Why buy a Prius now, when-

Toyota will soon come out with a built-in solar photovoltaic roof panel on the car and a bigger capacity battery! Depending on how much sunlight falls on the panels why being driven or parked- you'll get up to 30 miles on FREE SOLAR ENERGY from the battery alone- before the gasoline motor kicks in!

Reply to
misterfact
Loading thread data ...

How nice.

Of course this doesn't address the fact that as far as infrastructure needed to purchase, drive it around and dispose of it when it's worn beyond repair - roads, concrete plants, parking lots, automobile factories, landfill space - it consumes as much resources as a Hummer. The difference in fuel use while driving it, while obvious at the pump is negligible in the overall scheme of things.

Purchasing a sound used car in good condition that's already been through the manufacturing process, is far cheaper than a car payment and a smaller gasoline bill even if it consumes a lot more gas. It's also a much wiser use of resources than trading in your current (fill in the blank) for a new Pious, if that sort of thing concerns you.

Or, you can continue to be part of the problem and consume consume consume, while deluding yourself and assuaging your guilt by telling yourself that the hybrid is going to make a difference.

-- Mike Harris

95 Tacoma 2WD 87 Corolla hatchback 63 Willys Jeep wagon, SBC conversion Austin, TX
Reply to
Mike Harris

The only study I've seen on that makes the laughable assumption that the Prius owner will be pitching it onto the scrap heap at 100,000 miles and that the Hummer will last at least 300,000 miles. R-i-i-g-h-t.

Reply to
DH

Got a reference for this? It seems to me that the solar panels are only going to add significant energy when the car is being driven. It is my understanding that the Prius battery is kept in a high state of charge while the car is in use, so it seems that the solar panels can't add much energy while the car is just setting there (you would usually only be topping off the last 5 or 10% of a charge in most situations). I suppose a software change could allow the batteries to be discharged much further, but that is going to adversely affect the life of the batteries. The amount of solar energy collected while the car is in use is going to be trivial for most people in most situations. It seems to me that the disadvantages of having a car covered in solar cells will far out weigh any benefits.

Ed

Reply to
Ed White

Hybride car is not an alternative! The number one reason for the low gas mileage is low power-to-weight ratio. So, in order to save the gas, we all need to switch to Geo Metro or the old forgotten air-cooled Honda or, at least , the BMW Isette. But as long as the full size monsters are on the road and/or dangerous drivers are behind the wheel, driving the subcompact car is unnecessary heroism. In Europe, for example, only weathy people could drive the big cars.(This does not mean that they are the good drivers, but at least they could pay for liability damages).

Reply to
Doctor J

Why would the solar panel only add significant energy when the car is being driven? Since most solar panel applications are not automotive-related, I would think that driving the vehicle would not have any effect.

Reply to
Ray O

It's like people who insist on using recycled paper. To make recycled paper a nice white again requires MORE resources than just starting with trees and making white paper.

But people are stupid, and they focus on only one little part of the entire issue. That's what makes marketing people successful--they can heavily market to that little part of the buyer's brain that's working.

Reply to
Elmo P. Shagnasty

You need to get your mind out of the fuel tank, DH. Regardless of the expected life of either vehicle, they still consume the same road space, parking space and so forth.

Compare fixed costs vs variable costs. Let's for the sake of argument call it fixed resource consumption vs variable resource consomption for clarity. An economist would quibble that they're the same thing but it'll make it easier to comprehend for those liberal-arts majors and greenies who like to believe that finite resources should be allocated in some other manner besides price - "from each according to his abilities, to each according to his needs" sounds equitable and has a nice ring to it, but I digress.

While the variable resource consumption is less with the Pius - and it's incrementally less, not by anything significant like an order of magnitude - the fixed resource consumption is the same and by far counterbalances the variable resource consumption of ownership. As anyone who's ever priced paving a private road can tell you.

Ask not who the paving machine runs for, Pious Driver - it runs for thee.

-- Mike Harris Austin TX

Reply to
Mike Harris

Ray,

It has to do with storage capacity.

If the ECM keeps the battery bank as close to a full state of charge as practical (and for the sake of battery life I don't doubt that this is the case) the solar cell won't have anywhere to put the small amount of energy it generates.

On the other hand, while moving the electric drive system is consuming power , so the solar cell has someplace to put the energy it's generating - for what little it's worth.

Keep in mind the low output of solar panels. A 150 watt panel is pretty sizeable but this is only about 12 amps and everything has to be perfect to get that sort of power. Figure half that - 6 amps. Compare this to the amperage put out by an average alternator, let alone the charging system in a hybrid.

A solar panel on a hybrid is nothing but a "warm fuzzy" for the nut crunch bunch.

-- Mike Harris Austin, TX

Reply to
Mike Harris

Does storage capacity change if the vehicle is moving?

The ECM does not keep the battery bank as close to a full state of charge as practical. It keeps it somewhere between 45% and 75% charged.

I am not saying that you are right or wrong, however, logically, these 2 paragraphs are disconnected. Both paragraphs are factually and conceptually correct, but they do not prove or disprove your assertion that a solar panel panel is more efficient if the vehicle is moving.

Perhaps my understanding of the concept of efficiency is flawed, by my understanding is that if something is more "efficient" it has to do more work with less energy consumption or it has to do the same or more work in less time.

Since a solar panel does not consume energy that we have to provide it, for it to be more "efficient," it has to provide more electricity over the same amount of time or provide the same electricity in less time, or more watts.

How does placing a load (in your explanation, the electric motor) on the solar panel make the panel produce more watts than if the load were a replenishing the charge on a battery?

I tend to agree with this sentiment, but not because the panels are more efficient when the engine is running.

Reply to
Ray O

Photovoltaic panels work with light not just sun, and they are very expensive. Nothing is free and I wonder if the panels will be cover by ones comprehensive coverage. I once considered using photovoltaic panels to generate enough electricity to power my home in Key West. The property was not big enough to install enough of them to do the job and the cost was astronomical. I could not ever have recovered the cost in electrical rate savings in my lifetime. I did install a system to heat water but it too was expensive, over 17K and volume in limited. My home owner insurance does not cover damage to the panels ;)

mike hunt

Reply to
Mike Hunter

Better yet go to a junk yard to get your next car. That way you will help recycle the cars and you can buy recycled parts there as well to save even more money and help to save the environment. Look for a diesel, you can run it on free cooking oil from McDonalds ;)

mike, hunt

Reply to
Mike Hunter

Let me see if I understand what you are saying. In Europe the rich drive big cars and the not so rich buy small cars, correct? Sound a lot like the US to me.. I do not know anybody that can afford a big or luxury car that drives a cheap small car ;)

mike hunt

Reply to
Mike Hunter

Those old forgotten air-cooled Hondas were great for the environment because they did not have emissions control equipment to clutter up junk yards, and of course, the average driver was much better at setting the manual choke to avoid rich or lean mixtures ;-)

Reply to
Ray O

You're going to have to define your idea of fixed vs variable resources.

For example, one of your resources - pavement use - is, in fact, unequal between the Hummer and the Prius - the 3000lb vehicle has significantly less impact on road wear than the 6000 lb vehicle. The Prius can use a compact parking space (popular in ramps) that the Hummer can not. Heck, there's ramps around here that don't have the height clearance required by the Hummer.

As I said, the only studies I've seen that "prove" the Prius is as resource-intensive as a Hummer make absurd assumptions.

Reply to
dh

At present, it works that way. Why not make an partial SPV vehicle's systems aware of the time of day to maximize use of solar energy? Why not itnegrate topographical data with the vehicle's nav system to allow the battery to run down optimally by the time it crests a hill and recharge regeneratively on the downslope during a trip? Why not allow the battery to deplete optimally when heading for home and a grid recharge?

Reply to
dh

My insurance company does cover solar panels installed on the home.

Maybe you should shop around.

Reply to
dh

Ray,

Sorry, I should have clarified. The panel itself isn't less efficient at producing power when the car is parked; the power that's produced is more likely to be used instead of wasted when the car is moving because charge rate on a battery isn't linear.

As a battery approaches full charge, and depending on the type of battery this effect starts generally anywhere from 65-80% of maximum charge, a greater percentage of the energy goes to heat while a lesser percentage goes to energy-storing chemical reactions.

The solar panel will, for the most part, produce the same amount of energy whether the car is moving or not. However, with a linear-consumption load on the circuit (be it the electric drive motor, AC, lights, radio etc) the wattage produced by the panel goes to that load. When the car is not moving, and with the battery at anything over about 3/4 charge more or less, any energy the panel generates will go in part to charging the battery and in part to heating it

Additionally, the ECM will likely either shut down the panel or shunt its current into a dummy load to protect the battery bank from damage once it reaches a full charge state. This would only happen when the car is stationary; at that point any sunshine on the panel is lost.

-- Mike Harris Austin, TX

Reply to
Mike Harris

In the late 1980s a UK company designed a hybrid for the *.ca.us market which went a _little_ way to doing that. On entering, the driver told the car whether it was to be a short trip, or a long one. The car then used different strategies to suit. The same car had PV cells on the roof to gather energy that drove weak a/c that reduced the cabin temperature whilst the car was parked; no a/c was provided when moving, though. Never heard what happened to the car; I suspect it failed and got absorbed into the world's fund of experience, which happens all the time (even to cars like today's Prius, which will be replaced by better future designs).

Reply to
Andrew Stephenson

Got a "D" in econ, did you?

Fixed cost - one that does not change with a change in output. Your car payment is the same whether you drive it around or it sits in your garage. Variable cost - one that does - the more you drive the more gasoline you use. This is the Romper Room, Econ 101 version - you might have a mileage capped lease but I digress.

It doesn't seem that you did so well in math, either.

The difference in resource consumption between the two vehicles is insignificant. Even if, as you argue, it's a factor of two - twice as much fuel, twice as much road wear, twice as much parking space - this means nothing. While we can debate whether the Hummer is 10% or 50% less efficient than the Pious, compared to the total resources allocated to build a vehicle - ANY vehicle - and provide for its care, repair and feeding, an efficiency difference of anything less than an order of magnitude is meaningless.

I'm not attempting to prove - or even to suggest - that the Pious is as resource intensive as the Hummer - it's clearly not, as any idiot can see. I'm trying to point out that the difference between the two is irrelevant.

Depending on who is doing the estimating, between 12 and 20% of the US economy directly supports the automotive industry. I couldn't find any numbers that might estimate the total impact including indirect support - but you certainly have to agree that it's a significant percentage in any case.

Not that I'd want to try and excise that from our economy, of course. There are a lot of other industries - residential construction, retail sales just to name two off the top of my head - that are heavily dependent on the automobile. That's right - suburban sprawl is a direct result of our car culture, and if I really wanted to be an assh*** I could make the argument that more fuel efficient cars worsen sprawl by encouraging people to buy houses further away from where they work. If you had a Hummer you'd think twice about doubling your commute distance, right?

So - got it? Feeling good about yourself for driving a Pious, or feeling guilty about driving something less efficient, or getting angry at those who don't care about the planet because they're driving big honking SUVs, are all irrational responses.

-- Mike Harris Austin, TX

Reply to
Mike Harris

MotorsForum website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.