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One of the best questions ever asked was about the feasibility of these cars. (i.e. are they actually viable, or are they engineers toys?)

I would pretty much have to respond that these are still very much just testbeds for solar research. Several square yards of solar cells (usually very fragile) are never going to be mainstream, and these vehicles are built to be as absolutely light as possible.
That said, these vehicles are amazing. I could easily push our vehicle with only my pinky, and total energy consumption at top speed was less than a hair drier. In my experience, these competitions really distinguish the brilliant and intuitive engineers from the commonplace ones.

All cars must pass several exhaustive safety checks, "scrutineering", where literally every bolt, nut, wire and square inch of composite is inspected by experienced engineers. (They even check the manufacturer's marks on bolts!) As a matter of fact, I remember that Texas A&M was disqualified because their vehicle rode an inch and a quarter too low to the ground. I wouldn't want to put one of our cars up against a semi, but safety is a primary concern to those involved. I mean, c'mon, how many people drive around much smaller (and less protected) motorcycles?

The 200w/sq. m is based on monocrystalline silicon PV. This is the cheapest but also almost the least efficient PV solution because the actual absorption is in the indirect bandgap energy of silicon.

There are thin-film PV solutions with much higher efficiencies (and much higher costs, and much higher toxicity involved in production). But there is also research going on on other semiconductor materials the hold out promise of high efficiency at fairly low cost. (I don't think we'll ever make thin films where there aren't some danged scary chemicals involved.)

Even so, your point is well made. Insolation is such that even if you could acheive 100% PV efficiency, you would still only have about 2kW/sq. meter.

Any realistic ground-based fuel production will require large arrays of PV. You'll need a lot of area to power your car.

But there are plenty of people powering their homes entirely off PV (entirely is a bit of stretch -- they use Propane or other combustion for a lot, including, often, for refrigeration).

People also have entirely solar charged electric cars, but again, they require a fairly large of field of PV panels. The real advantage here is that the efficiency of hydrogen as the energy storage is much greater than the efficiency of chemical batteries.

And, oh yeah, there are 100% solar powered cars right now that run on what they generate at the moment. But these are the cars in the American Solar Challenge which are a long way from practical household commuter cars.

But we have barely begun to put resources and research and capital into energy alternatives. I have always said that it wouldn't begin until oil prices went way up. I'm not even sure that we'll a lot of progress now. But I'm quite confident that the stability and price of oil will not steadily increase anymore. We're already seeing wind power become a fairly significant energy source. PV will follow. I think it will become common for homes to have grid-intertied solar power systems.

Alternative fuel cars are coming. Hybrids are just a first step. I don't know which technology will catch on, fuel cells or hydrogen combustion, but I'd bet we'll see petrochemical powered vehicles in the minority in my lifetime.
(I'm in my late 30's).

For most people, if they didn't insist on driving huge SUVs, current electric technology would be more than sufficient.

There are frequent brownouts in many urban areas during the summer because people are running their air conditioners. It's less frequent where I am, but it still happens. If the existing system can't fully satisfy peak demands, then switching everyone to electric cars is only going to make the problem worse - even "off-peak" charging, since off-peak will then become peak as millions of people plug their cars in to juice up. Lots of infastructure upgrades will be required to make it work...

Economies of scale. In the 80's an ICE was only about 20% efficient. I'm sure that has increased with on-board computers and fuel injection, but since most of the inefficiencies were from heat loss, I doubt that it has increased dramatically.

It hasn't :) And while it generally pays to "build bigger" (large powerplants having much better efficiencies) and electric motors nowadays are approaching 90%+ efficiency, battery storage systems are still extremely inefficient. By the time you get from the fuel to the road I'm not sure if you're spending the energy any wiser.

Doing some googling on the subject:

Coal powerplant: 45%
Transmission lines: 92% overall
Battery Charging: 87%**
Battery Discharging: 33%**
Electric motor: 98%

* It says "thermal" efficiency, but I'll take it as overall fuel->electric efficiency
** For lead-acid batrery. Depends on battery construction, charge and condition.

Multiply that up and you get an overall fuel->road efficiency of just under 12%. Ouch... if you have any other sources of information please share.

I'm going to have to agree with others here, there is no one alternative to fossil fuels. Electric, whether with fuel cell or battery technology is one of them. Biodiesel and Ethanol is another. They address different market segments.

Yes, exactly. My feeling is, though, that trying to replace petrolium fuels as directly as possible will be more sucessful than trying to replace/augment the existing infastructure. The "system" works pretty well and if it can be used it wold be worth it.
=Smdige=

Here's some links:

Our team - Sunsetters
American Solar Challenge - ASC
Formula Sun - formula sun
The other teams - teams

Ooh, I can't remember if there is a common website for the event. Search google for "college solar race" and it'll at least turn up a bunch of team pages.

There is also Formula Sun which runs car and bike solar races. Both of which are coming right up this month.

~~Guildencrantz

Oh, then you mean this:

Sunrayce 99

It doesn't say it outright on that page, but that rayce had solid clouds and rain 8 out of 9 days.

The leader finished with 56:10:46, while this year's leader finished with 51:47:39. However, looking at the overall top 10, it appears that the 2001 field was slightly better than the top 10 of this year's field. I'd say it means that solar technology is advancing but at a somewhat slow pace. Until we hit that breakthrough that gets the solar efficiency past 40%, we won't see much of any daily applications of this tech.

Then again, it's just my opinion, I could be wrong.

-Cyc

Bro, here's the schedule.

Can't help mentioning that I submitted a story Saturday (in time to see the cars on display) but it didn't get accepted by the editors. IT did have a link to the schedule too...

Solar Car Race - Chicago to California

We all know that solar power is cool. Even cooler is when you use it to go 80mph on a freeway, with the power consumption of a hairdryer! The American Solar Challenge unites teams from many Universities in the goal of racing their custom-built solar-cars from Chicago to California.
That's 2300 miles along Route 66! They start Sunday morning in Chicago, but you can check out the official schedule to see when the cars will be passing through your state. If you're in Chicago now, the cars are on public display (while last-minute tuning continues) at the Museum of Science and Industry.

Google has a number of related items. For photos and blogs, try these: ASC daily photos, ASC dialy diaries, a Stanford blog.

For the first time this year, 2-person cars will be entering the race. Unfortunately, only two of these passed the scrutineering tests: The Stanford Team is racing a 2-person back-to-back configuration. Here's a list of races held in the U.S.A. in the 90's. A similar race in Australia is less student-oriented.

[ I submitted the following as a story on Saturday. Plenty of links and info, but it got passed up. ]

Solar Car Race - Chicago to California

We all know that solar power is cool. Even cooler is when you use it to go 80mph on a freeway, with the power consumption of a hairdryer! The American Solar Challenge unites teams from many Universities in the goal of racing their custom-built solar-cars from Chicago to California.
That's 2300 miles along Route 66! They start Sunday morning in Chicago, but you can check out the official schedule to see when the cars will be passing through your state. If you're in Chicago now, the cars are on public display (while last-minute tuning continues) at the Museum of Science and Industry.

Google has a number of related items. For photos and blogs, try these: ASC daily photos, ASC dialy diaries, a Stanford blog.

For the first time this year, 2-person cars will be entering the race. Unfortunately, only two of these passed the scrutineering tests: The Stanford Team is racing a 2-person back-to-back configuration. Here's a list of races held in the U.S.A. in the 90's. A similar race in Australia is less student-oriented.

At "Sunrayce 99" (ASC used to be called Sunrayce) there was severe rain on 8 out of 10 race days. I was there. Average speed for the race dropped to about 20mph. From D.C. to Orlando, FL it was one wet mess.
List of prior races.

That's rough.

Seth

I am a part of my university's solar car program, but, unfortunately, we couldn't get our body made in time for the rayce. I did, however, make the 10 hour drive to see the cars in Chicago. If anyone is near where 'scrutineering' is in 2 years, they should definetely go see it.

I helped out with getting various information on different teams' cars, and some of the prices for the things are a bit ridiculous. My university's car is costing less than $150,000, which I thought was pricey until some teams told me that their cars cost 1.5 Million (Queens) or 875,000 (Waterloo).

I think most people think that the rayce is about showing people that we could have cars that run off of solar power, but that is entirely the wrong idea. The cars are made to show solar powers' abilities... if it can power a car, maybe it could do other things too (who woulda thought?)

I wish I could've gone on the rayce, but seeing all the cars was cool enough. I just hope our car makes it in time for Formula Sun next year! (Formula Sun Grand Prix is a track race every year)

http://www.formulasun.org

I am on the University of Virginia solar car team, and I remember some of these teams from the American Solar Challenge this summer. I have a few comments on the teams:

Arizona University:

If memory serves, these are the guys whose car spun out during qualifiers and flew through the air, tearing off the suspension when it landed. When I saw it happen, I thought they were finished. They had it up and running for the race and did quite well, much better than we did.

Futura:

I see they've withdrawn. They had some problems during the ASC. I can't really say what, but they were very far back in the pack despite what should have been a very high-performing solar array.

Kansas State University:

It's sad to see these guys are out of it, because we worked with them during the ASC getting our car and their car to pass scrutineering.

Queens University:

Wow. That car is nice. That's all I can say.

South Bank University:

These guys did pretty well in the ASC. They had an accident during the race and severely damaged their body, but duct tape kept them going and competitive.

University of Michigan:

They rebuilt their car 17 days before the ASC because it was destroyed during testing. They have a GaAs solar array, Lithium Ion or Lithium Polymer batteries, a very sleek design, and 4-wheel steering. Apparently when they redid the 4-wheel steering, they replaced the mechanical linkage with an electronic control. It's the most advanced solar car I've ever seen.

University of Missouri-Rolla:

These guys nearly won the ASC despite only having a 14% efficient array. For reference, some teams had up to 26% efficient arrays. Their car is incredibly light and efficient. Nobody in the race was even close to them on mechanical efficiency.

University of Toronto:

Good car. Nothing much comes to mind. Didn't see them much because they stayed ahead of us.

University of Waterloo:

Yet another very good car. They did a very good job of integrating the wheel farings with the body to keep aerodynamic drag very low.

That's about all I have to say about that. If you want to see how the ASC went, check out their website at http://www.formulasun.org/asc/.

Umm... Right. The "US competition" would be the American Solar Challenge, which I see you didn't participate in. Are you talking about the Winston Solar Challenge? That's just a low-level High School competition. I've been to it before (I won't say with who). It's neat, fun, and you learn a lot from it. Just don't go around thinking you "won the US competition", because you didn't, and saying that is just asking for trouble. You won a US competition, and should be proud of it. I know my team (from a different year) sucked. Your team has better funding and more members. Your car was better. I liked you guys. Just don't pretend you're better than you really are.

Your source seems to have missed the first column of the finishing times for the first place entry.

Chicago to California is a decent road trip

On another note

On sunny days, and on flat stretches of highway, the cars hit speeds as high as 110 kilometres an hour.

which is starting to be respectable.

It's already been done to an extent. SolarHost offers web hosting powered by solar power. They are the people providing hosting for The Formula Sun website. (Formula Sun, incidentally, is a group of races across the USA in various solar powered vehicles. Shameless Plug)

As with any technology, one of the best ways to move it along at a rapid clip is to pit talented people against each other in competition! Case in point:

Formula Sun

Fun stuff!

Mike