Along with more fuel-efficient cars, we need more birth control!

Mark_BC:

One word: Parking

Mark, The surface area of a car is not enough to put enough solar panels on it to allow it to be driven.

The solar problem is that you can't store solar energy in any meaningful way, and there is no sun at night.

You can certainly use solar to boost normal electricity sources, but not replace them, unless you plan on using much less power then you do now.

[ The same problem also applies to wind - variability ]

quote: "The surface area of a car is not enough to put enough solar panels on it to allow it to be driven."

Actually, not true. As I went through the calculation a few days ago, I determined that an electric car in full sunshine all day could go 30 km a day on pure solar energy. This is more-or-less confirmed with experiments on the Toyota Prius, which showed a 15 km range extension from solar panels. With expected increases in performance of commercial solar panels from 15% to, what, say, 40% in the coming decades, that range will jump to closer to 50 km or more -- of free driving!! And of course, anyone who has a home could just throw solar panels on their roof and go 300 km a day if desired.

In one 5 km by 5 km patch of desert in the Southwest, a solar power installation, using currently available PV panels, can produce a half a gigawatt of power. Well, when Saudi Arabia runs out of oil, you know how they're going to end up making energy...

http://en.wikipedia.org/wiki/Topaz_Solar_Farm

Let's multiply this out to 50,000 square kilometers of solar farms. That's 1000 gigawatts. What is the energy demand of the US? (I honestly don't know, someone tell me). 50,000 square kilometers is only 200 km by 200 km. Not very big. The Southwest could support much more than that.

quote: "The solar problem is that you can't store solar energy in any meaningful way, and there is no sun at night."

Sure you can store solar power in a meaningful way -- you, along with 100 million other electric car owners, charge your 500 km range car in the daytime from power harnessed by the likes of the Topaz Solar Farm, then program your car to sell that electricity back to the grid at night until there's 70 km worth of charge left on your car -- enough to get to work the following morning, when you charge it all over again.

quote:
"You have no idea how much energy you have to spend to extract 12 kg of lithium and to make 1Kg of purified silicon or fiber glass"

You may be right, but apparently you aren't aware of how much energy is shining down on us.

I agree though, that parking and space issues aren't so easily addressed.

@mahonj- The surface area of a car is not enough to put enough solar panels on it to allow it to be driven.

Even hear of the solar car race?

BTW It's electrical energy that you can't store in any meaningful way. Solar thermal power plants can and do operate at night. And wind is only variable when you look at it as a local energy source. When you think of wind as a regional energy source things change- http://www.stanford.edu/group/efmh/winds/aj07_jamc.pdf -
Many regions of European countries integrate up to 40 percent wind power successfully. An August 2007 review of actual windpower integration by utilities in your country, "Utility Wind Integration and Operating Impact State of the Art," found that the integration cost in eight different major wind projects, ranged from 0.2 to 0.5 cents per kwh. Moreover, as we electrify transportation over the next two decades with plug-in hybrids, the grid will be able to make use of far larger amounts of intermittent, largely night-time zero-carbon electricity from wind.

And what makes you thing your current energy providers aren't variable?- http://www.onlineopinion.com.au/view.asp?article=6958

Hey I wonder if you could combine a solar and wind farm into the same area?

Mark
You could combine solar and wind into the same collector. The idea is called a tornado/vortex tower- http://books.google.ca/books?id=Z4bhObd65IAC&pg=PA74&lpg=PA74&dq=vortex+tower&source=web&ots=RLivCMnRH3&sig=rHNtxM6Ioz4PBvhhXhNRbbH6z10&hl=en&sa=X&oi=book_result&resnum=3&ct=result#PPA75,M1 -there's even something called an updraft tower- http://en.wikipedia.org/wiki/Solar_updraft_tower -but the cost of building such things would make them unlikely in the near-term.

Heard a comment that re current fiscal crisis that the amount of money counted in all the derivitives etc amounts to more than all the real money in the world or that while we may have more on paper than ever before, there are a finite no of quality assets, hence the money flows out into high risk or fake assets.

If we consider the requirements of other species for healthy viable populations and the fact that these have been under pressure fro human activities for centuries, leading to extinctions.
We see that reducing pressure on the natural environment/ habitat is necessary given that we understand diversity and sustainability are a reflection of the health of our environment.

In the simplest form When indicators show other species under threat we know we are not apart.

Carlos Goshn is a cornucopian.
The number of vehicles is not going to be 4 times bigger by 2050.

Why there are no more investments in new refineries ?
because global Peak Oil is now, or within 4 years !!

"Anyone who believes that exponential growth can go on forever in a finite world is either a madman or an economist"

The surface area of a "real car" is NOT enough to power it using solar cells.
You can get a solar kit for a Prius, and it generates 215 watts.
http://www.groovygreen.com/groove/?p=3063
If you get 7 hours of useful sun / day, you get about 1.5 KWH of energy which is about enough to drive 6 miles at 4 miles/kwh, which is a very high figure.
That equates to about 2200 miles / year which isn't much use to anyone.
If you want to charge an EV from solar panels, go ahead, just don't try to stick them on the car.

The solar racers are not practical cars, they are racing cars which is very different; you can't go to Wal Mart and do a weeks shopping in them with the family (which you certainly can do in a Prius), and especially not when there is no sun.

Wind is variable over large areas - you get winter inversions in the Uk and Ireland where you get No wind for 5-6 days in a row once or twice every winter: you cannot store enough energy to cover that, you just have to use fossil fuels.

The only reason Denmark has so much wind is that they can both sell excess to Germany and use hydro from Norway to buffer it when they have no wind themselves.
Even so, they only get 20% of their energy from wind.

Wind and nearby hydro go well together, wind cannot work on its own, or just with solar, it needs some other buffering source.

As people point out, you can use PHEVs to time shift power from night rate to peak times, as long as they exist in large numbers which they don't, and that you don't drive them at peak times.

If I had a PHEV, I would want some convincing that I should use extra battery cycles to do a little time shifting for the utility - I would certainly charge it at night, but I would not let people discharge my batteries without good reason - presumably the resale value of a PHEV will depend on the number of charge/discharge cycles the battery has gone through.

The Nissan/Renault Kangoo plug-in hybrid electric vehicle gets about 150 watt-hours per mile. The roof could hold about 700 watts of solar PV. With 4 hours of full sun, the Kangoo could go 16 miles a day on just sunlight.
Alternatively, you could mount 2 kW (200 sq.ft.) of solar on your garage, produce 2400 kWh of on-peak power during the day and charge the Kangoo batteries with cheap off-peak power at night. Utilities like it because it reduces summer loads and utilizes plentiful off-peak power at night. 2400 kWh is enough for 15,000 miles of all-electric driving per year (40 miles/day).

quote:
"If you get 7 hours of useful sun / day, you get about 1.5 KWH of energy which is about enough to drive 6 miles at 4 miles/kwh, which is a very high figure.
That equates to about 2200 miles / year which isn't much use to anyone."

Well you're taking the naysayer's approach, using only current technology and not allowing for significant improvements over the next 10 years, and using lowball numbers. The EV1 got 10 kWh / 100 km which equals about 6 miles / kWh, not your 4. So that brings the range to 9 miles a day.

And that Prius add-on solar panel you referenced only covers the roof. If it were to be integrated into a vehicle's body during manufacture, and also cover the hood on the front, you'd get more power. And then get some flexible roll-up panels that go on your windows when you're not driving. It's all pretty basic stuff, on the market today.

I wonder why there's so much resistance to accepting simple calculations which clearly show how much is possible if you simply try to do it and make improvements all around.

Regarding lithium scarcity, I haven't looked into that. You are probably right. But I have a feeling we'd find a solution somehow.... I mean, when has an economist or business person ever decided to NOT venture forth in fears of a POTENTIAL overuse of resources in the future? LOL It's almost an oxymoron. If we reach a lithium supply crunch, well I'm sure some other options will become available when the necessity breeds the invention.

quote:
"cover 600 * 600 kms of desert with solar panel is a challenge like humanity has never faced before."

It would actually be significantly less because there are so many houses and warehouses in the southwest that would be happy to put solar panels on their roofs if it was economically worthwhile. The 600 km by 600 km figure is simply to put it all in scale.

Let's see here, if there were 100 million electric cars on the grid (not an unrealistic figure in 20-30 years if GM actually does start producing them now), each capable of storing 200 km of charge, at 10 kWh per 100 km, that equals 2000 million kWh. This would need to be used over a 12 hour night time period, so that's 150 million kW, or 150 gigawatts, in comparison to the US energy use of 3.3 terawatts. Now, I'm guessing that 3.3 terawatts is averaged over the whole day, so at night the usage would probably be significantly less, let's drop it to 1 terawatt. So our electric cars plugged into the grid could provide 1000 / 150, or 15% of the energy needs of the nation at night. Not very high, but significant enough that it could be used to even out the intermittencies of wind power.