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A bit more about BEVs


Over the last week, I test drove three of the BEV's currently on the market. First, I drove BMW's new model i3. I'm going to assume my readers know about BMW. You can think of this as a $45K, give or take a few thousand dollars, depending on what state you live in and what options you order it with. It is an all electric drive car, which means no internal combustion motor ever drives the wheels of this vehicle. You can _get_ an optional ICE (internal combustion engine) and accompanying (tiny) gas tank. Here in the US, that is not under the operator's control regarding when it runs -- it kicks in when the charge gets low and recharges the battery, which continues to drive the wheels. Without Rex (the range extender), the i3 will go 70 or 80 miles, more or less like the Leaf and some of the other BEVs out on the market. With the range extender, you'll be pulling up to a gas station every additional 70 miles. I think.

Useful words: ICE, internal combustion engine, which is basically almost every car engine you've ever thought about until fairly recently, unless you are super nerdy. If you are super nerdy, I love you extra special more, just for that. BEV = Battery electric vehicle, which is what the i3 is, even tho it has that optional engine. Other types of vehicles include PHEV (plug in hybrid electric vehicle) and HEV (hybrid electric vehicle). You know about Prius -- that's a hybrid. There are hybrids (including some Prius) that you can recharge overnight by plugging them into the wall, and which if you don't drive very many miles a day, you can pretty much avoid every using the gasoline engine. A hybrid vehicle in general has _two_ power sources (the battery and the ICE) and a complicated drive system.

The second car I test drove was the Tesla Model S, which is a new American car manufacturer in California founded by Elon Musk, of PayPal and SpaceX fame, in addition to Tesla Motors. The cars are built in a factory in Fremont, CA, which is the same Fremont, CA factory described in such detail in one of the most popular This American Life episodes ever; listen to the podcast some time. It is absolutely worth it.

Here's the transcript: http://www.thisamericanlife.org/radio-archives/episode/403/transcript

I have mixed feelings about Musk, but I expected to love the Tesla. It has much more range than any other BEV out there currently, and Musk/Tesla Motors is putting a lot of effort into building out an extensive fast charging network to support the vehicles.

I will now digress about charging. There are three quick charging systems out there in the wild:

(1) CHAdeMO, which is what Nissan's Leaf (the third car I test drove) uses.
(2) Tesla's SuperCharger (self-explanatory)
(3) SAE, which is what BMW uses

These systems are _not_ intercompatible. You cannot charge a Leaf at a Tesla station and vice versa. In general, you can charge your car at a dealer that sells your car (all Nissan dealerships seem to have fast chargers, type of thing). You can also use sites such as this one:

http://www.plugshare.com/

to find stores that have chargers. However, while you can find some sort of charger in a lot of places, often it is not a fast charger. It's closer to your home charging experience, and a full charge could take 3 or more hours. The quick charging systems located above can generally charge 80% in about a half hour (they're all impressed with themselves if they can get it down to 20 minutes -- I don't see a huge difference there, but whatev).

Needless to say, this is not like driving up to the Self Serve, swiping your car, letting money drain out of your account for a few minutes as the black gold drips into your tank, and driving away, safe in the comfort that you can drive 200-400 miles before having to do that again. The difference in refill time (hours -- or, in a best case scenario, a half hour -- vs. minutes) combined with the difference in distance before you hit E (75 or so miles, unless in the Tesla in which case 200+, vs. 200-400 in a typical ICE) creates "range anxiety": am I gonna make it to where I am going?

While ICE vehicles experience relatively minor degradation in performance (range, etc.) in cold weather, batteries suffer in the cold. Experience in this area is still being developed, but expecting a 10% or more reduction in range during cold weather seems reasonable -- it's not even particularly conservative. Unlike ICE vehicles, the faster you go in an electric drive, the faster you drain the battery/the shorter your range. Because the car doesn't really know how many hills you will be driving up, much less how fast, it can really only guess how much further the charge in your battery is going to take you. Driving a BEV requires some careful consideration and rewards detailed route knowledge and repeat trips.

If your life is relatively predictable (you tend to go to the same places within the same area) and you live in a densely developed area, the range of a BEV might look just fine to you. And the cost to replenish the charge in the batteries at typical electrical utility prices might look _really really awesome_ to you. Recharging at normal electrical rates is going to typically come in under $10. Well under $10. Not too many people have ICE vehicles they can fill the tank for that price, altho, to be fair, it's not quite such a screaming deal when you figure it mile-to-mile. But it's still really good. When a BEVs power consumption is translated into mpg, it usually is 100 mpg or better -- you'd have to ride a low-power motorcycle or scooter to get comparable mpg with an ICE. I drive a Honda Fit, but that's a lot better than my Fit gets, which is more than I can say when comparing the Fit to, say, a Prius. Of course, you could accomplish a lot of the same goals with a plug in hybrid, but the batteries on that have even shorter range, so trying to get all of your driving in electric mode can be difficult.

The next obvious question is, well, how about charging at home, or some other place that I can control? You typically get a cord with a plug at the end with these cars for "occasional use" that you can basically plug in anywhere. It will take a long time -- 7 hours or more -- to fully charge your car that way, but overnight should be just fine. You can set up a circuit that is more or less like a dryer circuit that will shrink that down to 3ish hours. The Tesla can be bought with an option that will give you _two_ cords, so you can charge it twice as fast, and each of those can be the fast kind of charge. There are some additional options as well, unique to each manufacturer (as near as I can tell, anyway). But you can't do any better than the 80% charge in 20-30 minutes than I mentioned above.

Executive summary for those whose eyes glazed over: every electric car out there can be recharged anywhere there is an electrical outlet, if you are prepared to wait long enough. If you want to charge your car most of the way, quickly, there are 3 incompatible charging standards, one for Tesla, one used by BMW, and one used by Nissan Leaf. The Nissan Leaf standard is the most widely deployed, altho that may or may not be true a few years from now. You don't _have_ to install anything special at home to charge your electric car, but odds on, you will want to. You can probably do most trips in a BEV -- but having a good plan in place for trips that will tax your BEV's range is important to reduce range anxiety ("Am I gonna make it?") and avoid buyer's remorse. That could be a second car in your household ("I'll borrow my spouse's minivan"), rental or a carshare membership, or purchasing BMW's Add On Mobility option (which is a sort of amortized rental system -- I may post about that if I can find someone to supply a meaningful level of detail).

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( 2 comments — Leave a comment )
jinasphinx
Aug. 3rd, 2014 08:50 pm (UTC)
Sorry to hear the Tesla was so disappointing. Although it's always nice when you're trying to make a decision and there's a clear winner.

I see a lot of Leafs around town here, driving or else charging (at the movie theater & the hospital I used to volunteer at).
walkitout
Aug. 3rd, 2014 11:44 pm (UTC)
nice to know you are seeing them!
Roland doesn't see very many; I've seen slightly more. I get the impression they are perhaps a bit more common in Seattle, perhaps because the climate/battery concerns are reduced there vs. here.

It is nice there is a clear winner.
( 2 comments — Leave a comment )