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Being a computer and network person that I am. It is increasingly obvious that nothing is ever perfect when released. Nearly no amount of product testing can find every possible problem and situation. Nor has there ever been a product that doesn't have room for improvement.

You have to really start to think how nice it would be to reicver a firmware (and/or software) update for the prius. With how much it relies on computers; having an easily user and/or service tech upgradeable firmware would be nice.

There is nothing that says the drive-by-wire can't be made better or more effient or that the interface of the radio or any one of thousands of systems could not be updated to work better, easier or more effiently without the need tp change hardware componants.

For now this is just a pipe dream. In reality they will only release an update if there is a major issue and not just a minor usablity or functionality fix and would infolve updating the CPU of the car or a sperate memory system for the componant and would in actuallity cost more to do thus is not justified.

But who knows maybe in the future it will be more likely toyota will automaticly update your car when it comes in for regular service giving you bettergas milage oand more responsive throtal or better quality or compatible bluetooth.

Who knows.

This goes along with the possiblity of upgrading windows to transparent solar cells and increasing the battery size and thus capsity so more engery can be stored which would be more helpful since the hybrid battery would charge while the vehical is parked and and also slowly charge while the vehical is in opperation causing the gas engine to need to activate less often in slower speeds and provide better milage at higher speeds.

Again still a pipe dream.
 

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Actually, if the entire outside of the car was solar cells, it woldn't make enough electricity to have much impact on the operation of the vehicle, and you'd have to park it outside to notice any difference. Note the KW ratings of the electric and gas propulsors. I have covered 1/3 of the roof of my cab-over camper (largest Lance makes) with solar panels and I get 14 amps at about 14 volts at noon in the desert. This is about 200 Watts or 0.2 KW which is such a low percent of the power levels involved in charging the Prius batts or runing the prius electrick motor as to not be worth doing.

A small solar panel connected by pluging into a power outlet (cigarette lighter) would prevent self discharge and the draw of the security system, etc. from runing the 12 volt battery down. This is quite practical just not a revolution in transportation.

Another useful application of solar electicity is a solar powered window vent. You place it atop a rollup window in the door and roll the window up against it securely. Security is not compromized and the fan draws solar heated air out of the car. This keeps the temp down a lot in the interior which is good for the materials, more comfortable for you on your return, and realy reduces the load on the A/C when you fire up to drive off. Reducing the air conditioner's load is a significant savings as in the PRIUS the A/C compressor is run by a powerful electric motor so you get A/C when the gas engine is shut down and you don't bake your brains out at a long light or train crossing.

Using synthetic lubricants to reduce friction and keppiong tires inflated to max end of the allowed range would likely reduce consumption as much as all the solar panels that would fit on the car would do.

Sorry to be such a "nay sayer" but you might as well look for a cold fusion accessory to plug into the dash to supply clean alternative energy and reduce fossil lfuel usage. It isn''t that the solar energy woldn't help it is the scale of the help and its cost. It is like trying to bail out the Titanic with a thimble.

Pat
 

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I don't agree.

Sunpower are now marketing mass produced solar cells with a 22% efficiency at low prices. (See here: http://www.sunpowercorp.com/html/Company/In The News/Press Releases/A-300_Solar_Cell.html )

With that kind of efficiency, lets say you had only the roof covered in cells (about 2.5m2). In a twelve hour day at average temperate latitude solar flux you could hope to get (2.5x1x0.22x12) = 6.6 kWhrs of electrical energy stored in the battery. Current (sic) battery-electric cars are able to go about 5 miles per kWhr, so you could have effectively 33 miles per day fossil free - or about 12,000 miles per year CO2 zero (more of course if you had the cells on other panels of the car too, or on your house).

However, as mentioned there are two problems with this at the moment. The first is that the Prius motor is only 50kW, so isn't really up to all-electric mode in all situations quite yet. The second is the Prius battery. It has a shamefully small usable capacity (about 0.7kWhr in the 2004), and power output, so would have to be replaced with a decent sized lithium-sulphur pack (http://www.benerridge.freeserve.co.uk/lis.htm ) to be really viable. But then you could conceivably run it for years without ever needing to fill up.
 

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I'm confused, again. You say you don't agree and then essentially lay out a logical presentation of why you do agree. I have considerable practical experience with photvoltaics which never really deliver as much as specsmanship uninhibited ad copy types tout. Don't want to argue, really. If solar cellls would run a car with ample storage to make it efficient but not too heavy then the solar racers in Australia must be a bunch of clods as they don't seem to go fast, have very little energy storrage and sure as hell don't drive much at night.

Really, I am PRO PV just not on fire with a NEW RELIGION. I like my science fiction to be on the screen and in books. Bless you, go forth and festoon your garage with PV and your cars as well. Except in ceratin limited applications, there will never be a payback unless you weight the "GREEN FEELING" quite heavily.

Houses are easier to make practical and get a payback than cars as regards PV. "Home Power" is a widely recognized source of excelent and accurate reporting of PV applications to housing (they get off into biodiesel and electric cars but mostly are house oriented). Look through all the back issues you want and you are hard pressed to find an installation that pays for it self in other than the currency of GREEN SELF SATISFACTION. Remote, grid isolated installaltions may make PV a viable choice but not in competition with the grid.

Similarly, practical electric vehicles, suitable for driving like a Prius DO NOT EXIST. Except for a few short range toys, electric is not practical when it requires charging by other than an onboard generator. I wish it were't so but it seems thus. If solar had such a great opportunity to increase the performance of a Prius, it would probably have solar built in. It isn't like Toyota engineers arent aware of PV technology and this isn't the first year Prius has been built.

Of course someone always has to be first but if it were lilkely that solar could make a practical contribution to a Prius, I would have expected to have seen some evidence of homebrew prototypes long before now.

You stated some of the reasons a Prius is NOT a good candidate. Not enough electrical storage capacity. If you put enough capacity on board then it is so heavy it suffers a mileage hit and the brakes are undersized and the suspension needs to be beefed up and on and on till it isn't a Prius anymore. Credit where credit is due, Toyota got it pretty well right, this time. They chose wisely to have a 11.x gallon energy storage facility (gas tank) that can be recharged conveniently at the easily available existing gas stations. No battery technology at present would allow anywhere near the energy density of a tank of gasoline.

The charge rate available with the useable area of a Prius sized car using PV is way less than the energy demands of moving the vehicle in even slow traffic. Larger batteries and depending on a low duty cycle and long charge times becomes self defeating as it requires massive arrays of PV and heavy batts. It is like the chemical rocket dillema. Most of the rocket fuel is burned to lift rocket fuel. Payload and range are restricted.

Again, thanks for basically agreenig in your previous post. Feel free to educate me, I wish that I was very wrong and that PV cars were currently practical or that a moderate solar panel would bost Prius mileage or that Elvis was still alive, thin and performing or that megawat cold fusion reactors were $1.98.

Note, I'm not against the idea of a PV car, I just don't think the Prius is a good candidate and from your comments, you don't either. :D

Pat
 

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Ah, but remember the solar racers in Australia can go 400 miles in a day. I said the solar flux on the roof of a car only gives enough energy for about 30 miles in a real world sized car. I'm not talking science fiction here, this is just how the maths works out! You're right to point out that the power you get from a roof PV cell is nowhere near enough to run the car while moving (I estimate you'd get max about 600 watts out of it ie just less than 1hp ) but that's not how it would (or could) work.

What I was saying was that if you can store it up in a decent battery, 12 hours of sunlight equates to a lot of energy over a whole day - it's charging from the minute the sun rises till it sets and you're just not driving all that time.

As for the issue of battery weight, I agree that the battery technology recently applied to electric cars (and hybrids like the Prius) is just not up to the job. Lead acid and NiMH are just waaay too heavy for good range. But lithium polymer and lithium sulphur are up to 4 - 8 times less weight, so one day....

As for why PV is unlikely to be used in a car in the near future, it's because the batteries and cells are too expensive and petrol is too cheap!
 
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