Friday, May 05, 2006

Electric vehicles are economically viable -- right now

One of the magic incantations you will find the less intellectually equipped chant whenever you're presenting something they don't like is the notion that something is "not economically viable". It's as if they expect the concept in question to go away if only they can pretend that it isn't "economically viable". Try it: pick something you don't like and start telling people "immigration laws are not economically viable" or "the death penalty is not economically viable" or "chocolate ice cream is not economically viable". See how easy it is?

1) Up-front costs.

The item in question is an old Toyota Corolla (1988), lovingly converted into an electric vehicle by a couple guys with too much time on their hands. The batteries are twenty old 12V batteries form an old emergency power generator starter from a hospital. The electric motor was purchased at McMaster. Most of the control-electronics were hand-soldered (It isn't really as hard as it first looks like, but in hindsight the investment of a couple hundred extra bucks could have saved a lot of time).

Obviously it is kinda difficult to put a price tag on something a bunch of home mechanics worked on for an extended period of time. Assuming all-new parts and a group of well-practiced converters, I suppose the whole thing could be done for $5-6k, probably more like $10k is someone actually wants to make a living at it.

Of course there's a lot of leftover pieces now - including a whole engine. In reality an electric vehicle is vastly simpler than a gas-engine -- no fuel injection, no valves, no cylinders, no fuel tanks or lines. So if a car was built from the ground up to be electric, it would probably be *cheaper* to produce than a car that runs on gasoline: fewer parts, simpler assembly. It would also last longer, as there's many, many fewer parts that can possibly break or get misaligned or any such things that happen to cars.

Economic viability: looking good so far.

2) Fuel costs.

Now our batteries were free - they were simply discarded starter batteries. This means that they aren't exactly representative of the performance that one might get from a brand new set of gel-cells and they probably won't last particularly long (since starter batteries are made to deliver a lot of power for a short time, while we're using them to deliver moderate power for quite a while). But hey, they were free.

If the car is hooked to the main for charging, it draws about 1000W (it is designed not to draw more) and we can get the batteries filled after about 8 hours. With fully charged batteries, the car has a range of just a little under 25 miles. Let me call it 24miles for round numbers.

This means that we're going 24 miles with 8kWh of input which just comes to three miles per kWh. Around here, the kWh costs about 7.5c, but let me round that up to 10c/kWh to be conservative.

3 miles for ten cents makes 30 miles per dollar.

This means if your car gets 30 miles to the gallon, electric is economically viable if you're paying more than $1 per gallon of gas. You do the math.

The reason this can be this way in the first place is because electric power (like just about everything else in the world) can be produced much more cheaply (i.e. efficiently) if you produce it in large quantities. Even if our power plants ran 100% on oil, the electric output would still be an order of magnitude cheaper than if we were to produce electricity from the same oil in a hundred million little energy-converters. Not only are we harvesting economy of scale, but we're eliminating a large number of processing steps to refine oil into the extremely clean gasoline that cars require and we're circumventing a hundred million gas station attendants to parcel out the fuel into gallon sized packets.

And not only can centralized production be much cheaper, it is also several orders of magnitude cleaner: since all the emissions happen at one place (ideally carefully chosen to be away from people and other animals) there's only one set of filters, one set of catalytic converters, one overall equipment infrastructure, which can thus be much better, much better maintained and much better controlled.

Now imagine this equation with a set of state-of-the-art batteries. Imagine the increase one could get out of regenerative breaks alone. Or out of an engine that was actually designed to be used this way, instead of an electric motor hooked to some random old car chassis...

3) Future proofing.

In reality, of course, only 2% of the US electricity comes from oil in the first place.

10% come from hydro power.

There are 77000 dams of some kind in the US, and less than 3% have some kind of hydro-electric generator attached to them. These 3% produce about 10% of the total US electricity consumption. Outfitting 50% of the already existing dams in the US (no new valleys to flood etc) with hydro-generators could cover the entire US electricity budget right there. Yes, hydro power generators do cost maintenance, there's silting to contend with, there's things that break and people who have to be around and run things. But they certainly do not incur any more upkeep and maintenance costs than oil or coal fired plants. And they produce no emissions while running without any fuel costs.

No fuel costs. All we'd need is a couple hundred (what the heck, call it an even 1000) hydro-generators attached to already existing dams and we could replace the total contributions of oil into the US electric grid with hydro power.

But of course once we're talking future, who knows what we're going to use to generate electricity tomorrow. Since electric power plants do not have to carry their fuel around (contrary to cars) they can truly and honestly produce power in the most economically viable way available at any time. Who knows what will be the cheapest way to generate electricity in 20 years. But whatever it is: the electric car will already use it. What does it cost to outfit a hundred million vehicles with a "Mr. Fusion"? The battery-car doesn't need one, because it'll run on fusion power as soon as it becomes available.

Economic viability: looking better by the minute.

4) Economic independence.

This section is a little trickier: what is the value of independence? What kind of investment is still "economically viable" if it gives you the knowledge of future freedom?

The question is about PV of course: photovoltaics. Once you have a battery-operated car, you can elect to put a couple solar panels on your roof and generate your mobility-juice by yourself from here on in.

Solar panels cost money. There are places in the world where they may or may not pay off, ever. On the other hand, some of the most heavily trafficked areas in the US (Like LA or Atlanta or Huston) have way more sunshine than you could shake a stick at: if I covered only the south-facing part of only my garage-roof, I'd be talking about 2kW of peak power (this is in AZ). That is 2kWh every single hour at peak production – and let's say half as much during most of the daytime hours. Since I only need 8kWh per day, this would give me a decent safety margin right there.

And if I merely use that electricity to power my car and never attempt to feed it into the grid or power my household equipment with it, I won't have to mess with inverters or even with a "certified electrician" to hook up my stuff at some exorbitant price. The price of the system would go in the direction of just the cells alone.

I'd need a second set of batteries and the setup would have to be more modular than it is right now: I'd want to come home in the evening, slide out the half-empty batteries, slide in the ones that have been charging all day, hook up the used ones to the charger for tomorrow and I'll be set to go.

Of course the roof and hood of this Toyota have enough area to put another ~300W peak capacity on there. Let's say I get 50% of that on average during daylight hours, say 12 hours (all of these are very conservative here in AZ), that would be 1.8kWh per day of just sitting there. Imagine a car that runs out of fuel on Friday so you just let it sit wherever it ran out over the weekend and for every day of sitting you collect 5 miles worth of fuel. What's that gonna be worth when oil runs out - or even just short. Or even just expensive?

5) Range

My commute is about 7.5 miles, so I have enough range to spare for the occasional detour to the store. As of now, I haven't really used the car for my normal commute and I won't for a while until we have fully clarified the whole street-legal situation. But I wanted to market this kind of system, what kind of range would be necessary to be useful? Obviously very few people will buy a car that can go 25 miles - but how about 50? 100? 200? Is there a "pain threshold" below which such a vehicle would be unmarketable?

Quite frankly I doubt it: people haven't exactly been expressing a lot of concern for range with gasoline-driven cars. If todays cars had half the range they have people would just refill their gas tanks twice as often. Which means there'd be a couple more gas stations. And people would fiercely defend their right to have a 90 mile range and resist any efforts to increase the gasoline efficiency of their cars -- just as they have been resisting the same thing in the past.

The last year I checked (2003) the Ford model with the best gas mileage got 36mpg. The original model-T got 37mpg. Meanwhile, it would be completely unproblematic to get twice that mileage: it would come at the cost of not having 200 horsepowers. One might have to make do with driving the speed limit. Such utterly reasonable things as gentle acceleration and appropriate speed alone would do wonders for the average mileage even without actually changing any technology. But does anybody out there really want to claim that all the technological progress of the last 100 years was unable to raise gas mileage by even a single lousy mile?

A car with a range of 100 or 150 miles will be just as suitable as a car that has a range of 200 or 300 miles for just about any task. Yes, for a cross-country trip, you may have to pull over a couple more times. Five or six times a day instead of twice or three times. But it is not as if the one number is any more problematic than the other one. Slide your battery tray out, slide in a freshly charged one. The highways are already dotted with gas stations every 50 miles. What difference would it make if they handled electrical cars?

6) So why isn't all this in place?

There's a lot of advantages here and at most slight inconveniences as a drawback. Why aren't we all driving electricals at least for our second cars as commute vehicles? Why isn't there a huge market for this? Why isn't this already all over the place? The obvious answer is left as an exercise to the reader.

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