Electric-solar hybrid

If you mean mounting solar panels onto a car, then no, it is a very bad idea. All current solar power technologies use more energy to manufacture them than they will produce over their lives. Mounting standard heavy silicon panels to a vehicle is just plain crazy.

I am still waiting for the radical new developments that will one day make electric solar cells a viable green energy source.

The energy needed to manufacture a solar panel is purchased by the solar panel company. This amout of energy is thus represented by an amount of money included in the cost price of the solar panel. The solar panel company can live from its sales. Thus the cost price is less than the sales price which is the price you will pay as the end user.

Solar panels can be amortized in about 5 years time today (depending from technology) and their life is much longer than that.

Conclusion : A solar panel produces more energy than is needed to manufacture it.

Please stop telling the opposite to the world. This is a myth I have heard many times but was true a long time ago only when efficiency of solar panels was very low and when they had very thick layers of material, in other words, during the start of the development of solar panel technology.

For your information : the trend is towards ever shorter break even periods, because of solar panel technology becoming ever more performant per cost to produce and because of increased market price of electricity.

For your information : The latest developments based on quantum dots to make photovoltaic cells would have a break even period of a few months only according to one of the people I spoke with within a french company working on this.

Kind regards from a sunny Paris, France

Additionally, solar cells are currently being developed from modified plastics, and should be in production in a few years for use.

I'd love to see the analysis that shows solar panels pay for themselves in five years! I don't use $30,000 in electricity over a five year period.

If that were the case, everyone would be putting them on their roofs. That's total pie-in-the-sky hogwash.

Certainly, I'd love to re-roof my house with solar tiles and turn my electric meter in reverse. But the truth is, we're not there yet. Even in sunny California, the payback on the installation is still projected to be 20-25 years.

Ahhh, no. What I am talking about is taking ALL factors into account when calculating energy used verses energy gained. You cannot use a manufacturing cost vs sales price as it is not an accurate indicator at all (especially when government subsidies are included). The picture gets much worse when you have to take into account the converter and batteries. I have been following solar power development for many years and although there have been a lot of changes, they have all still been relatively small. Your standard silicon PV panel is only a few percent more efficient, and still requires vast energy resources to produce (don't forget you have to mine the silicon, then process it). Try running the figures yourself if you don't believe me.

But I do agree with you about quantum dots, they do look a very promising direction for sustainable solar power generation.

Just curious. If we use your argument, a car engine also uses more energy to produce than to use. If we factor in the mining for the iron, aluminum, copper, sand (for the glass), etc.

I'm also doubtful about the "solar panels use more energy to manufacture than they provide" argument. If that were true, it would have died as an industry a long time ago.

Granted that converting my house to solar power will not result in a five year ROI (more like ten actually) but that's savings none-the-less. I could certainly use the extra 1,200 pesos (about $27) per month that I can save.

Seems like some of the smartest people on this board are the most closed minded! - http://www.treehugger.com/files/2006/08/nanosolar_print.php

Just because a persons point of view differs from yours does not make them closed minded.

It does say that they percieve things differely than you. All of the points in this thread are of some value and cause folks to think about the issue under discussion.

Nanosolar's product looks interesting but they do not indicate anywhere the conversion efficiency or output power. There are plenty of thin-film solar cell products like this being developed (I know because I am very interested in using them for technology and products I am developing and so am following the new developments very closely), but the technology is still too new and the conversion efficiency too low (even with the reduced manufacturing costs they just aren't viable yet). As for the energy payback figures, well they mean as much as PMPO does when explaining audio power (ie- anything the marketing division wants).

Despite the huge cost savings of these panels, when they come to market they will be just under the cost of todays typical solar panel. All the cost savings will go into the pockets of the producers. Thye have the patent and until that runs out they will maintain the high prices for their own benefit. Not to mention that the cost to produce each panel may be low, but when you amortize in the cost to build those large production facilities (the largest in the world), the savings will be marginal

I think its unfair to add "the power it takes to produce the solar panels" into the equation. What about the power Ford or GM uses to produce their ICE's. Maybe you'll argue that the panels are a source of fuel and the ICE's are not. What about the power it takes to run a oil refinery factory? What about the energy it takes to get the oil from wherever the world it is coming from to the refinery then to the gas station by your house?

Digging earth deeper to get oil also takes tons of energy , this is perhaps major factor contributing to oil price rise , some day solar (power generating) panels will be as cheap as any other plastics , we are just getting aware of energy conservations ,utilisation now . sun has powered earth since billions of years and it will power on , civilised humans have long way to go to tap the incridible energy from sun

All variables must be taken into account when trying to build an accurate picture. This goes for both petrol, coal, solar, and all the rest. You cannot just ignore it out of convenience.

As for the energy that it takes to get oil out of the ground and process it, that too is also taken into account. Don't forget that you also have to take into account the infrastructure necessary to support it too.

Are you serious? I hate to think where we will all be in a couple of generations if that's this view is typical.

It's no longer entirely about 'me' or 'my pocket' as an individual.

In principal, I think you are right, except that it is fair to consider the energy that goes into making solar panels, just as we should consider the energy that goes into making all the stuff that goes into a car. Most car companies give at least lip service to the total life cycle costs of what they produce, with Volvo perhaps being the only one who has taken this seriously for very long -- and, of course, even they sell luxurious powerful and heavy cars which are not, as a group, any better than the products offered by several other manufacturers. Honda leads, with Toyota just behind.

Also, the often heard statement that "it takes more energy to make a solar panel than you will ever get out of it" is a myth that applies only to very old solar cells. Details are in this DOE report.

I believe thay have thin-film flexible solar panels, and they would not be heavy at all. Won't they work if wrapped around the vehicle?

Unfortunately, this is not yet an option, for two reasons: 1. The efficiency of the solar cells is too low, typically 10 - 12%. 2. Insolation (the energy from the sun per square meter) is too low. That figure is about 250 watts square meter, averaged out over the day, and 250 watts is about 1/400 the power of the engine in a small car (which is typically about 100 kW). So, even if solar cells were 100% efficient, they couldn't provide anything close to enough power.

On the other hand, if you build a large solar array, (much too large to mount on a car) and use that to collect energy over an entire day, storing it in batteries, then a micro car (800 lbs or so) can be powered (i.e. recharged) from less than $10,000 worth of solar cells.

You can't get enough power from a solar cell to generate meaningful amounts of electricity for practical use.

The real rate limit is battery technology. The cost and weight are the fundamental issue with EVs. The cost to charge them on a home grid is very cheap, but storing power is the hurdle.

That being said, there are competitions on the college level to build and race solar powered cars. You would not want to drive one as a daily driver, but it looks like a fun competition to design, build, and race!

http://archives.cnn.com/2001/TECH/science/07/16/solar.cars/index.html

Does anyone recall a race across Australia (presumably someone from that part of the world will), perhaps 15 years ago or so, for solar powered vehicles? Darwin to Adelaide I think. It might have been a project supported by Honda that won it (or was it GM??) with a really good average speed, maybe 65-70mph from memory. Suppose I should look it up instead of being vague.

Anyway, it gives an idea of the kind of weather you need allied to a very compact (in interior space) vehicleweighing about as much as a packet of cornflakes to run at useful speeds - admittedly without any 'normal' power plant.

I was hoping my employers were going to take an interest at the time. Darn.

OK it was 1987 (EEeek, 20years ago!) and it's become an annual fixutre by the look of it.

http://www.speedace.info/solar_racing_events/panasonic_world_solar_challenge.htm

If you could be interested in something a little smaller and closer to home, you might check out "electra-thon America.

That wasn't electra-thon with a 'g', could get us censored?

I'm an electric vehicle sceptic at heart but liked the idea of designing for efficiency both interms of mass and energy. I'm even more sceptical after reading on here that photo-voltaic cells are using more energy to produce than they generate. I'm staggered by that; can it be true? What are the figures?

Duh! Sorry, that was me forgetting to log in again.

As Randolph Toom pointed out, they idea that solar panels currently consume more power in fabrication than they can produce over their lifetimes is NOT TRUE.

I have seen his number of about 5 years +/- a year of use to break even in various places (but was too lazy to find a reference right now). That is quickly going down.

The reason they take so much energy to produce, are heavy, and are expensive is the use of silicon. Once that is replaced by another technology, there could be an exponential increase in viability for lots of applications.

One of the coolest technologies being developed is polymer based photovoltaics (http://www.konarka.com/). If that pans out the way they claim, some very interesting things could come about.

Photovoltaic Cells are vastly improving in efficiency and becoming lighter. This just improves viability. Of course all the research in the US is really done at an academic level. However, when they reach a high enough efficiency at a cheaper cost, industry may become interested enough to begin retooling and redesigning (or go bankrupt and hope the govenrment bails them out when they lose to Toyota/Honda).

There is a decent movie called "Race the Sun" (1996), based on the exploits of a US (Hawaii) High School team that builds a solar car to compete in the state Solar Challenge race then takes the car to Australia for the 1990 World Solar Challenge. Filmed in Adelaide and other Australian locations, as well as Hawaii (and probably California of course, doubling for other locations in typical Hollywood style!), the film stars Halle Berry and James Belushi as the teachers, but the real stars are an ensemble cast of kids headed by Casey Affleck (Ben Affleck's younger, smarter brother!), and a nice, and very funny, cameo by Steve Zahn, as an antagonistic, Germanic techno-nazi competitor in the WSC.

Supposedly based on a true story, but, well, you know Hollywood.....

Some liberties were taken with the engineering and science to make a better story, I do believe.

I have heard from a few people of a car that is in design in Japan being made up of graphite but will also be solar powered. This would provide strength, no tiles would need to be mounted to the vehicle as it absorbs energy through the body and it would be a lot lighter. I have looked on the internet but can't seem to find any information on this. Does anyone have any info on it?

This is the article that prompted me to post this thread. Perhaps this is what you heard of - http://www.gizmag.com/go/6256/

Although it seems to fall way short of practical, its a start. Dont know why the seats are not covered! Actually a little bit bigger cabin (and covered of course) and this could be a great car. Electric is definetly the way to go! I hope Tesla is a huge success, and when they build the luxury sedan for about 45k, ill be the first in line!

There are a couple motor scooters that hobbyists have built that are solar powered. One has fold out panels, and the owner rides it to work, opens the panels, and it recharges during the course of the day.

It would be a fairly reasonable proposition to power a vehicle the size of the Aptera or my own (much better!!)* vehicle with stationary solar panels. I agree with others that the payback can be as little as 5 years in some locations. Being that the car would no doubt be away from home when the sun is shining, you'd charge a battery bank with the solar panels, and then charge your car from the batteries. (You could also swap batteries, but this would be more complicated than just plugging in.) From battery pack to battery pack, charge rates can be very high, with some batteries being rechargeable in 15 minutes. (An ordinary home AC system does not have the amperage availability to do a really fast charge.)

I'd guess that the Aptera might be available in less than a year; my own should be available in a little over a year, and there are several other cars (micro and some larger) that should be coming out not long after that. All will have 100 mpg+ capability. Most will be competitors in the Automotive X Prize .

*

Blink, is that a picture of your prototype? You always mention your project but never give out any info! I would love to see what you got cookin in your garage!

Yes, that is the proof-of-concept prototype. In this pic, it is powered by a motor scooter power package, to enable general chassis dynamics to be tested before installing the hybrid powertrain. With the hybrid powertrain installed, I'll be able to do a lot of the testing I might otherwise do on a second prototype, but with lower risk and out-of-pocket expense.

The second prototype will use the same basic systems and control algorithms but will have two electric drive motors instead of one, two seats instead of one, and will be more "finished" instead of looking like it was stuck together with bubble gum. The basic production vehicle will be gasoline/electric hybrid, with diesel, plug-in, and full electric options. (It will be quite modular.) For all the technologies involved, we will lean strongly toward the tried-and-true: there are loads of opportunities for gaining a couple percent in efficiency by using very slick new components, but the cost sky-rockets.

The intent is to be able to price this at near $10,000, where 1. you don't feel as if you are making a financial sacrifice to drive a green vehicle, and 2. you could buy it as a third car, or as a primary vehicle for a college student, young single, childless couple, etc.

The time is certainly right for vehicles like mine. People are painfully aware of the societal, environmental, and financial costs of using oil -- probably more so than at any time in history. Even in the gas crisis days of the 70's, the issue was only financial, with a little inconvenience thrown in. Nevertheless, selling a vehicle like mine, in volume, will require serious marketing: we already have lots of efficient vehicles, but people still buy gas guzzlers as if there was no tomorrow (keep it up, and there may be no tomorrow!).

After I've nailed down a few intellectual property issues, I can provide a few more details as things develop.

A little power from Sun.

A good charger from AC 120 - 240 V + the efficient battery + electric DC motor/generator + the simplest biofuel powered engine seems to be an optimal solution for a vehicle of 2020s.

Also remove complicated mechanical power transmission - --> replace it by four or three- individual drives + wheels to improve stability and safety of driving and control + automatic protection to the reasonable level. We have already v. good industrial kind electronic gearing, we do not need gears in a transmisions box!.

Also remove complicated mechanical power transmission - --> replace it by four or three- individual drives + wheels to improve stability and safety of driving and control

What planet do you live on? Try selling that idea to the millions of drivers on our roads who use their vehicles for more than just commuting. The car (or truck) has become an extension of ourselves, for better or worse. Sure there are those who will buy into your ultra-green vehicle. For them it is probably a political statement. If they live in an urban environment, usually transport no more than 1-3 people or pets (no more than two being adult humans), have a relatively short commute, and never travel long distances, it is in fact an elegant solution.

For others, who live in another world, a world where sometimes you have to haul a lot of stuff, or even a lot of people, (soccer Moms, baseball Dads, or vice versa) or want to take the whole family (4-6 adults and big kids) to visit Granny up in Michigan, and cannot afford plane or train tickets, or whose plant shut down forcing them to take a similar skilled job nearly 100 miles away or else they end up working for minimum wage at Wal-mart. Maybe for others it is just vanity or thrills; they want the biggest truck, the fastest sports car, and they can afford the purchase price, insurance cost, and fuel costs.

The "complicated mechanical power transmission" is necessary to harness and control the output of the powerful engines needed (or desired) in today's more powerful vehicles. Besides which, automotive technology is also advancing where, in some cases, the mechanical power transmission is actually getting less complicated, e.g. advances in continuously variable transmissions, for one thing. Electronic control has also simplified transmission design and increased efficiency.

Sure, there will be a place in the market for vehicles like yours but it will be a long, LONG, time before anything like that becomes the norm, 2020, 2030, 2040 and beyond.... Look how LITTLE cars have actually changed in a decade from 1998 to 2008 (models are coming out now) in terms of basic propulsion, engines, fuel systems, etc. Go back even further, 1988, 1978, 1968. Geez, Chrysler brought back the Dodge Hemi engine just recently! Even Toyota, the original light truck builder now competes head on with Dodge, Chevy, and Ford with their Tundra! Look at just plain passenger vehicles. The trend has NOT been towards smaller cars, especially when you look at the "import" nameplates, Honda, Toyota, Nissan, Hyundai, but towards larger, more upscale, more powerful and faster vehicles, including SUVs!

Yes, it is possible we may run out of "cheap oil" sometime in the near future, but that will only fuel (pardon the pun) the efforts to finding or creating cheap substitute. Look at the push that soy-diesel and corn-ethanol are getting! Oil from shale (an oily kind of rock which is plentiful in the western US and other parts of the world) is seeing a resurgence as well, as newer technologies and higher imported oil prices make shale oil extraction more cost effective. As petroleum prices get higher, shale oil can be used in many places as a substitute allowing more petroleum to be diverted to gasoline and diesel.

I guess we will always need dreamers, too. So keep dreaming. Just don't confuse dreams with reality!

I think our guest may have been thinking of something like this. More than 640 hp delivered through four wheels would qualify as pretty high performance, I think. No transmission required for 0-16 in 4.5 seconds. His dreams are not too far from reality.

Nevermind the cost to produce this "one-off" demonstration vehicle. Even if a production line was set up to produce it, odds are the costs would be double or triple the equivalent conventional vehicle, particularly when you realize that this is a conversion vehicle and your costs start with the cost of the conventional vehicle (less any component "give-back" discounts you could get from the OEM for return of "new" components removed.

Yes, I am sure there is a niche market for this kind of vehicle. They should sell well in California or London.

A bad starting point in my view. This car already offers just about the worst interior-and-luggage-space/weight ratios on the market!

I agree that it is a pretty silly demo vehicle. It's not as if the market is crying out for a 640 HP Mini. I suppose their point would be to dispel the notion that electric cars are slow, but that point has already been dispelled by the Tesla. Why not make a demo of something people might actually want to buy in large enough quantities to drive down the prices of the wheel motors, which are now astonishingly high, with the price quoted for each wheel motor being close to that of a basic Mini?

The Zap-X (and another super car I can't think of now) are planning to use the PML motors. PML promotes the elimination of wheel brakes entirely, relying only on regen, as a means to bringing down unsprung weight to something reasonable for a heavy car. I'd expect some market acceptance issues with that scheme, despite that fact that it can be made to work reliably, given some system redundancy. If my Saturn controlled braking with its Body Control Module, I'd be dead now: its BCM is horribly unreliable.

Body Control Module? WOw! Where can I get one?

Seriously, that's a term that's never passed by me before.

On the subject of electric motor regen, how does this work at low speeds - I can see how a generator can slow a car down while it's turning, but to stop the thing requires that it can produce a resisting torque at a standstill. I suppose a clever controller can use some current in reverse to actually stop it - or do we rely on friction for the last bit?

I am thinking that the Body Control Module must be the brains of an active suspension, or at least one that changes the suspension configuration for different driving modes. If not properly controlled, this could lead to vehicle rollover at worst and poor steering/handling at best.

Prudence would dictate that we do indeed have some form of conventional friction braking as a back up to the regenerative system, if only for the sake of safety, not to mention convenience, should the electronic controls fail and we still need to drive the vehicle before it goes into the shop for repairs.

Ain't technology wunnerful?

Body control module:

Wouldn't it be great to be able to control other peoples bodies too??

The BCM is the module that controls things like lighting (the overhead light dims slowly, and goes off in ten minutes if you leave the doors open), monitors steering on electric power steering vehicles, detects whether a coded key is in the ignition and will prevent you from starting the car if certain conditions exist* (this part on the Saturn was absolutely infuriating!), etc, etc.

Regen can work at zero speed, given the right logic, but for my own vehicle, it will only work to very low speed, with position holding done by friction brakes (which will also have to come into play in panic stops).

* In the Saturn, one of the conditions it would detect to prevent you from starting the car was this complex one: 1. You wanted to go somewhere, 2. You were in a hurry.