by Eric Richard

One of the big questions I’ve had over the recent years is whether plug-in hybrids are an important part of the solution to our problem or really just a placebo that makes us feel better without solving any of the problem.

As background, the idea behind a plug in hybrid is that you have a large battery array, much like a typical hybrid, but you recharge it by plugging your car into a conventional power outlet.  For example, you drive your car to work and home and then plug in the car over night to recharge its batteries.

The fundamental notion here is that the average American drives something like 40 miles per day. So, if you could get a car that could go at least 40 miles on a single charge of electricity, then you could make a huge dent in the gasoline usage of cars.

But here’s the big question — aren’t you just getting rid of one form of dirty energy (burning gasoline) for another (potentially burning coal at a power plant)?

Well, we no longer have to ponder this theoretical question.

The Electric Power Research Institute has teamed up with the National Defense Research Council to publish a report that studies this question.

There were a couple of interesting findings here for me.

The first one is probably the most important. According to a San Francisco Chronicle article about the study:

Researchers also found that plug-in hybrids reduced greenhouse gases no matter what energy source was used to produce the electricity, whether coal, nuclear, hydroelectric, wind or solar.

This is a very important finding since it answers the question about whether you are just moving the problem to a different location.  The basic answer is no, you are not just shifting the problem around.  You really are solving the problem.

One of the other findings of the report is probably obvious if you think about it, but still very interesting. According to Felix Kramer, founder of CalCars.org:

Scientist have confirmed that unlike gasoline cars, plug-ins will get cleaner as they get older — because our power grid is getting cleaner.

Let’s think about that for a moment because it is a very interesting point.

If I go out and buy a traditional gasoline powered car, it is going to have some emissions profile. And over time, that profile is very unlikely to get any better. In fact, as the car ages, it is likely to get slightly worse.

However, with a plug-in hybrid, you have a very interesting situation; since the electricity source for the car is coming from outside the car, the emissions profile can actually improve over time.

If the electricity coming to your house is “greener” over time, then your car’s emissions profile is going to actually improve over time.

It’s almost like you are doubling the benefits of moving to a greener power supply; not only is your home energy getting better, but you are also reducing emissions created by your car at the same time.

Maybe this just appeals to me as a “software guy”, but I think this is a fascinating benefit of plug-in hybrids since it no longer locks your emissions profile to a point in time.  Without any change to your car, you can actually improve the performance of your car over time.

On a somewhat related note, the San Francisco Chronicle article had a very interesting comparison of a Prius vs. GM’s concept car — the Chevy Volt.

The article says that:

Hybrid cars are essentially gasoline-powered vehicles. All the electricity they use comes ultimately from the gasoline engine. But the gas engine in a hybrid vehicle is smaller, and it is turned off when the vehicle is stopped or cruising at low speeds.

In contrast it says:

The Chevrolet Volt’s gasoline engine does not drive the wheels; it only charges the batteries. The electric motor powers the car at all speeds, and the Volt can travel 40 miles on batteries alone.

What it means is that the Prius is really a gas-powered car that happens to have an electric engine and battery to help assist it while the Volt is really an electric car that happens to have a gas engine to assist it.

This may seem like a bit of a semantic difference, but I don’t really think it is; it really is the next generation in the evolution of cars. The Prius hasn’t yet solved the problem of driving at full speed or for long distances on the electric engine alone. Solving this problem will be a big leap toward much cleaner cars.