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I have a question since a couple weeks about hybrids cars during their normalized cycles. I thought about it when I read that for the Enhanced Range EV (Volt...) the EPA is doing the EPA cycles in regenerative mode (if I understood correctly) and then indicate what is the pure EV range.

For the hybrids, the electricity in the batteries only comes from the ICE and so is derived from the gasoline.
In the case the batteries' level is the same at the end of the cycle than at the beginning then the consumption is the real one.
Sadly the batteries' level is certainly lower at the end than it was at the beginning which means that during the cycle the system consumed more energy than it regenerated and so the consumption is under-evaluated.

More and more constructors (Ferrari, Porsche, Peugeot...) are proposing big cars with big engines and small consumptions thanks to hybrids systems. I have the feeling that these consumptions are under-evaluated. Per example a Prius' consumption with an engineer kit on a normalized cycle should be better than a stock Prius.
To cheat the normalized cycles, you just have to conceive a big enough battery so the system doesn't have to be in regenerative mode during the tests. This also should explain why it's more difficult to match EPA ratings in an hybrid.

So I would like to know if the batteries' levels before and after the normalized cycles are public information.

What could be done for hybrids cars is to run 10 cycles and publish the first (cold engine and full batteries) and the last (hot engine and low batteries) ones.

Denis.

http://www.smidgeindustriesltd.com/leaf/EPA/EPA_test_procedure_for_EVs-PHEVs-1-13-2011.pdf, which refers to standard rules says the following of PHEV CS tests:

"The charge-sustaining test for PHEVs starts
with a discharged battery."

I haven't been able to find information about HEVs. It's possible they could set up the car so that it will use up the battery during the economy tests and end with low SoC.

Thanks a lot for that document. Great to see that the depleted battery test is done when the battery can be plugged-in and not only for EREV.

Now I would like to know what the Plug-in version of the Prius will get as EPA rating. It will certainly be lower than the Hybrid version. It will be fun to listen to the journalists' comments trying to explain that the plug-in system can't pay for itself :)

Denis.

Hi Denis:

Even the HEV has its initial and final SoC accounted for within its EPA test cycles and I am sure it is done on the ADR and NEDC as well.

The Prius PHEV-12/13 will probably arrive with a 47 to 48 mpg combined rating because the only real difference is that it has an extra 150 + pounds of battery. Do not quote me on that exact figure because I will have to look it up.

What I am more concerned with the Prius PHEV is the price. The pack is only 3X’s the size of the base NiMH and from an OEM cost perspective, should only have added about $2K to the price of the car. Rumors are still circulating that Toyota is going to try and pocket an extra $6K for it however?

Wayne

Cost of the product is one thing, the market cost is anyother thing.
How do you put a price on the research what was done on the Prius PHEV?

I think we will have wait until the true pricing is released before we get pissed off :D