Today's hybrid car runs on a mix of electric power provided by a large battery pack and by a gas engine powered by gasoline. A full hybrid will run at low speeds on all electric power, while the gas engine takes over at higher speeds. In order to recharge the battery pack, either the gas engine or regenerative braking pushes energy back into the storage. You can travel for a mile or three on all electric power, but the gas engine will turn on as the power drain on the battery pack is tremendous.
A plug-in hybrid is basically the same concept, except the battery pack is larger and can be recharged by plugging the car in. After the juice wears out, the gas engine takes over moving the car along and recharging the battery pack along with regenerative braking. You can go farther on all electric power, but movement of the car is provided by both the gas and the electric motor.
Extended Range Electric Vehicles (E-REV) are plug-in hybrids, but with a twist. The gas engine does not move the car. Instead, it is just there to recharge the battery pack which powers the electric motor which moves the car.
The electric motor, when powered by a fully charged (plugged in overnight) battery pack, can move the car on its own at whatever speed up to 40-50 miles. You can count on some re-charging from regenerative braking. But after that, the gas engine begins recharging the batteries until you can get back to a plug.
Basically, you have an electric car, whose range has been extended by the gas motor. Current estimates put the Chevy Volt, the most talked about E-REV on the way from GM, fuel economy somewhere between 120 and 200 mpg. Can you imagine a car that gets 150 mpg?
Pros of E-REVs
What are the benefits of E-REV over plug-in hybrids or just hybrid cars? To put it simply, you may not need to put gas in the car again. If your every day commute is short enough and you have access to a plug, you can always charge the battery pack via plug and never need to 'gas up' again. Plug-ins, since they are designed to run the electric and gas motor in tandem, will need to be re-fueled even if you do plug it in every night. If you're traveling greater distances, a plug-in can be more efficient, but for most people who drive less than 40 miles a day, the E-REV may be the better choice.
Most conservationists feel that running on electricity, rather than oil, is better for the environment. I'm not an expert in this area, but I believe it would be easier to regulate the electric companies than it is to regulate the cars. One source of power, compared to thousands of sources, is just simpler.
Another positive note is lessening the dependence our country has on oil. By running more on electric, rather than gas, we can cut our oil use drastically.
And, for now, electricity is cheaper as a fuel than gasoline is. Your location will vary depending on how much your electricity costs and when you plug-in (night time electricity can cost less than daytime), but there are some estimates that an all-electric car costs you 2-6 cents per mile to drive. The Prius, in comparision, costs 21 cents per mile to drive. The E-REV should end up having fuel costs closer to the bottom of that range.
Of course, there's the cool factor associated with being the first to drive a new type of car. The first to drive the Insight or Prius off the lot were certainly asked a lot of questions about how and why they were buying the first generation of modern hybrids. I'm sure the new owners of the E-REVs on the way will get the same kind of notice.
A bonus that may not appeal to many who are interested in the new technology is the performance levels. Based on hybrid car sales, it's the cars that focus in on fuel economy that are the winners. But, if applied, E-REV engines can be designed for performance levels instead. Take a look at what the Karma will be able to do and you can see how powerful these engines can be without even trying.
And then there's the federal government tax breaks on E-REV already in place. The Chevy Volt is already being estimated to qualify you for up to $7,500 in tax credits. That's if you qualify and so on and so forth, but that's a pretty nice discount on the sure to be expensive Volt.
And, while we haven't seen them yet, I'm sure the E-REVs coming out will qualify for local perks just like hybrid cars have. Better parking, access to HOV lanes, local and state tax breaks, etc... Just getting access to the HOV lane can be quite a relief depending on your commute.
Cons of E-REVs
But, of course, it's not all bright and cheery. When it comes to E-REV technology, there are just as many cons to consider as there are benefits.
For instance, do you even have access to a plug where you park your car? You probably don't have one at your workplace or wherever else you go, but what about at home? Do you live in an apt buiding and there's no extension cord long enough?
It may take 6-8 hours for you to fully re-charge the battery pack. Will you be able to do that consistently, or will you be relying on the gas engine to charge the batteries all the time? What if you forget to plug-in? There goes your fuel economy for the day (I've seen an estimate the Volt may have gotten a rating of 40+ mpg, so it's not like it would be a tragedy). There are some 'quick chargers' being developed and deployed, but I'm guessing it won't be something so cheap you'll want one in your garage.
Do you have to worry about the battery pack getting depleted if you leave the car parked for a week? a month? I'm not sure you could 'jump' these batteries easily.
And, of course, you probably will have to re-fuel with gas, too. Is that a nuisance factor, having to re-fuel twice? Plugging in at night (every night), and if your commute is long enough, having to re-fuel too?
And is electricity any cleaner than gas? There's certainly enough debate on the matter that I'm not weighing in on the matter, but from the reports I've seen, it all depends on where you live and how your electricity is produced. Yes, you will cut down on oil imports, but oil independence may not be your motivating factor. If pollution and 'green' products are your motivation, you may have to look closely at this one.
And, of course, there's the biggest CON of all; Cost. The Chevy Volt is estimated to cost somewhere in the range of $40,000. That sort of up-front payment is not feasible for a lot of people. Given the current economic climate, the number of people willing to pay that much for a car is probably going down right now. Everyone I've spoken to about the Volt, who has heard some things and is getting excited about it, has quickly cooled down when they heard that estimate. When you look at the Prius, which runs in the $20K range, and the new Insight, which will cost under $19K, some of those who are interested in the Volt may be turned off.
The look of the Volt (not E-REV) has also been a detractor so far. After seeing the concept vehicle, then seeing the production vehicle, a lot of people took their names off of the 'waiting list.' Designed for wind tunnels, the Volt came out looking a lot like the Prius and the new Insight. Mind you, the fuel economy benefits are plentiful, but if you're looking to distinguish yourself from the crowd, the new look doesn't do it.
How much will it cost you to repair the new vehicle whenever anything goes wrong? The battery pack may be the most expensive item in the car, so if something goes wrong there, ugghhh... That's not likely to occur, and I would also expect GM et. al. will continue the high warranty levels they have on their hybrids right now (including battery replacement cost), but that still leaves all the other things going on under the hood.
Any repairs on a new type of vehicle like this will most likely have to occur at the dealership. So, if you think you can save money by going to your local mechanic, think again. They may not even touch it for a routine oil change. So, even though oil changes and such will occur a lot less often, the overall repair and maintenance cost will most likely end up on the high side since you will have to rely on the dealership repair shops.
So, is an E-REV right for you? Not if you're making an economic decision it isn't. But, if you're interested in moving cars away from gasoline, cutting our oil dependence, interested in making yourself noticed, or hate going to fill your car up but don't want the limited range of an all electric vehicle holding you back, then an E-REV may be the car for you.
At least, if you have the money to buy one.
Friday, December 05, 2008