Revolutionary Better Prius

V-Tent is a Solar-Powered EV Charger That Protects Your Car | Inhabitat - Sustainable Design Innovation, Eco Architecture, Green Building

 

From what I understand the output of the current panels is too low & expensive.

 

Why solar? Because you want to reduce emissions, right? Is that part of your ROI equation? How much value did you place on the emissions improvement from the standard ULEV rating to PZEV? There's more at play than MPG alone.


Anywho, that's where I plug-in while working. I have no idea how much of the 82 kWh array (still not fully installed in that photo) is used for the actual recharging, but it's nice knowing something there (most likely, all the lighting within) is using electricity derived on-sight rather than from the grid.

There is actually a set of solar plug-in stations here... of which I keep forgetting to take a photo of... that use a combination of sun & grid for recharging. But that setup likely cost a small fortune. So, it's not exactly an option for consumer installation.

Hopefully, something affordable and large enough will be available to us someday. Currently, that isn't realistic for the masses.

 

Solar panel adds weight too. That has to be considered for safety (rollover test) reason.

What separated PiP from 4 or 5 stars NHTSA rating was the 0.3% higher chance in the rollover test.

The regular Prius earned the overall 5 stars rating with 12.1% risk of rollover. PiP got the overall 4 stars because it had 12.4%. Everything else looks the same. The only difference was 0.3% in rollover test.

Any additional weight above the wheel axle would contribute to the increase risk in the rollover test.

 

Hear me out on this. The amount of solar radiation is NEVER going to exceed 1kw per sq meter (unless you move to another planet). Typical solar cells are currently around 15% efficient at converting that to electricity...with some as high as about 22%. Go up 100-1000x in price and you'll find satellite solar cells about 40-45%. Some say that the theoretical max is 50-60%...that is still only 3-4x better than what you can get today. And on the roof, without a sun roof you might be able to fit one half of a sq meter.

Do the math. A max of maybe 75 watts. I think the actual Prius with solar is about 30 watts.
OK, now consider that, except at the equator, the angle of the sun's rays isn't 90 degrees. Maybe you'll get 3 to 5 hours of equivalent full power in an 8 hour day if the panels are clean and it isn't cloudy. 30 w for 3 hours will give you about 90 wh...enough to go 1/2 mile at 30-40 mph. 75 w for 5 hours will give you 375 wh or enough to go 1.5 - 2 miles. This is being very generous since the charging losses will be large when trying to charge a high voltage battery with such a low voltage source.

If you live somewhere sunny you might get 200 days per year and get 1.5 miles charge per day...or 300 miles per year. All this to save 75 kwh; which at 10 cent/kwh is about $7.50 saved per year. Be generous and make it $10. Even assume you live in a high electric price location and it is very sunny...say it is $25 per year. Assume the very high efficiency solar cells reach their maximum theoretical efficiency and never degrade and are always clean...for no additional cost...and it is $75 per year.

All this savings and Toyota will probably want to charge you $2500 for this option. What a deal!

Mike

 

Loading panels on the car to charge it is not really worth your while. It's extra weight and complexity and more stuff to break and the amount of light that falls on your car doesn't have that much energy.

I think you'd do better having a solar garage. The roof panels would all be oriented correctly all the time, you wouldn't be vibrating your equipment, you could store up a weeks worth of juice and not worry about battery weight or anything.

Since you don't care about size or weight you could collect up a pile of old half-dead Gen. I batteries, store your watt hours on the cheap.

 

Agree totally with all your math and concept. However saying this, one never knows what is going to happen tomorrow. As a kid, I knew a WW 2 vet that traveled up front with Patton as a Radio operator. He was pretty sharp in electronics, as most HAMS used to be. But no formal training. His contention, at the time was, Micky mouse watches with audio communication are impossible. As in Dick Tracy. Video was not thought of even. Remember, he was familiar with 1-3 ft. power tubes that glowed purple and got extremely HOT. The transistor was unimaginable at that time. So never say never. anything is possible. More efficient solar panels will come about OR perhaps something entirely different, totally out of the blue, like the transistor. ( discovered by a new employee, that had no leave time, wondering what to do during the Christmas Holiday. Decided to work on this idea of doping and produced the transistor. A actual miracle!

 

You are confusing this that seemed far fetched or impossible with actual physical limits.
a. On this planet we won't get more than 1 kw/sq meter of sun's energy
b. I assumed 15% efficiency. Assume 100% and see what you get
c. Assume more hours of sunlight (not sure how you are going to get this)
d. Assume a tilting, sun tracking roof (costly and not practical)
e. Assume a roof that unfolds to more square footage (costly and not practical)

Let's redo the math. You have 100% efficient solar cells and one full square meter--thus 1kw. You get 8 full hours of sun (not realistic). So this means you get 8 kw-hrs of low voltage charge per day. And even assume zero losses (it is probably more likely 25-50% at these voltages since you'll need some step up transformers). 8 kw-hrs would be huge -- giving you a good 32 miles of range, or so.

But, practically speaking you aren't going to have more than 1/4 - 1/3 of a sq meter, solar cells on a car roof need to be fixed securely in place, not tracking the sun, solar cells won't ever exceed 50% efficiency by much and probably not greater than ~25% economically, and low voltage charging losses are real. If you are going to purchase solar cells, it makes much more sense to permanently mount them, at a good angle facing the sun and collect the energy from them for 20+ years.

By using the transistor and the amazing things that computers have done in the last 60 years, you are confusing the concepts of energy conversion/transmission and the transmission of information. In energy conversion, every electron moved is required (since that is the point). In computing, data storage and information transmission, essentially every electron moved, sensed or stored (etc) is wasted except one (per bit).

Mike

 

The problem is not the technology. There is just not that much energy within the amount of light that falls on a small car. Even if you catch all of it, it's not enough to run the car.

 

. Perhaps a different solar amplification product or vastly improved Solar storage process. We are only looking at what is now, tomorrow is unknown, uncharted, inconceivable and the naysayers will always say impossible. During the Black Plague it was well known and accepted that cats were responsible for the Plague, so, all the cats were killed. No cats = more rats = more carriers = more Bubonic plague = traditional non factual thought processes prevalent at the time. We of course are a improved version of the 15 Century intelligentsia as we know the amount of solar energy radiating on every square mm of the Earths surface, we understand the ability of Solar panels. Therefore any radical improvement in the solar field is impossible. We are not far removed from the poor souls that lived during the Bubonic Plague. Did you know that many of the scientist that produced the first A Bomb, did not know if it would work, what it would produce? Some thought it might end the World in a Chain reaction. And these were Scientist. I do not know what, is coming around the corner, but I believe it is something good. Anything is possible.

 

How do you see while driving around with that thing on the car?

 

Actually, no it isn't. There are certain laws of thermodynamics that will not be broken, IMO.

Read a few articles on solar and you'll understand that we aren't going to collect more than falls on a given area. Sure, there is lots of work in concentrated solar. But this is all about (for example) taking a one square inch collector and concentrating a square foot of sunlight onto it...therefore a 144x concentration. This is advantageous because you get the sunlight from a square foot, but the cost of only a square inch of a more expensive solar cell. And the efficiency goes up as well...until, approximately, it melts.

But you still need a square foot of collector space. I'm not sure you are really getting this. Unless you want to consider something like unfolding a large inverted umbrella on the roof...the car has only so much available surface area that can be pointed at the sun. We are limited by the amount of sunlight that arrives, and we are limited by the area on the car. One last time...these parameters can't really be changed no matter how hard you believe in future miracles. Just because today's computers seem like a miracle to someone in 1950 doesn't mean we are going to change the laws of thermodynamics.

Mike

 

I agree with your statements, but the laws of thermodynamics are our laws. Man's Law. You are. probably aware that there are some theories floating around by well known scientist that, we have it all wrong and that things work totally different. what we need is Universal Law, established by far greater intelligence than what we can even fathom. This knowledge would come from the outer universe. Even the propulsion systems of UFOs is beyond our comprehension. It is possible that many energy problems, if not all, can and will be solved, when we reach the levels of technology of our fellow space travelers. Not Farfetched but our future.

 

Not a problem, I get these limitations. I would encourage the OP to continue his ideas, he may discover something new.

 

. This is an interesting concept, however, the site gives one zero information just a lot of BS camouflaged in fancy sentences. Some sentences are incomprehensible.

 

Man's laws are things like highway speed limits. Physical laws like the laws of thermodynamics and the law of gravity are man's descriptions of observed and provable behavior. I'm sure I'm probably not stating all this precisely. But if you just want to disregard these laws why not just build a perpetual motion drive train or an anti gravity car?

Mike

 

Until we make permanent and real contact with aliens from outer space, it cannot be proved that all of our scientific laws are really laws of the universe. Many of our own theorems thruout history have been disproven by ourselves, ie: a flat world, man can never fly, even social beliefs : all Indians are savages, there are millions of Bison, the Negro is inferior. Even in recent History ( 500 Yrs) we postulated falsely and finally regrouped and got it right. Some of these ideas were held by millions of people and to dispute them publicly, you were hanged by the KKK, burned at the stake, gunned down in the American west. Many famous old scientist were ostracized , put in prison for thier advanced and different scientific ideas. We have a good basis for Science and I am sure much of it is right, but not all of it. At least we in the free world can speak freely and that is a major accomplishment. But, we are not even half way there.