out with the 1960's ... back before the high tech coal furnace scrubbers came in vogue. Plus, when you factor in all the hydroelectric, wind, solar, nuke generation, the equation gets much better.

[richard schumacher]

Yes, coal power plant exhaust can be thoroughly scrubbed of all pollutants, except CO2. That's the problem. Gasoline stores much of its energy in hydrogen, which becomes water. Coal is almost entirely carbon.

Back-of-envelope: driving a Prius 45 miles uses about one gallon of gasoline, which releases 9 kg of CO2. Driving a PHEV 45 miles on electricity alone might in a good case use 20 kW-hours of electricity, which, delivered from a coal-fired power plant and including transmission and conversion losses required about 10 kg of coal to produce and created about 20 kg of CO2.

If you/your electric utility gets most of your/its energy from something other than coal then an EV or PHEV could well cause a net reduction of greenhouse gasses. But don't assume that is so.

[Fibb222]

Originally Posted by richard schumacher

Yes, coal power plant exhaust can be thoroughly scrubbed of all pollutants, except CO2. That's the problem. Gasoline stores much of its energy in hydrogen, which becomes water. Coal is almost entirely carbon.

Back-of-envelope: driving a Prius 45 miles uses about one gallon of gasoline, which releases 9 kg of CO2. Driving a PHEV 45 miles on electricity alone might in a good case use 20 kW-hours of electricity, which, delivered from a coal-fired power plant and including transmission and conversion losses required about 10 kg of coal to produce and created about 20 kg of CO2.

If you/your electric utility gets most of your/its energy from something other than coal then an EV or PHEV could well cause a net reduction of greenhouse gasses. But don't assume that is so.

Assuming your guesses are roughly correct, what about the CO2 produced in the production of gasoline, not just the burning of it?

[Fibb222]

Originally Posted by chogan2

Mine works as advertised -- we're getting low-90's gas mileage (though of course we are expending grid electricity to achieve that, and actual mileage is quite sensitive to how the car is driven, so not everyone could achieve that, and some are going to do much better than that.)

Sorry to hear you're on ly in the 90s. I was hoping you'd keep it up over 110 mpg.