Friday, May 18, 2012

An Electric Future

When I attend public meetings on transportation, I frequently hear that the future is in "electric vehicles". The underlying idea is that we can just keep up with the same road building, because in the future, there will be just as many cars as today - they'll just be electric.

So I'd like to do some thinking out loud about what an "electric future" might look like. I think it's easiest to start with the "final picture" - say, 50 years from now - and then to imagine a path from here to there.

So, the first and probably most surprising thing to realize is that an electric future will have fewer cars than today. I think there is absolutely no doubt about this. Why can I say this with such confidence?

Well, it has to do with energy constraints. As I discussed here, in BC we used 156PJ ("peta joules") of energy hauling ourselves and our stuff around by fossil fuels in 2008 - likely more today, 3 years later. Even taking into consideration a 3-fold gain in efficiency for electric engines, we do not make enough electricity to run all these vehicles. Not by a long shot. We'd need 4 site C dams, 4000 windmills (NB: a very, very large windfarm has 200 windmills!!!), 2 nuclear plants, or 4 coal or natgas thermal plants. Or some combination of these. Just to convert today's infrastructure to electricity - let alone accomodate growth. So clearly, just to provide the fuel for all these vehicles, we'd have to take some pretty ugly decisions. I'm just not convinced that this future will arrive.

An electric future will also require a complete rebuild of our fuelling infrastructure. A "battery exchange" type of station such as Better Place is pioneering costs about $300,000. A "fast charging" station is only 1/10th of this, but you can't have many such chargers too close together or you'll bring down the grid. Seems to me that any roll-out of charging infrastructure is going to be very expensive both for the grid (which will be payed for by taxpayers) and the station owners. It will likely require lots of government intervention, because of the "chicken-and-egg" thing - without a solid customer base of electric cars, which fuelling station owner is going to risk a $300,000 investment?

Electric cars are expensive. They require fossil fuels to construct (mining, casting, fiberglass, electronics...all require lots of oil) and as the price of oil goes up, so will the costs of the cars. Some of the components depend on exotic materials (specifically the batteries and electronics) that are unlikely to come down in price as they are limited commodities. At the moment, most electric cars are sold at a discount, and in some regions even subsidized by various levels of government. This is not sustainable if everyone's driving them. So, I'm not at all sure that electric cars are going to get any cheaper very soon.

Finally, battery-powered vehicles have limited ranges, currently not more than 150km or so. Maybe this will change as battery technology improves, but for the next 20 years or so it cannot. For this reason, long-distance freight movement is best done using electric rail, where no batteries are required (power is brought to the engine using overhead wires). Long-distance battery-based holiday driving isn't viable.

So, if you want an electric future, it's pretty clear what you should not be investing in, and that is in more road space for vehicles. Far better to provide mobility for all those folks who currently drive on fossil fuels, but in future cannot. Far better to be investing in public transportation and electric freight movement.

No comments:

Post a Comment