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A Better Place
August 20, 2008 8:33 PM   Subscribe

Shai Agassi's Audacious Plan to Put Electric Cars on the Road. Now it's Agassi's turn. He starts off uncharacteristically nervous, stammering a bit. He's got something different, he says. A new approach. He believes it just might be possible to get the entire world off oil. For good. Point by point, gaining speed as he goes, he shares for the first time in public the ideas that will change his future—and possibly the world's.

Shai Agassi plans to remake the automotive world with a new business model. Taking a cue from the way the mobile phone industry works, he wants to make electric cars cheap and even free, and then charge consumers for the electricity used, analogous to airtime charges. Batteries will be decoupled from the car and owned by his company and not the consumer.

All this attempts to solve the problem of electric cars taking too long to recharge and not being able to travel longer distances. With a large-scale infrastructure of charging stations, drivers can charge their vehicle just about anywhere, and when they need extra juice they can drive up to a battery changing station to get a fully charged battery in minimal time. Software will also be a big component of the system, carefully managing the car's use of electricity to make sure it gets replaced before it runs out.

So far he has two countries willing to beta-test for him, a lot of capital, a single car, but not much else to show for it.
posted by destrius (68 comments total) 10 users marked this as a favorite

 
I could see that working. Pull into the station, an automated system removes the discharged battery and installs a charged one. Away you go. The station never runs out of batteries: you have to give to get. So long as an adequate stock of charged batteries were on hand, it'd be slicker than teflon.
posted by five fresh fish at 8:58 PM on August 20, 2008


I read the Wired article on Agassi yesterday and was impressed. I mean, you hear about these clean-energy future pipe dreams from idealistic innovators all the time, but this guy has two large nations backing him up in a very tangible way (68% tax reduction on gas cars?).

I'm especially looking forward to how his plans will play out in Hawaii. From what I've seen traveling there last winter, they're hurting for energy, with the high costs of trans-Pacific shipping raising the prices of everything and forcing an assortment of mandatory conservation measures. In a way it struck me as a mini-oil crash confined to a single state. If Better Place can alleviate the pressure, it'll be a very good sign.

The only thing that bothers me is this:

The [Hawaii] governor's people wanted to know why this wasn't just shifting the environmental burden to the electric utility. Agassi said he'd pay a premium to buy energy made only from renewable sources, making it cost-effective for the utility to put in wind farms or solar-powered plants

I worry how much this premium will have an impact on his business model, and how that sacrifice would look to potential investors.

Still, the total annual cost estimate of fueling with gasoline compared to electric was pretty compelling. $3000 vs. $1050? Sign me up.
posted by Rhaomi at 9:03 PM on August 20, 2008


He believes it just might be possible to get the entire world off oil.

There's a misconception that some people have that oil refineries take in crude and produce gasoline for a while, then switch to producing diesel, then switch to producing jet fuel, then switch to producing lubricants, and that any given barrel of oil can be processed into anything the refinery wishes to.

That isn't the case. A refinery is a big fractional still. Petroleum contains all kinds of different sizes of hydrocarbons, and what the refinery does is to separate them out.

Which means that if you need diesel and jet fuel and lubrication oil, you're going to get a lot of gasoline too whether there's a market for it or not.

In fact, when in the 19th century people like Daimler began to experiment with internal combusion engines for vehicular use, one of the reasons they considered using gasoline as a fuel was because at the time it was a waste product of the petroleum industry, which was in the business of producing kerosene for lamps. The early petroleum industry developed because whale-oil had become too expensive and too scarce due to overhunting.

Refineries do use cracking towers to break some of the heavier fractions down into lighter components, so that they produce a larger percentage of gasoline and diesel and jet fuel than they otherwise would, but even if they didn't a lot of gasoline would be produced regardless. If there was no demand for it, they'd do with it what they did with it in the 19th century before Daimler et. al. came up with demand for the stuff: burn it off at the refinery in order to get rid of it.

Of course, that isn't what would really happen. What would really happen would be a classic demonstration of supply and demand. If demand fell, so would prices, and with lower prices demand would once again rise.

The point is that if you somehow dream of "getting the entire world off of oil" you have to come up with replacements for every fraction which is currently used. You can't do it just by reducing the demand for gasoline.

I saw an interesting number. I don't know if it's true, but it sounds about right. What it said was that if the entire US switched 100% to non-gas, non-diesel cars, American petroleum use would only drop by about 1/3. That's because there would still be plenty of demand for all the other fractions: jet fuel, diesel used by ships and locomotives, home heating oil, lubrication oil, waxes, and tars. (Also petroleum used as a feedstock for plastic and other chemical synthesis.)
posted by Class Goat at 9:05 PM on August 20, 2008 [49 favorites]


Er, that should be "assortment" link should point here. Clumsily malformed URLs get me every time...
posted by Rhaomi at 9:05 PM on August 20, 2008


cojones, indeed, but I like the idea. If the batteries used to run the cars are anything like my laptop batteries, they would be the most depreciating portion of an all electric car. I'm not sure how he's going to make money only on the battery replacement. I'm fairly certain that for this to work, you'd have to have a standard adapter that works across most makes and models of cars. The horseless carriage wouldn't have gotten off the ground if ford and cadillac required different fuels. All propane tanks fit all propane grills.

For an energy revolution to take place, you'll have to have a standard for passing that energy around, especially in the case of an electric car powered by hot swappable batteries.
posted by Freen at 9:12 PM on August 20, 2008


And require extensive amounts of complicated robotics at every single fueling place. And making fuel up of stranded cars rather difficult.

I have to wonder about the weight of the batteries. From what I could determine, contemporary hybrids have a weight of over 100 pounds. Any time a car ran out of power, due to bad judgment or a malfunctioning electrical system, it would require a tow truck, if only to have something like a cherry picker to lower the battery into place. Doable though.

The biggest concern I've always had for all electric cars doesn't seem to be addressed any better than anywhere else: how to build up all the infrastructure. Replacing batteries has never been a problem, just create one that can be easily replaced. Creating places that are always within a hundred mile limit will be the problem. Gas stations within a hundred mile limit even now almost everywhere, even on the long as East/West roads of the Midwest. But putting these everywhere would be something.

This doesn't even cover work vehicles that may never sit near a conveniently placed charging spot.

And it seems it is an all or nothing approach. No hybrids as of yet. It'd be great if he got together with Chevy to see if he could provide an adapter, or at least the ability, to convert the Volt to his system when it comes out.

Granted it looks like he'll need a great deal more buy in from all the auto makers in order for his system to work.
posted by zabuni at 9:28 PM on August 20, 2008


I appreciate this, but what has to change isn't the fuel. It's the automobile model itself.
posted by dhartung at 9:44 PM on August 20, 2008 [1 favorite]


His concept is pretty interesting, but something about it just makes me feel that it just isn't innovative enough; like he had a moment of insight but didn't follow it through fully and instead stuck on conventional approaches to the problem to come up with his solution. I can see how moving to a mobile phone like model will help deal with charging infrastructure issues; companies in the business will have an interest in providing "charging coverage" to larger areas in order to woo customers.

But the battery replacement thing might need a bit more thought. Like Freen mentioned there has to be some standardized system for replacing batteries; given how big and heavy batteries are I don't think a purely mechanical solution of lifting the battery out of the car via some robotic crane will cut it. That will put heavy limitations on how car manufacturers design their vehicles.

Also, I think his idea is most suited for solving the issue of daily transport within urban areas, i.e. people driving to work and back, or making short errands or trips within the city. However, there might be better solutions to the problem than electric cars, for example public transport, bicycles, some communal micro-vehicle system, etc. You really don't need a large vehicle that can fit 5 adults and 2 bags of luggage just to get to work. But of course, pushing to remove cars altogether will probably be an even more difficult task in many countries compared to his current endeavour.
posted by destrius at 9:56 PM on August 20, 2008


What about motorcycles? Somehow, an electric Harley just doesn't cut it.
posted by Class Goat at 10:14 PM on August 20, 2008


The biggest concern I've always had for all electric cars doesn't seem to be addressed any better than anywhere else: how to build up all the infrastructure.

Start with one city. If you put a few stations in one city, you can get many people in that city to switch. Then work on the next city, and make sure there are sufficient stations between those two cities. Incentive to switch in all participating cities grows with each city that joins the system. Eventually, someone will hammer the last spike between LA and NY.
posted by pracowity at 10:29 PM on August 20, 2008 [1 favorite]


If this succeeds I expect it to play out in the exact same way as it always does. For example Sony Honda comes out with a tape battery that's better than the more popular model. If not that then the standard varies from continent to continent. I'm not saying it won't work, but it would be nice if everyone worked together on this one instead of screwing over the consumer. Fingers are crossed.
posted by furtive at 10:36 PM on August 20, 2008


Start with one city. If you put a few stations in one city, you can get many people in that city to switch.

Yeah, but you won't break even for years. The only way you'll get anyone to switch initially is to sell below cost, and I mean everything: the cars, the fillups, all the maintenance.

This is not dissimilar to the problem the cell phone industry faced when it booted up. The business plans for most of the big carriers included a fundamental assumption that they'd suffer huge losses for at least ten years, possibly fifteen, as they built up infrastructure without having the customer base to fully pay for it all.

And that was for a product that only costs a couple of hundred dollars to buy.

The transition you're talking about is possible, but only with a mammoth investment -- or with a mammoth government subsidy. I'm not sure I believe that the private investment money exists to finance it, given that there are so many other, less risky things to invest in (like oil futures, heh), and I'm also not sure I believe that there exists the political will to spend the government money to do anything like this.
posted by Class Goat at 10:41 PM on August 20, 2008


This is a good idea. I could see it working more easily in more densely populated areas like the UK. Even better still would be to combine it with something like ZipCars so that there is no upfront cost to buying the cars at all, plus your customer base are already used to planning a bit more than us car-owners do.

I would assume that there would be a smaller, easily replaced battery to run the car in to the garage if you ran out of charge, something like a regular car battery size.
posted by fshgrl at 11:00 PM on August 20, 2008


Wow. Dennis Miller.
posted by From Bklyn at 11:07 PM on August 20, 2008


I would assume that there would be a smaller, easily replaced battery to run the car in to the garage if you ran out of charge, something like a regular car battery size.

A car battery weighs about 27 kg, give or take. Energy density is on the order of 110 kJ/kg. So it's just shy of 3 megajoules.

Regular gasoline is about 35 megajoules per liter. So a car battery has about the same amount of energy as 85 mL of gas. That's about 3 fluid ounces. How far do you think you'd get on 6 tablespoons of gas?
posted by Class Goat at 11:18 PM on August 20, 2008 [3 favorites]


The [Hawaii] governor's people wanted to know why this wasn't just shifting the environmental burden to the electric utility. Agassi said he'd pay a premium to buy energy made only from renewable sources, making it cost-effective for the utility to put in wind farms or solar-powered plants.

While we're mucking with numbers, let's try a different one. Ignoring Hawaii, let's talk about California. CA used 15.672 billion gallons of gas in 2007. 3.79 liters per gallon, 35 megajoules per liter, 31556736 seconds per year, and you do all the math and it turns out to be a 24-hour, 365.24 day average of 65.9 gigawatts.

That's the "alternative power" our hero will need to add to the electric power grid in order to offset all the increased demand for electricity, ignoring such things as losses in battery charging, transmission losses, or all those other pesky 2nd Law of Thermodynamics things. Since this is just a rough estimate, let's round up to about 100 gigawatts to cover all those inefficiencies which the laws of physics don't allow us to ignore. (When it comes to this kind of thing, 35% loss is actually doing extremely well; it would probably be even worse.)

Solar cells currently in broad daylight do really well to produce 100 watts per square meter (a 10% conversion rate at high noon for mass-produced solar cells; higher rates are possible but only by using esoteric materials which won't scale). Figure about 10 productive hours per day (and that's generous) then you're producing a 24-hour average of about 40 watts per square meter.

A million square meters per square kilometer, so to produce 100 gigawatts you need 100,000 square kilometers of solar cells. Turns out you'd have to pave more than 20% of the surface of California to do it. Ain't math fun?
posted by Class Goat at 11:47 PM on August 20, 2008 [2 favorites]


This transportation model makes a shitload of sense in Israel — it's a very small country, trips are pretty short, there's extra mandate to avoid fossil fuels, and nobody drives across the border — it might as well be an island. Nobody would care that they can't fill er'up in Egypt, Jordan, or Lebanon.

Would also work pretty well on actual islands, especially those with a relatively substantial population, and no regular continental ferry traffic.
posted by blasdelf at 11:49 PM on August 20, 2008


Rats, I botched my last math step. 100 gigawatts, 40 watts per square meter, a million square meters per square kilometer, you need 2500 square kilometers. (I left out the 40.)

Still an impressive area, though. Not trivial.
posted by Class Goat at 11:51 PM on August 20, 2008


You also left out that internal combustion engines are >%20 efficient at extracting those 35 megajoules per liter, and electric motors are <%80 efficient. Even accounting for losses in batteries (especially from non-ideal use), the electric car is going to be at least twice as efficient per megajoule.

When you take into account that electric cars don't have or need anywhere near the amount of horsepower that gas-guzzlers do, it adds up further.
posted by blasdelf at 12:04 AM on August 21, 2008 [1 favorite]


or with a mammoth government subsidy.

If a city government switches, you immediately have demand for the cars and citywide infrastructure. New York, for example, runs more than 10,000 small gasoline-burning vehicles (people carriers, not garbage or fire trucks). They plan to keep buying replacements for the gasoline-burning cars, making a large ongoing investment in the system that supports them. They could instead buy into a system that supports electric vehicles. You can call it a subsidy or an investment. Either way, the city spends money to get something better (cleaner local air, quieter and cooler local environment, less dependence on oil, etc.) in return. The city could also make it possible for employees to charge their own cars (or swap batteries) while they're at work; an eight-hour charging time is no big deal if it's while you're at your desk.

But a city government can also do a great deal at very little cost: reserve prime real estate (the best parking spaces) for a certain class of vehicle (small, short-range, low-speed, stop-and-start, zero-emission, cool, quiet) and allow only such vehicles to be used in certain areas. Declare the rules and let the best system win.
posted by pracowity at 12:17 AM on August 21, 2008


Well solar panels aren't the only source of renewable energy. I happen to know that a single bolt of lightning can produce 1.21 gigawatts of electricity.

Solar panels in the sunbelt, wind farms in the wind belt, highly efficient power transmission lines to deliver it. Either that or nuclear plants which is how I'd go if I was dictator.

Also the 65.9 gw of power created by gasoline is after those internal combustion engines have themselves overcome the 2nd law. So if you make the electric exactly as inefficient as combustion (and I have absolutely no idea if they are better or worse) then you are back down to 65.9 (all things being equal).
posted by Bonzai at 12:23 AM on August 21, 2008


You also left out that internal combustion engines are >%20 efficient at extracting those 35 megajoules per liter, and electric motors are

Um, you got your symbols backwards there...

When you take into account that electric cars don't have or need anywhere near the amount of horsepower that gas-guzzlers do

I would disagree with this. With electric engines, it's not that you need less power so much as the motor makes it's power where typical gasoline engines don't. With an electric motor 100% of it's rated torque is available at 0RPM, so you get a much zippier feel for normal city driving. (this is also why diesels, with their vast amounts of torque available much lower in the power band as well as maintaining significant torque over a broader range when compared to gasoline, are really taking hold. The Audi LMP diesel race cars reduced the number of gears to 5 because they had so much torque they didn't need any more gears)
posted by inparticularity at 12:30 AM on August 21, 2008


Is it a coincidence that the two countries that have signed up for beta-testing, Denmark and Israel, are so small that there really aren't any places you cannot go to on a 100 mile battery?
posted by sour cream at 12:38 AM on August 21, 2008


The whole world off oil? I'll settle for most of the world out of their damn cars.
posted by regicide is good for you at 12:40 AM on August 21, 2008


Why oh why does Hawaii not use geothermal power? On this map it looks like they don't even have one geothermal plant > 100MW. With all the volcanoes in the area surely it's a prime geothermal generating area?
posted by PenDevil at 2:07 AM on August 21, 2008


sour cream: And isn't Denmark already nearly oil (or at least foreign oil) independent?
posted by PenDevil at 2:08 AM on August 21, 2008


What do you do with the waste batteries?
posted by sfts2 at 3:02 AM on August 21, 2008


A similar system for buses, which makes sense because most bus fleets operate in one area, was run in London for quite a while before going under. There was an article in The Economist about it.
posted by sien at 3:04 AM on August 21, 2008


Turns out you'd have to pave more than 20% of the surface of California to do it.

You sound like you think that's an outrageous proposition, but it seems quite reasonable to me. The end of oil will mean big changes, and big changes in land use sounds lot better than many of the alternatives. We'd better get going, though. That's a lot of solar panels to install.
posted by mr. strange at 3:14 AM on August 21, 2008


I appreciate this, but what has to change isn't the fuel. It's the automobile model itself. - dhartung

I'll settle for most of the world out of their damn cars. - regicide is good for you

Class Goat also illustrates that things have got to change. Car use has to drop considerably and transport efficiency has to increase considerably. A happy side effect will be a drop in the number of people killed by automobiles (currently 1.2 million people per year).

The cost of motoring/oil use is not just the huge environmental impact (during all phases of it's life-cycle), it is also instability and war in many places in the world. This fighting over natural resources will either finish us, or be finished by us*.

*Does not apply if the bird flu gets us first.

I wonder how long it will be before the Koories in Australia will be able to get back to their normal lifestyles that have been interupted by the European invasion, and whether they retain enough knowledge to succeed at living on the land. They didn't use to have cars to get about, so they walked. Seemed to work for them for the 40-120,000 years they have been around for.
posted by asok at 3:55 AM on August 21, 2008


"Hey, man, your car is looking pretty beat up."
"Yeah, I want to get a new one, but I'm only seven years into a 10-year contract."
posted by Eideteker at 4:53 AM on August 21, 2008 [1 favorite]


OK glass goat. I stink at math. Help me out. Would 3 trillion dollars be a meaningful government subsidy........
posted by notreally at 5:29 AM on August 21, 2008


The whole problem to me seems to be the current non-scalability of 'green' energy sources. If we could produce clean power in large enough amounts, I would consider the whole system of distribution etc. for electric cars to be largely academic. I'm sure there's a bit more to it, but the whole energy thing seems like a far bigger hurdle.
posted by Edgewise at 6:16 AM on August 21, 2008


Shai Agassi's idea might work today in small countries or islands. Once batteries become more efficient and range is 300+ miles, than it's no different than gas and it could work in bigger countries.

The problems though are huge.

1. Competition. People want choice in cars, not just any car so long as it's Shai Agassi's car.
2. Infrastructure. Building out all these charging stations is massive. Not to mention battery swap stations. Agassi is taking a top-down AT&T monopoly style approach which would never work in many places.
3. Chicken and egg. No cars w/out infrastructure, no infrastructure w/out cars.

Perhaps these things can be overcome by rolling out on a small regional basis like the wireless networks did/are. However it is unclear what level of adoption is needed, what economy of scale is needed. The US can't "ban" gasoline cars, so it will take a technology that is clearly superior to get mass conversion.

Agassi's choice for a company name "Better World" is telling, an appeal to altruistic motivation, which suggests it would be a niche product among greens - is it better for me? That's what most people care about.
posted by stbalbach at 6:19 AM on August 21, 2008


It seems like his plan requires a monopoly on electricity in order to work. I mean, you give someone a car, what's to prevent them from 'filling up' with their home power connection every day before work, possibly using cheaper electricity from a coal burning plant?

Maybe his plan takes into account that people would take the convince of battery swapping over 'ordinary' charging, but still.

I wonder why there isn't more interest in hydrogen fed, internal combustion engines. Everyone seems to want to go with hydrogen fuel cells but hydrogen can power an ordinary ICE just fine. I think BMW sells a hydrogen powered 7 series and it seems like hydrogen could be added to our existing gas station infrastructure pretty easily.
posted by delmoi at 6:39 AM on August 21, 2008


Who do you call when you drive up and the batteries you want are all stuck in the machine? Do they have some bigger machine give the smaller machine a body check?

And this robotic power proboscis. Can they guarantee that I won't have nightmares about it?
posted by cowbellemoo at 7:14 AM on August 21, 2008


I wonder why there isn't more interest in hydrogen fed, internal combustion engines.

Lower efficiency and nitrogen oxides (particulate pollution), says the wikimind.
posted by cowbellemoo at 7:38 AM on August 21, 2008


He needed a network that allowed cars to tell the grid how much charge they were carrying and how much more they required. The system had to know where the car was so it could tell the driver where to go to "fill up."

So someone would have information on where every car on the road is at any given time? Or could one opt out of the network at a given time, counting on their own good senses to tend to battery recharge? If not, this would require coming pretty close to giving the government the surveillance society they want. Maybe since this is a green solution, when the feds start tapping into the network they can call their project Herbivore.
posted by kigpig at 7:46 AM on August 21, 2008


"Better Place" is a pretty cool name for a company - short, memorable and heavenly. Also, if it takes off, I bet it will rile these guys.
posted by rongorongo at 8:06 AM on August 21, 2008


I can see the benefit in having the cars be able to guide you to the nearest charging station while you still have enough charge to make it there, but I don't understand why the car needs to communicate to "the grid" how much charge it's carrying. If you don't need that feedback (which I don't see why you do), then you're just asking for a fancy GPS navigation system in the car, integrated with the electric equivalent of its gas gauge. That doesn't seem impractical.
posted by Kadin2048 at 8:17 AM on August 21, 2008


It seemed like part of the business model was that BP was going to charge drivers based on energy consumed, which would be tracked by the car's fancy computer. So you can plug in anywhere, but you'll pay more than the plain cost of the electricity. Basically you buy (or get for free) the car upfront, and you pay off the cost of the battery over time, as you use it. The analogy to mobile phone networks is key here.
posted by rusty at 9:31 AM on August 21, 2008


I wonder why there isn't more interest in hydrogen fed, internal combustion engines. Everyone seems to want to go with hydrogen fuel cells but hydrogen can power an ordinary ICE just fine

"The Hydrogen Hoax" article has been cited here before. It makes interesting reading if (like me) you had assumed that hydrogen was a pretty good future fuel choice.
posted by rongorongo at 11:09 AM on August 21, 2008


It's a cool idea, and he's addressed the battery issue (currently the biggest drawback of electric vehicles) head-on. Bravo. I don't 100% agree with the approach, but there's enough value to the idea, and apparent backing, that it will hopefully grow and change into something better.

To me, personal cars & trucks should be smaller. The Smart car (regardless of what some US reviewer said), and even the new small Hondas and Nissans show what's possible, and the smaller size makes electric power even more competitive.

Class Goat, how long have you been part of the oil lobby? You've overplayed some otherwise reasonable objections, all of which can be addressed.

Yes, the package that Better Place is selling is too optimistic and his goal of completely displacing oil is of course unrealistic, but it is nonetheless a great step. Certainly it's a better-thought-out approach than just farting out a few hybrids (Chev Tahoe hybrid... jeezuz) or waving cornstalks and shouting "Ethanol!".

Sidebar - y'know, this summer has been a clear indication to me of how easy it would be to make a substantial change in consumer habits. The spike in gas price was accompanied by a tracking decline in vehicle use. Hellooo, McFly? Could there be any more concrete proof that a higher gas price would alter North American driving habits? If part of that gas price increase was for a carbon tax or to fund some other significant efficiency program, what could we then achieve?

Yes I also know why we won't even try this, and instead we'll be late adopters of technology developed and adopted elsewhere, same as we let Europe and Japan own the market for small cars. And why is there a huge choice of diesel-equipped cars and light trucks in the world, especially Europe, but they're nearly non-existent in North America?

[/get offa my lawn, gaaah]
posted by Artful Codger at 11:49 AM on August 21, 2008


I love electric cars, and will buy one when they get a bit more affordable, but this scheme gives me the creeps.
This smells like the inkjet printer model, where the printer is cheap but the ink can only be bought from one supplier and costs more than champagne.
I really don't like the idea of DRM is on the charging connection - I don't want a situation where only one company has power points on the street that my car will talk to, which actually seems to be the business model here. I also don't want a system that prevents my employer from putting in free charging points at work, and I could easily imagine Better Place forbidding that in the license agreement. I don't want a system that prevents me from from fitting my car with strap on solar panels and going totally off the grid, and there is no way Better Place could allow that with this business model.
posted by w0mbat at 12:07 PM on August 21, 2008


Man, I wish MeFi let people edit their posts. I meant "I really don't like the idea of DRM on the charging connection".
posted by w0mbat at 12:10 PM on August 21, 2008


> I don't want a system that prevents me from from fitting my car with strap on solar panels

The only system preventing the above is physics. Ain't nowhere near enough surface area on a typical car to charge it in any realistic time frame. Unless you live in Arizona and drive just 10 miles every month.
posted by Artful Codger at 12:14 PM on August 21, 2008


ClassGoat, I trust you didn't know better when you wrote:

Solar cells currently in broad daylight do really well to produce 100 watts per square meter (a 10% conversion rate at high noon for mass-produced solar cells; higher rates are possible but only by using esoteric materials which won't scale). Figure about 10 productive hours per day (and that's generous) then you're producing a 24-hour average of about 40 watts per square meter.

17. What are Photovoltaic Peak Watts? The maximum rated output of a photovoltaic device, such as a solar cell or array, under standardized test conditions, usually 1000 watts per square meter (0.645 watts per square inch) of sunlight with other conditions, such as temperature specified. Typical rating conditions are 68°F (20°C), ambient air temperature, and 1 m/s (6.2 x 10-3 miles/sec.) wind speed.
posted by saulgoodman at 2:03 PM on August 21, 2008


hey saulgoodman, read your citation again...

The test INPUT CONDITIONS are 1000 watts per square meter of sunlight.

If that's the input, then given a conversion efficiency of 10%, then the expected optimum output of a photovoltiac panel would indeed be 100 watts per square meter.

Ta.
posted by Artful Codger at 5:01 PM on August 21, 2008


Recent efficiencies are heading north of 40%.
posted by five fresh fish at 6:12 PM on August 21, 2008


... but those are research results, and not yet in production. Hopefully soon, though.
posted by Artful Codger at 6:49 PM on August 21, 2008


not sure i understand why 1 square meter of sunlight =/= 1 square meter of PV panel? (not trying to be contrary, just need it explained to me.)
posted by saulgoodman at 7:20 PM on August 21, 2008


A photovoltaic panel converts energy from light into electrical energy.

sunlight = input
electricity = output

If the conversion efficiency of the solar panel is 10%, then

output = 0.1 x input

So if there's 1000 watts of sunlight energy beaming on our one square meter of photovoltaic panel, then you will only get

1000 watts x 0.1 = 100 watts of electrical power at the output.

I hope that's clear.

Also, if you go back to your source for that cite and look at #16, they state:

Modules using crystalline solar cells generate approximately 1 kilowatt of peak power for an area of 5 to 10 square metres. (... a bit more than 1 square metre)

( 1 kilowatt = 1000 watts)

The good news is that when panels with 40% conversion efficiency reach the market, then the same 1000 watts of sunlight should give us 400 watts of electrical energy.
posted by Artful Codger at 7:55 PM on August 21, 2008


Um, saulgoodman's numbers *are* output, Artful Codger.
posted by breath at 9:36 PM on August 21, 2008


Artful: duh. of course, that's right. sorry about that. the language in the source i cited confused me. i should have dug a little deeper (and looked for a better source). the wording: "the maximum rated output of a photovoltaic device, such as a solar cell or array, under standardized test conditions, usually 1000 watts per square meter..." threw me. Since sunlight peaks at only about 1000 watts/square inch, and PVs aren't nearly 100% efficient, of course the output can't be 1000 watts/square inch. sorry for slopping up the topic.
posted by saulgoodman at 9:44 PM on August 21, 2008


breath: yeah, that's what the cite says, as it's worded. but it's wrong. peak sunlight only contains (on average) about 1000 watts.
posted by saulgoodman at 9:45 PM on August 21, 2008


The Solar Constant is roughly 1400 W/m2. So, yeah, 40-50 W/m2 is a reasonable daily power average from a solar panel. Shouldn't rely on advertising copy, I guess. :-)
posted by breath at 9:49 PM on August 21, 2008


To bring the discussion back to the plan, though, I think this is definitely most likely to actually see the light of day of any of the green vehicle plans I've seen. Doesn't have any impossible technical problems (the battery replacement sounds no more complicated than a car wash), has a business plan, has a growth plan that supports incremental growth. Sounds awesome! Lemme know when there's a public offering.

Oh, and yes it's true that this is a bit of an "emissions-elsewhere" scheme, in that in implementing it, we should expect to see greater emissions from power plants. However, I don't think there's any alternative automotive powering strategy that isn't also emissions-elsewhere. Even ethanol. And there are certainly efforts to greenify power plants under way. Emission-free vehicles are just part of the solution.
posted by breath at 10:04 PM on August 21, 2008


Class Goat's original figures were still farcical. This claim:

A million square meters per square kilometer, so to produce 100 gigawatts you need 100,000 square kilometers of solar cells. Turns out you'd have to pave more than 20% of the surface of California to do it. Ain't math fun?

...is a particularly bad joke. Portugal has a modern photvoltaic plant partly on-line that will produce 88 gigawatts on 320 acres annually once its fully operational in 2010.

California's total area is something like 104,772,480 acres. I can't even begin to imagine a way to figure that 320 acres is 20% of that.

And there are plenty of other examples of solar plants that are as productive or more so. There's a practically antique mixed photovoltaic and solar thermal facility in the Mojave desert that annually produces 5 times as much power (354 MW capacity) as the one under development in Portugal.

Math sure is fun! If you pull it out of your ass.
posted by saulgoodman at 10:44 PM on August 21, 2008 [1 favorite]


(d'oh. sorry breath. should preview.)
posted by saulgoodman at 10:45 PM on August 21, 2008


The 100mile/160 km battery is a real sticking point in larger countries though. I live about an hour outside Toronto and if I keep driving away from it there are fewer and fewer gas stations because of the small population base. For several of my drives between rural towns there are no gas stations at all, if I am running low on gas I have to make a pretty big detour before I run out (and I drive a hyper fuel-efficient car). For instance, the drive between Sudbury and Timmins is one road, no gas stations and 150miles/240 km. It wouldn't make economic sense to build these battery stations close enough together to ensure a continuous journey without the population to support it. Anyone in an urban area like the Golden Horseshoe (population 10 million or so) would either never be able to go to a rural area (including cottages) or have to have a gas guzzling second car. I'd love an electric car and I think this is an awesome idea, just only for small countries unfortunately.
posted by saucysault at 11:01 PM on August 21, 2008


I think part of the problem is that in many countries land use has been shaped by car travel, like how in some parts of the US you must have a car to do anything in the suburbs. In some sense living too far away from your work and your daily necessities (the grocery, etc.) is not being energy-efficient, and should be changed.

Also for longer distance travel I could imagine some scheme that lets cars "hook up" to some power cable system like how electric buses do, so your car could travel for several hours on the interstate without needing to use its battery. Sort of like having a rail system but with individual cars being the carriages.
posted by destrius at 11:19 PM on August 21, 2008


I live about an hour outside Toronto and if I keep driving away from it there are fewer and fewer gas stations because of the small population base. [...] I think this is an awesome idea, just only for small countries unfortunately.

1. The ranges of the first gasoline-powered cars were quite a bit shorter than current ranges. Just as with gasoline-burning cars, electric cars will improve in range and other factors as competing manufacturers develop them. There is no need to reject the idea of electric cars because they currently don't quite meet all of everyone's desires from the beginning. It could be an "awesome idea" for most Canadians right now.
2. Just as with gas stations, and before that with inns that fed and sheltered horses, people who like to make money will build service stations for electric cars where there is demand for them. If all that's stopping electric cars from going from A to C is a lack of a service station at B, someone will quickly build a station at B.
3. There could be more than one type of vehicle on the road temporarily or permanently. I bet a lot of people out in the boonies still rode horses long after most city folk had switched to horseless trams, trains, buses, and cars.
4. Do you work in Toronto and live an hour outside it? If that's the case -- and it is the case for many people -- maybe you shouldn't live so far from where you need to go every day. (When "I live on the Moon and work on Earth" is used as an argument for keeping a Saturn V in the driveway, I have to suggest that you work out a better living arrangement and get rid of your dependence on giant rockets.) Electric cars already have the range for sensible commutes.
posted by pracowity at 1:27 AM on August 22, 2008 [1 favorite]


saucy, we live in west Toronto (20 min drive to downtown, 40 min bikeride, takes a friggin hour to go downtown by transit, but that's another rant for another time). You raise important points, but there are alot of workarounds.

First, it's clear that the electric car is mainly suited to limited-radius driving, or in dense corridors where there's lots of places to recharge, such as the golden horseshoe. For longer distances I can only hope that as driving continues to get more expensive, public transit will improve to the point where you can take a train to Huntsville, then rent a car (or get your scooter or e-bike from a locker at the train station, etc) and go the last few km to your cottage. The Zip Car idea is another possible solution.

Second, the gas-powered vehicle isn't going away very soon. It's entirely feasible that one could have a gas vehicle that's only used for weekends etc. In fact we do this already: we use transit mostly during the week, we have a Civic when we need a car, and we have a SUV that just gets used for errands or pulling our sailboat. It's still an improvement over daily driving - a car isn't polluting when it's just sitting in the driveway - and vehicles last longer too.

I'll try anything that reduces the total amount of driving done, or improves the efficiency and carbon footprint of the driving we continue to do. If we could reduce gas consumption by a third or even a quarter, we will make a huge difference.
posted by Artful Codger at 6:23 AM on August 22, 2008


The 100mile/160 km battery is a real sticking point in larger countries though. I live about an hour outside Toronto and if I keep driving away from it there are fewer and fewer gas stations because of the small population base.

(A) There is only one country larger than Canada. Almost all the other countries are much smaller and much higher-density.

(B) Even within Canada, almost all the population lives in a narrow, high-density band with plenty of gas stations within easy range of a 150km car.

(C) These cars aren't being pitched as a solution to travelling in the outbacks of Canada and Russia.

(D) Your personal need for an outback car is not representative of the vast, vast majority of people. Again, almost everyone in the first world lives within walking distance, let alone driving distance, of a gas station.

The exception is not the rule.
posted by five fresh fish at 7:17 AM on August 22, 2008


pracowity:
1. The ranges of the first gasoline-powered cars were quite a bit shorter than current ranges.

True, I am looking forward to longer ranges, that would certainly make my concerns mute. I don't want to wait decades though! I wonder how fast the range will be expanded? (not snarking, honestly curious)

2. Just as with gas stations, and before that with inns that fed and sheltered horses, people who like to make money will build service stations for electric cars where there is demand for them.
But that is what I was saying! Canada (and few other large countries) have weird population clusters with open spaces between them. So in the urban area they have enough population to support battery changing stations but as I said, in the rural area where I live I have to be careful not to run out of gas between gas stations. If there isn't the population to support gas stations now then I would be surprised if battery changing stations were more numerous. I would imagine the roads with the only changing station within 80 miles would get congested though as people altered their direct routes to instead hit a station. That would be a pain (I hate traffic). I wonder if there would be a rural/urban schism where the urban population could not go outside the city because of the lack of charging stations and the rural population could not drive near urban areas because of the lack of gas stations?

3. There could be more than one type of vehicle on the road temporarily or permanently.
Yes, but in my case, my family has limited ourselves to one (small) car. Given a choice, I would rather have an electric car but if there is no way to recharge my battery and it doesn't have to range to allow me to drive outside urban areas I use would be limited to the gas car. I see a lot of people choosing the Smart car for their second car but not their only car because of its limitations. Personally, I am planning on keeping my car for 10 years (then passing it to one of my children), this would mean a slow changeover which would then limited the demand for the stations. I may not buy an electric car for twenty or more years. The more people that choose electric the better, no?

4.Do you work in Toronto and live an hour outside it?.
Uh, no. I live in a walkable community on purpose. : ) However, I have family and friends who have chosen different walkable communities as well as amazing parks and conservation areas I like to visit frequently. Public Transit travels between urban areas but the population cannot support public transportation in rural areas. So I do like having a car.
posted by saucysault at 7:23 AM on August 22, 2008


(shoulda previewed)
fff:There is only one country larger than Canada. Almost all the other countries are much smaller and much higher-density.
I know, dammit, Russia is so screwed up at this point why don't they disolve into a bunch of smaller countries so we can be the biggest at something (besides shooting our mouths off)? Doesn't the US have a bunch of "fly-over" states with people spread out thinly though? The US is only slightly smaller than Canada. The urban/rural schism is interesting to me.

Again, almost everyone in the first world lives within walking distance, let alone driving distance, of a gas station.
I'm a walker, everything is walking distance. I could walk to you if I wanted. I just don't want to walk to the nearest charging station lugging a dead battery (there is no cell phone coverage where I usually drive, so no tow trucks). To begin with I didn't think there would be as many charging stations are there are gas stations now; in rural areas there are not as many gas stations as urbanites expect, so I would think there would be less charging stations. That would slow adoption of ALL-electric cars (hybrids would work fine but Agassi doesn't want that).

The exception is not the rule.
I never said it was. The demographics of metafilter skew heavily urban/suburban though and I'm just pointing out a different point of view. I LIKE electric cars, I WANT them to be practical for everyone. If no one in a rural area will buy them and some people in an urban area that need access to rural areas not serviced by train or bus won't buy them because there are no charging stations on their route then that is going to affect adoption rates.
posted by saucysault at 8:20 AM on August 22, 2008


While I'm not a fan of the cell phone model myself, I think this guy's ideas could really get the electric car market running quickly. Hopefully, the system will allow for partial participation, or competitors will offer varying levels. For example, I wouldn't mind buying the car, but I would prefer not to own the battery, and I'd like to be able to take part in the battery-swapping system. I would prefer not to pay a tarrif on electricity while the car charges at my home, however.

But not everyone is willing or able to put significant money down on a car that relies on an immature infrastructure, and the cheap/free car paid for by battery-charging fees would make a lot of sense for them.
posted by trebonius at 8:52 AM on August 22, 2008


Would multiple, smaller batteries accessed serially help address the problem of swapping batteries and/or needing a quick fix (running out of juice and being stranded, leaving the car unused too long, etc.)?

I could see folks a lot more willing to risk toting batteries weighing <25 lbs. or so, and if size were standardized, it'd be a dead simple matter to manufacture and market something similar to a small luggage cart that'd be stowed with the spare tire. Also, smaller standardized batteries, it seems to me, would allow for greater flexibility wrt vehicle capacity and performance. Small commuter car? 3-5 batteries. Larger family car or longer distance capacity? Up to 10 batteries, possibly distributed both fore and aft for better weight balance. I'm no EE, so maybe there's some reason this couldn't possibly work, but it makes sense to me in theory.

Also, with the recent gains in photovoltaic technology, wouldn't a roof panel as standard equipment on these vehicles just make sense, sort of as a "reserve tank" just to get you to the next charging/swapping station?
posted by notashroom at 10:33 AM on August 22, 2008


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