Costs of a PHEV system.

Here is a copy of my email that I sent to my PHEV group today.

"
Well guys I unfortunately have to post that my pack of 20 Best Battery EVP20's is DEAD! Each battery has bulging on each side. You can easily see the protrusions centered on each cell, of each battery. I have not pulled them yet and I will take some readings on them when I do. They are not leaking. I will take pictures of them to post online later.

My pack cost me $900 and I got 300 cycles out of it. (I was lucky because most people would only get 200 cycles.) That is a battery cost of $3.00 per cycle. I got between 15 EV miles per charge with new batteries, and 6 EV miles per charge at the end of its life. That is an average of 10.5 miles for each cycle. That means my battery cost was $3.00 for every 10.5 miles, or a "battery only cost" of "$.285714" per EV mile.

Then there was the electric cost of about 60 cents per charge. Texas rates for wind energy is "15 cents per Kwh." That works out to be an additional "$.057143" per EV mile. These two figures bring the sub total of "Cost per EV mile up to, "$.342857" per EV mile. That doesn't even include the cost of all the other components of the plug-in system.

In the standard unconverted Prius I get 50 miles per gallon. At $4.50 per gallon, that is just 9 cents per mile. Meaning the cost of operating my Plug-in conversion is 25 cents more per mile than a standard Prius. However, I still am happy to use less Foreign Oil, keep our air cleaner, and I still believe Plug-In cars are a great next step for our nation to pursue.

We have to get the cost of electric storage down...and I mean way down. I estimate that the cost of these batteries would have to come down to $103.50 for the entire pack to be equal to the cost of the fuel consumption it offsets in a standard Prius. At this time I do not think that lead acid batteries can stay alive long enough to offset their cost. I am now looking for alternatives to use in my next pack."

I think I gave it my all, and I hope others can use this base to figure out what the costs and returns are for a PHEV system.

If you do the math on "ANY" system you might be considering, I believe you will see it to be more financially expensive that just leaving the Prius as it is. However, what is the cost of using so much Foreign Oil, and what is the cost of Clean Air? For some like myself it is not about the money!

Let’s say you could get 80 miles per day at 100mpg, by charging twice a day every day, when you normally get 50mpg.
That is equal to 40 gas free miles per day. And now let’s say your pack will last, oh I don’t know, lets use about three years so that is 365 days X 3 Years X 40 Miles, or 43,800 gas free miles.
To travel 43,800 miles in a 50mpg Prius at $4.50 per gallon, that would cost $3,942. So you would have to consider if it is worth, “for you,†to get a PHEV pack that costs more than $3,942.

For me it is worth it!
However I can’t answer this question for you. You have to do the math for yourself.

 

I know of several others who have had to replace their packs. I think I'm the only one on Priuschat.com who has done it. You can check the Calcars.org website and they say 200 cycles.

Knowing that and using the average of 10.5 miles per cycle you can figure how many miles you can get out of a pack. I was lucky and my pack lasted longer than it should have. I had a lot of fun over the past two years playing with this technology. I loved the “gas free weekends” while still driving my family to the movies and restaurants. I am still a supporter of Plug-in cars and I will most likely build my own Lithium-Ion pack, even knowing that battery management of so many cells is a PITA.

The point is, if “we” want this technology to take off, so we can get off of foreign oil, people need to know what to expect. Otherwise, we will just have a load of people out there talking bad about Plug-in Hybrids. The truth is They Work. Now the next step is to bring down the cost.

A standard Prius cost about 9 cents per mile when gas is $4.50 per gallon and you get 50mpg. Using my 15 cents per Kwh of wind energy, to get one charge cycle of power. (60 cents to go 10.5 miles, a.k.a “5.7 cents per mile”) That only leaves 3.3 cents per mile for the rest of the system.

That does not leave a lot of room to make up the cost of the system.

Just like with solar panels making the car efficient first makes more sense. However, I am not too fond of giving my hard earned cash to buy gas that gets burned in my engine and thrown into the air for all of us to breathe.

 

Yes, Steve has built one, and the real problem with Li-ion is lack of a reliable BMS. We won't know how good a BMS system is until the pack finally fails. IF you make the Li-ion pack too small you will really shorten the packs life. If you make it too big, you have the problem of managing those extra batteries and up the cost of the pack. Since the Prius already gets a great gas mileage it is very hard to justify “ANY” PHEV conversion in terms monetary benefit.
In other words, you will buy less gas, but you will spend more over all doing so.
I just want people to understand that before they jump onboard thinking they are going to save money.

 

Dmckinstry,
Yes I have been using Clean Domestic Wind Energy and I would like to get PVs on the roof of my home. I rebuilt my PHEV kit to fit completely under the decking in the trunk, and there is no cutting at all to the fabric trim pieces in the trunk so you can't even tell the PHEV pack and charger are there. I priced it at $6,000 installed complete with heavy duty springs, but I have not had many takers because I insist on telling everyone that it costs more to operate a PHEV then it does just to operate the Prius as is. I still had a few takers though.

The charger puts out a lot of heat so I think i would recommend that someone who can, just keep their spare and leave the charger at home so it is always out side of the car and the pack stays cooler. That won't work for everyone so fans kick on when you plug-in the car.

Now if we could just get the price of energy storage down!

 

I am starting an open source group for an open source charger, an open source BMS, and an open source CAN spoofing board. I'm not sure where to begin but I know it needs to be done! This would be all not for profit.

Thank you aminorjourney! You get my point. Yes Plug-ins work but the cost is still to high to bring them mainstream. There are ways to bring the cost down.
1. A good charger for less than $1,000.00 U.S. Lets build one for about $200 in parts at home.
2. A good BMS for Li-ion/LiFo batteries. One that checks every cell for a minimum of parts that can be built at home. for $200.00 U.S. total.
3. The box problem has been solved as you can get one built at any metal shop for about $100.00. You'll have to add about $25 in when you get it home.
4. Can-view cost has to come down and the auto industry makes a CAN reader/tester = Spoofer for about $200.00. We could open source that and bring it down to around $50.00

I don't see any reason more open source work on PHEVs could not bring the cost down to $1,000.00 for everything except batteries. With group buys that could come down too.

Dave a PHEV conversion can be done now without the car being down. You can do it in a few weekends and still drive it. Many of the parts can be made by yourself so you can keep the cost down.

Please contact me if you think you can contribute to an open source project for the Charger, BMS, or the CAN Board. There is a lot of data on this on the web already but I just don't have the time to track it all down. The goal would be to keep all the costs for the converter down to a minimum so we can put more on the road. Lead-Acid is out so now we need to look to other alternatives. Yes a second Prius battery is a cheap way to go but we would need Mrbigh’s input on how far you can go with just one or two extra packs.