SEP 21

It's time we get off this "one solution fits all" mantra. The solution for our energy concerns has to be multi-pronged.

-- Solar energy, both residential and utility.
-- Wind energy.
-- Natural gas-fired power plants.
-- Nuclear power, in a pinch (I say this most reluctantly).
-- And, most importantly, cutting back on home and business power consumption.

How would DC transmission help with efficiency?

DC power is difficult to transform to a higher voltage, and the real killer in long-distance transmission is the amount of current. If you want to carry a given amount of power over long distances, the best thing to do is to transmit it at high voltage, which has traditionally meant using a transformer.

The only thing I can think of is the fact that some eddy currents and capacitive charging dissipate energy along the length of the wires.

Even if we grant that a DC line would be more efficient for long transmission runs, why on Earth would you want to switch over to DC power for the whole grid? If you're transforming DC down to a lower voltage (as you would at the consumption-end of the proposed long-distance transmission lines), it's generally necessary to convert it to AC as part of the process. In other words, it wouldn't be difficult to connect these lines to existing infrastructure.

Not to doubt this Mills guy, but as I understand it, DC isn't practical for long-distance transmission. Distance requires high voltages to avoid power loss. But high voltages blow up consumer electronics. With AC, you can step the voltage up to transmit and down to make it work.

So I wonder how accurate their facts are.

Also, anybody got thoughts on the environmental impact of 92 square miles of daytime heat sink and nighttime heat source? Certainly can't be good.

I'm liking the multi-pronged, best-for-the-locale distribute-the-generation load idea, I think.

I believe that figure should be a 92 mile square (8500 mi^2), not 92 square miles (see http://en.wikipedia.org/wiki/Square_mile).

I think Ron W's on the mark with his approach.

I belive that even a 92 mile square would still only be approximately the size of the Phoenix AZ metro area.

I've heard of the same plan using North-African super hot weather to produce thermal solar for Europe.
The idea of DC current was also used for the long distance (ie main lines) with DC at the end.
This mean work and cash for Africa, technology business and (more) reliable power for Europe, good deal for both :-)

I don't imagine we'll get full support from the government until these oil cronies have had their fill of the oil pie. Until then the GOV will do everything they can to stifle or delay progress into this area (unfortunately). Obviously it IS possible to power all of our energy needs with renewables.

Sorry... There is NO good reason to use DC over long distances... anyone who has ever studied electricity will tell you about DC Has more losses ( ie more resistance ) per foot traveled than AC does at the same current or voltage... the AC system is already in place.... And if you are using solar thermal to produce the power ... you are still just turning a turbine which can produce either DC or AC thus no conversion is needed, just produce AC directly... If long distance losses are an issue do what the power system does already, and crank up the AC voltage even higher for transmission and then back it down when it gets near suburbia ...

Great comments:
We could also built a solar plant in the Navajo reservation thus enabling them to make money,support the earth and keep their culture.
Don't forget wave energy from the ocean.

Actually, there are long distance high voltage DC transmission lines in operation in the US. DC has one advantage over AC today in that you don't have to worry about the voltage being in sync on the grid. i.e. What we had happen in Ohio and caused a nice large blackout a few years ago wouldn't happen with a DC grid. I still see no reason why a DC grid would be required for this, though.

Now, Alex@EnergyPlanet, what do oil companies have to do with this? This will generate grid power, something only a miniscule ammount of oil is used to generate. It makes no sense that they would even care about this.

Someone else discussed long-distance transmission, which is a great idea.

The other response is that if we use clean energy like solar as many places as we can, if we have to still use dirty sources like coal or whatever in other places, the harm is at least diluted because it is a smaller percentage of the total generating capacity.

@EV why do the oil companies care?

Because they stand to lose millions every day if you stop using it. and they have the money to do all the buying of senators and presidents that they need to make sure your solar power future doesnt become a reality until the oil reserves are all but gone and they cant make any more money.

its a shame your countries decision makers can just be bought off. the world might have been a nice place without them

i like this idea, dont get me wrong. but, would it not be better and more efficient/cost effective for the individual to have their own solar generator on their own property? no monthly payments.

@Nokia N95 Owner,
If I am not mistaken petroleum represents less than 2% of the US power grid production.

http://www.eia.doe.gov/cneaf/electricity/epm/epm_sum.html

That does seem about right - or more believable i suppose. As the US is 3.7million square miles in total and that comes to 8,464 square miles if its actually miles squared and not square miles. Good catch. ( if its right :D )

This is so far off base it is incredible. First of all, there is no way it could be 92 square miles. That would only be ~9.5 miles x ~9.5 miles square. If he meant it should be 92 x 92 miles, then that is still probably way too small. That would be ~8500 square miles for just over 300 million people. If you do the math ((92^2/300000000)^(1/2)*5280) that equals a 28 foot x 28 foot section of solar per person. I highly doubt that that small of an area could really provide all of my energy needs with today's solar technology. I'm all for renewable energy, but lets be real.

The suns power density on the surface of the earth is approx 1.3 kW/m^2. ( http://hypertextbook.com/facts...ndit.shtml ) 28 feet * 28 feet = 784 square feet => 72.8 square meters * 1.3 kW/m^2 =~ 101 kW per person. you use on average around 10 - 20 kW, so yeah, this is reasonable. Thats 100% conversion efficiency, but even at 50% conversion, thats ~ 50 kW per person, still perfectly reasonable.

Your calculations are wrong...

92x92 = 8464 square miles.
This is 92(5280) x 92(5280) = 2.36x10^11 square feet.
Divided by 3,000,000 is 78,654 square feet per person.
This is about 1.4 football fields per person, or 280 ft x 280 ft per person, not 28x28.
that's a HUGE amount of land.

Even at 92 square miles = 9.6 miles x 9.6 miles = 50,688 ft x 50,688 ft = 2.57x10^9 square feet
Divide that by 3 million and that gives 856.42 square feet per person, which gives your 29.3ft x 29.3ft per person.

Solar power plants follow the "economies of scale" model as well, which means the bigger they are, the more efficient they are.

Tucson Tom...check again, Phoenix city is over 500sq miles, metro is over 9000. Tucson metro is over 600. Use Flagstaff (~65sq miles) as a comparison point.

And I read somewhere that to power the whole world on solar, all that's needed is a land area the equivalent of Iraq. However no-one's been brave enought yet to ask the Iraqis if that would be a better use of their country...

This article needs a couple of corrections. First of all, the proposal was for an array of solar reflectors measuring 92 miles by 92 miles. That equals 8,464 square miles, not 92 square miles.

And the closing statement about "rethinking the carbon-biased infrastructure" is ill-informed. The AC transmission lines of which the author is writing were brought to popularity with the rise of hydroelectric power generating plants, which are carbon neutral.

The reason we use AC in the first place is because its better for transporting long distances, why would we switch to DC? It's just using steam to power a turbine, just like coal, gas, and nuclear. So why DC?

Wow, ONLY 92 sq miles? And I'm guessing these solar panels WON'T be going on land that other power plants used to be on right? Because they don't get enough sunlight. I'm guessing the space you're going to need for this is probably going to result in clearing more forests. Wow, souds pretty "green." Also nice how you don't include any info about the horribly destructive and resource sucking process that has to be done to make solar panels. As long as we can power our vacuum cleaners, come hell or high water, right?

Just so you know, the REAL defenders of this Earth will fight any energy project, "green" or conventional, that threatens this Earth anymore. Stop tiptoeing around the real issue, which is that this society is unsustainable. Do you know what it means when something can't be sustained? It means it is going to end, and when the current one ends, we don't need you sustaining the worst technologies and continuing the same system with solar power, nor wasting the land to do so.

"I'm guessing the space you're going to need for this is probably going to result in clearing more forests."
Yeah! There are lots of trees in Arizona and New Mexico!

You're all wrong. I wish I could remember all the exact details, but I will give a synopsis. High voltage AC is somewhat efficient at long distances, but very high up in the air. I forget at what voltage, but at a certain point, DC becomes MUCH more efficient. And we're talking about right on the ground, or underneath. Much easier for infrastructure. And, btw, they're talking about taking the DC and transmitting it, then putting it through a transformer and converting it to AC at the destination. Highly efficient.

Some people think they know everything.

because he didn't RTFA. They aren't solar panels, they're just using solar energy to heat water to drive turbines.

@ Only?

"Clearing more forests" for solar? What are you smoking? Do you even think about things before you write them?

Large scale solar farms aren't put in places with forests. Forested areas have lots of rain and clouds. Solar doesn't work too well in cloudy areas. That's why all these big solar farms are put in places with lots of bright sun and almost no inclement weather. Places called Deserts.

A square, 92 miles on a side, or about 8500 square miles. (the title of this submission REALLY needs to be changed to 8500 square miles of solar...) So some lizards in Nevada or Arizona would have a bit more shade. But it probably wouldn't impact their lives too terribly.

As for transmitting all that juice to the north east, by far the most efficient method would be high temperature superconducting cables. These cables have almost no electrical resistance, but do have the downside of requiring liquid nitrogen refrigeration. Even building in the refrigeration costs, power loss would be halved. Test cables of this sort are currently being built.

But 8500 square miles of solar arrays (or anything) would probably never be cost effective. The best way to get costs down is to increase efficiency of the collectors, thus reducing the necessary footprint. I think 3 technologies need to converge before any realistic attempt could be made to convert the US to solar.

Far more efficient solar collectors
Superconducting, trans continental transmission lines
Efficient energy storage systems would be mandatory. These storage systems would have to directly power the nation ever night.

Night time is, and probably always will be the biggest stumbling block in any move towards total solar conversion.

I am ingnorant when it comes to this stuff. I dont know what half of you are talking about but love that you are. Keep up the good work and maybe we will come up with a solution after all! :)

â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â
–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘
░░████████████████â
–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–‘â–‘
░░████████████████â
–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–‘â–‘
░░████████████████â
–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–‘â–‘
░░████████████████â
–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–‘â–‘
░░████████░░░░░░░░â
–‘░░░░░░░████████░░
░░████████░░░░░░░░â
–‘░░░░░░░████████░░
░░████████░░░░░░░░â
–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘
░░████████░░░░░░░░â
–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘
░░████████████████â
–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–‘â–‘
░░████████████████â
–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–‘â–‘
░░████████████████â
–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–‘â–‘
░░████████████████â
–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–‘â–‘
â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â
–‘░░░░░░░████████░░
â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â
–‘░░░░░░░████████░░
░░████████░░░░░░░░â
–‘░░░░░░░████████░░
░░████████░░░░░░░░â
–‘░░░░░░░████████░░
░░████████████████â
–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–‘â–‘
░░████████████████â
–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–‘â–‘
░░████████████████â
–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–‘â–‘
░░████████████████â
–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–‘â–‘
â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â
–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘
░░████████░░░░░░░░â
–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘
░░████████░░░░░░░░â
–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘
░░████████░░░░░░░░â
–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘
░░████████░░░░░░░░â
–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘
░░████████░░░░░░░░â
–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘
░░████████░░░░░░░░â
–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘
░░████████░░░░░░░░â
–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘
░░████████░░░░░░░░â
–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘
░░████████░░░░░░░░â
–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘
░░████████░░░░░░░░â
–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘
░░████████░░░░░░░░â
–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘
░░████████░░░░░░░░â
–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘
░░████████░░░░░░░░â
–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘
░░████████░░░░░░░░â
–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘
░░████████░░░░░░░░â
–‘░░░░░░░████████░░
░░████████░░░░░░░░â
–‘░░░░░░░████████░░
░░████████████████â
–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–‘â–‘
░░████████████████â
–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–‘â–‘
░░████████████████â
–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–‘â–‘
░░████████████████â
–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–‘â–‘
â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â
–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘
░░████████████████â
–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–‘â–‘
░░████████████████â
–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–‘â–‘
░░████████████████â
–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–‘â–‘
░░████████████████â
–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–‘â–‘
░░████████░░░░░░░░â
–‘░░░░░░░████████░░
░░████████░░░░░░░░â
–‘░░░░░░░████████░░
░░████████░░░░░░░░â
–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘
░░████████░░░░░░░░â
–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘
░░████████████████â
–ˆâ–ˆâ–ˆâ–ˆâ–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘
░░████████████████â
–ˆâ–ˆâ–ˆâ–ˆâ–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘
░░████████████████â
–ˆâ–ˆâ–ˆâ–ˆâ–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘
░░████████████████â
–ˆâ–ˆâ–ˆâ–ˆâ–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘
░░████████░░░░░░░░â
–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘
░░████████░░░░░░░░â
–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘
░░████████░░░░░░░░â
–‘░░░░░░░████████░░
░░████████░░░░░░░░â
–‘░░░░░░░████████░░
░░████████████████â
–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–‘â–‘
░░████████████████â
–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–‘â–‘
░░████████████████â
–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–‘â–‘
░░████████████████â
–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–‘â–‘
â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â
–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘
░░████████████████â
–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–‘â–‘
░░████████████████â
–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–‘â–‘
░░████████████████â
–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–‘â–‘
░░████████████████â
–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–‘â–‘
░░████████░░░░░░░░â
–‘░░░░░░░████████░░
░░████████░░░░░░░░â
–‘░░░░░░░████████░░
░░████████░░░░░░░░â
–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘
░░████████░░░░░░░░â
–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘
░░████████████████â
–ˆâ–ˆâ–ˆâ–ˆâ–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘
░░████████████████â
–ˆâ–ˆâ–ˆâ–ˆâ–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘
░░████████████████â
–ˆâ–ˆâ–ˆâ–ˆâ–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘
░░████████████████â
–ˆâ–ˆâ–ˆâ–ˆâ–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘
░░████████░░░░░░░░â
–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘
░░████████░░░░░░░░â
–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘
░░████████░░░░░░░░â
–‘░░░░░░░████████░░
░░████████░░░░░░░░â
–‘░░░░░░░████████░░
░░████████████████â
–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–‘â–‘
░░████████████████â
–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–‘â–‘
░░████████████████â
–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–‘â–‘
░░████████████████â
–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–‘â–‘
â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â
–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘
░░████████████████â
–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–‘â–‘
░░████████████████â
–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–‘â–‘
░░████████████████â
–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–‘â–‘
░░████████████████â
–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–‘â–‘
░░████████░░░░░░░░â
–‘░░░░░░░████████░░
░░████████░░░░░░░░â
–‘░░░░░░░████████░░
░░████████░░░░░░░░â
–‘░░░░░░░████████░░
░░████████░░░░░░░░â
–‘░░░░░░░████████░░
░░████████████████â
–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–‘â–‘
░░████████████████â
–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–‘â–‘
░░████████████████â
–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–‘â–‘
░░████████████████â
–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–ˆâ–‘â–‘
░░████████░░░░░░░░â
–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘
░░████████░░░░░░░░â
–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘â–‘
░░████████░░░ââ

your figure is incorrect: it's not 92 square miles, but a 92x92 mile square-- that's 8464 square miles. Check out the facts at www.ausra.com

very interesting ... but not sure whether it will work or not ..

d

Having studied the matter for over 2 decades, I'm always saddened by the number of so-called experts that try to stamp out this idea. It's the most plausible solution, and yes, it is very capable of being a one-shot answer to virtually all of our energy problems.

Over 80% of the energy that comes here from the sun, is heat. Conventional solar panels only derive energy from light, and only a small fraction of that fraction actually makes it into the wires. While Photovoltaics have their place, mass energy production isn't it.

Using the heat from the sun, is jsut like using the heat from a nuclear reactor or natural gas. It's used to make steam to spin a generator in all cases. All that changes is the source. You want fusion? The sun is fusion.

This idea, while numbered optimistically, could be doubled for any difficulties. I would very well work, with no supplements. If only the nay-saying 'experts' would shut up and get out of the way...

Question: Any reason these solar plants would have to all be in big block? Doesn't have to be square. Doesn't have to be connected. area is what matters, right?

Population is 300,000,000 not 3,000,000 so your numbers are off by a factor of 100. On top of that, you are assuming that power is available 24hrs a day. Assume ~6hours of production a day for solar while the numbers you are thinking about are for all 24. Solar can help but it needs to get much more efficient and much less nasty to produce the equipment. One of the best solutions would be to figure out a way to store power as off peak generation could be kept going to offset peak consumption which would reduce if not eliminate the need for oil / coal plants.

What's so bad about nuclear energy?

First off - Goober is right about DC not being the appropriate choice for long distances.

Second - Everyone always overlooks the environmental impact of something like this, they think solar renewable = great! not so much when you think that you would have to upkeep 8464 sq miles of silicon that is used in the PV panels. Once the panels deteriorate they have to be disposed of - not a great solution.

Finally - I would rather see them put the money towards nuclear power. The day they produce fusion plants is the day we move past our energy problems. (Yes I am fully aware of the issues they are currently having with fusion power, which is why I think money would be better spent funding fusion research rather then calculating how many thousands of square miles of solar panels we need.)

--
Max ... Out!
http://www.cmyos.com - free online operating system

More energy has to be generated at the local level ie individual houses, office buildings etc rather than wasteful mega power centres. More efficient building design and changing personal habits would also help. Wouldn't it be great to get rid of all those power lines that criss-cross the country?

AC transmission loss at 50% ? Nonsense. AC transmission losses in the U.S. are much closer to 3%...

Nicoli Tesla; Where are you when we need you!

Wikipedia has an entry about High-voltage direct current, or HVDC. The URL is en.wikipedia.org/wiki/HVDC
The article lists the advantages of HVDC.
PowerPedia has almost the same article, but also mentions the health benefits of HVDC. www.peswiki.com/index.php/Direct_current
The War of Currents article gives a reason for the greater efficiency of direct current, called the "skin effect."
en.wikipedia.org/wiki/War_of_Currents
The lack of DC transformers is what settled the War of Currents, not any supposed greater efficiency of AC transmission.

I am much dumber now after reading these comments.

"you would have to upkeep 8464 sq miles of silicon that is used in the PV panels"

RTFA Nuclear, the system uses HEAT not PV.

And you nuke lovers, consider there are 2 bad choices for nuke waste: leave it in the front yard or truck it across the USA. Both suck.

And the economics of nuke energy are a lie. Insurance, security, inevitable disaster costs, decommissioning, and storage of waste virtually forever are never calculated.

My estimations based on what we think the article meant to suggest, are as follows;

92 miles squared is 92 x 92 = 8,464 square miles, being 13,621 square kilometres, being 116.71 kilometres squared. i.e. 116.71 km x 116.71 km = 116.71 km ^2

Thus if the sun radiates energy to the value 1.3 kW/m^2 then that's 116710 metres x 1300 watts of energy over that area being 151,723,000 watts or 151,723 kilowatts. Based on a 5 hour peak sunlight window that's 758,615 kilowatt hours per day being @ 50% conversion efficiency, 379,307.5 kwh per day.

Now 151,723,000 watts / 300,000,000 = approx 0.50 watts per person with 100% conversion efficiency, so realistically the 50% conversion efficiency gives us approx 0.25 watts per each person of a 300 million population.

Then we have to consider 0.25 watts only at peak sun hours of say 5 hours per day. That's only 1.25 watt hours per day per person. Certainly no more than 2 watt hours per day allowing for lower sunlight outside of the 5 peak hours.

Now I am worried :/

On the reverse check calculations say the average person uses just a measly one kwh per day, though I'm sure the real figure is higher. The 1 kwh x 300 million = 300,000,000 kwh per day being 300 billion watt hours per day.

Now to meet this need you would need 300,000,000,000 / 379,307,500 = 790.91 x the area suggested as being required. Thus you would need 790.91 x 13,621 square km being 10772985.11 square kilometres being 3,282.22 km squared. This may provide 1 kwh per day for every man woman and child in the USA of the 300 million population.

Thus even if my own figures are not accurate and I do suggest they are somewhat conservative, I do think there has been a gross under estimation of the amount of land area required, by a magnitude of at least 790 and I suspect in reality a magnitude of over 1000. i.e you would need 1000 times as much land as they have suggested assuming they meant 92 miles x 92 miles.

Further to that you would need 60 billion watts of energy to be extracted from your 3,282.22 km squared land area, based on the 5 hours on peak sunlight to get that 300 billion watt hours or 300 Gigawatt hours per day, being 109,500 Gigawatt hours per year.

According to sources, the total U.S. electricity generation was 3,841,456 gigawatt hours during 2002. Hmm that's allot of power and it suggest even my estimates are incredibly optimistic by a factor of 35 times. Thus you would need 10772985.11 x 35.08 = 377,916,317.65 square kilometres or 19,440.06 km squared.

Now this implies a 35 x 1 kwh hour daily electricity consumption, but in reality that's the source consumption or generation. Now we loose efficiency in grid transmission which accounts for some of the lost electricity. Also much of the daily electricity used is not household usage, but rather commercial and public service usage. Thus these figures don't seem so far fetched when you factor them in also. Daily household usage is not 35 kwh per day but more like around 20 kwh per day, thus the rest is used by commercial and public facilities and as mentioned some transmission loss.

Thus no matter how you look at the figures its a huge ask, but still we absolutely have to pursue to get the numbers down.

USA 2006 electricity consmption, I suspect significantly higher again

Current generating capacity of the US is (I think) about 460 GW (equivalent to around 460 large nuke plants). Sunlight comes down with a maximum power, at noon, of about 1 kW per square meter, which means that you'd need 460 sq km (178 sq mi) of area.

BUT - and this is a big but (as Pee Wee said, everybody has a big butt, and it's always getting in the way) - that assumes 1, It's always noontime; 2, It's always sunny; 3, You get 100% of efficiency from your collectors. None of those conditions is even remotely possible. More likely, you will need at least ten times that area, probably closer to 20 times.

So now you're talking about 4000 square miles covered with solar collectors. Can you keep them all working? What about the environmental effects of sequestering sunlight from such an enormous area? And many other potential problems.

So I don't like that idea. It can help, but we will really need multiple solutions.

Nuclear is out. Too dirty. Not only the spent fuel, but the reactors and related components themselves! Did you know that a reactor's lifetime is only 20-30 years? Then what? They're too big to carry away, too radioactive to cut into pieces. All you can do with them is put up a fence and post a guard. Forever!

Solar can help, hydro can help, so can wind and tides and waves. A real biggie that no one's talking about yet is geothermal. There's plenty of heat down there. All we have to do is bring it up.

I read that the USA had over 1 terrawat of installed electricity capacity as of Dec 2006. I also read that the sun globally generates 350,000,000 terrawatts. Huge potential but huge hurdles also. Still struggle on we absolutely must. Breakthoughs will come over time.

Sorry I meant 350,000,000 terrawatt hours per year, of energy generated by the sun and hitting earth.

OO7,

Think you need to check your calcs. Your conversion from total square miles to total square meters is way off, which is why you are coming up with the wrong conclusion; i.e., that a 92 x 92 square mile parcel doesn't work. For example, one square kilometer = 1000 x 1000 = 1,000,000 square meters. But even your conversion from sq. miles to sq. kilometers is also off.

For everyone concerned about how much land this takes up, a 92 x 92 parcel represents a small fraction of what's currently used for farming in the US.

DC isn't practical for long-distance transmission

There is NO good reason to use DC over long distances

Goober is right about DC not being the appropriate choice for long distances.

Really?

Someone should probably explain that to the engineers who built the Pacific Intertie, a 3100-megawatt- capacity long-distance high-voltage DC power line that transmits power from the Pacific Northwest to Southern California.

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

I'm sure they'll be mortified when they realize how badly they've screwed up.

I am much dumber now after reading these comments.

Yeah, I can see how that could happen.

Nice article. I agree that it would be a massive mistake to think of this as a potential solution to all of our energy problems, but it is certainly a step in the right direction, and one that should be encouraged.

Hey, that was a different Paul

In response to the all the tress you'd have to clear in the desert discussion, there are things just are important in the deserts.

It takes hundreds of slow careful growth to sustain our nations deserts. They provide homes to many species of rare animals and plants. To destroy 92 square miles would be an atrocity. Just because it doesn't rain doesn't mean it's desolate. Though I don't recomend hugging cactuses, someone has to.

Nikola Tesla and Thomas Edison fought this battle a long time ago and Nikola won. AC is the one that makes sense. I think our scientists would be better utilized working on other sustainable energy projects.

I guess there is technology nowadays that allows high-voltage DC to be transformed efficiently, on a scale that utility companies can use. Which amazes me.

Thanks for teaching me about high-voltage DC.

I still stand by my earlier comment about not replacing the whole grid, and just putting in a few long-distance DC lines. Though it seems some people here on the West Coast have beaten me to that...

Ah yes, my error. I think it should have been 13,621,000 square metres x 1300 W/m^2 to get total watts hitting the earth. Thus 17707300000 watts or 17,707,300,000 17.7 Megawatts

17707300000 watts /300,000,000 = 59 watts per person

At 5 hours sunlight thats 295 watt hours per person per day. OR at 50% conversion efficiency 147 watt hours per person per day.

Still way too little by a factor of 6.8 to achive 1 kwh per person per day. But in reality way too little in terms of total electricity used by all sources, domestic, commercial an public.

Sorry I meant 17.7 Gigawatts. I give up. I will leave it to the pros. Good Luck all.

I wonder what 92 square miles of solar radiation all focussed on the same point of our atmosphere would do to the weather patterns in the US. Could it alter airflow, interrupt the westerly's? I don't have a clue, but I wish someone would at least address the possibility and assure the rest of the world that there's nothing to worry about.

While I certainly agree that there can be no single "end all" source of electricity, capturing some sun light in the desert southwest makes loads of sense to me!

I live in Iowa, and there are 31,600,000 acres (or 49,375 square miles) of land being used for farming in Iowa alone. (source http://www.iowadatacenter.org/quickfacts). Using 8,500 square miles in the desert so we can burn less coal is just a no-brainer.

Oh, and I see no reason why the 8500 sq miles would have to be contiguous. Corn & soy bean farms in Iowa are broken up, and owned by many different entities. Why couldn't different individuals or companies build their own solar farms, broken up across the desert, and sell the electricity on the free market? Think moisture farms on Tatooine (Star Wars reference for those not geeky enough to get that).

There is a lot of land east of the Cascades that would do well for this sort of project here in Washington State. By breaking it up, as "tchamp" suggested, it would allow animals to get the sun they need and also provide shade for them in the hot summer months. There would have to be some study to discover whether or not the animals would take to these being there or not. They might just like the shade. That way, the animals win and so to the people by getting energy from the sun.

You can buy a 45 watt solar roof panel right now at a well known discount supply house for about 169 dollars. If everyone in the USA bought one of these every month for 10 years (120 per person) and set it up on the roof of their house connected to the grid, you would expect to be able to generate a lot of electricity. 45 watts times 120 = 5400 watts per person per hour of sunlight. This is something you can do now with no fancy science or math. You can do it with a screwdriver, a pair of pliers and a wire stripper - oh and a check.

I don't know how to calculate this, but if solar energy were to be converted efficiently into electricity and then sent north, would that lower ambient temps at the plant's location at all? Many cities all across the south have been hitting temp records this year. I think that a solar panels on rooftops and over parking lots might provide enough shade to reduce insolation and therefore cooling needs. Maybe future cities on Earth will be domed to provide electricity as well as UV protection.

See if you can find the Lowest Price for Solar Power in SmartShopper.
http://www.smartshopper.com/tags/Lowest_Price.aspx

There could be potential micro climatic effects, but I doubt anything major. The same amount of energy is coming down, its just that its being obstructed from hitting the earth directly. Now if this means that its re-radiated back to the atmosphere more rapidly then depending on its scale there may be micro climate implications. The scale would have to be huge though.

DC is much more efficient at high voltages, because AC suffers from the skin effect http://en.wikipedia.org/wiki/Skin_effect
The reason why AC is in such common use is because of how difficult it is to increase the voltage of the DC current without the use of a transformer. Also DC is safer

I'm gonna hate myself for doing this.

First off, according to

http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6V50-3YMF6NM-4&_user=4421&_coverDate=03/03/2000&_rdoc=1&_fmt=&_orig=search&_sort=d&view=c&_acct=C000059598&_version=1&_urlVersion=0&_userid=4421&md5=ed8d8028f31932bb1be5682034d571b9

The incident energy that's useful is around 900 w/m^2, and varies as a function of season. More importantly, they go to great lengths to talk about how efficient their Fresnel lens arrays are. Their calculations were on the order of 6 MJ/(m^2*day). This corresponds (DOES NOT COME FROM, BUT IS THE EQUIVALENT OF. Please understand) to about 30% efficiency for a 6 hour day. e.g. (1m^2) * (900 W/m^2) * (6 hr * 3600 s/hr) * 30% = 5.83 MJ.

Secondly it's almost certain they mean 92 miles square. Google tells me that's 2.19216594 × 10^10 square meters. Go google.

Finally, we take that area, and multiply by the theoretical yield per unit area. (2.19 × 10^10 m^2) × (6 MJ/(m^2 * day)) = 1.3 × 10^17 J/day.

I think this rough estimate is ok, but feel free to improve on it.

Finally, we need to put this in everyday terms to see what it says. A kilowatt × hour is 3.6 × 10^6 J. Thus 1.3 × 10^17 J corresponds to 3.61 × 10^10 kilowatt*hrs. That's 36 billion kilowatt hours produced in a day. Another every day term for that is, 120 kW*hr per person in the US each day.

Read that paper, there are obviously more considerations (the paper was written for Australia, for example), but as a rough estimate this suggests his idea to be feasible.

uh, fix this web page layout. the right column (are you an eco geek?) is blocking the entire story!

The small 2' by 3' solar roof panels now available that produce 45 watts of 12 volt electricity that cost less than $200 each could make an appreciable dent in our power needs if they were placed on our roofs. Everyone lives under a roof of some kind or works in a building with a roof. The sunshine that falls on all the roofs in the USA is a huge amount and it currently does nothing for us except degrade our roofing material. There is no need to use up big square areas of land and use transmission lines to power the grid. The system would start producing power for the grid at sunup on the east coat until sunset on the west coast. The cool thing about this is YOU can do it NOW. Learn about it and plan to spend a couple of hundred dollars per month and you will be able to make a difference. Doing it a little at a time will allow the power companies time to adjust to making power only at night and we will learn to conserve electricity by using it mostly in the daylight hours. None of this is rocket science, it just requires each of us to make an investment in our future. If people start buying lots of these solar power panels the companies that make them will figure out how to make them better and cheaper. The power companies are required now to buy back the extra power you might produce as long as it is ac and the right frequency which you can do with a simple inverter. Some people are using these little solar power plants to get off the grid but the real answer is to put millions of them on the grid.

Yeah, my mistake, I put the link in there and apparently this page doesn't enforce word wrap. Wow.......

Temperatures across the American south have been at or near record levels recently. Perhaps it's time to start shading our homes and parking lots with solar panels. I don't know how to calculate it, but I'm sure that energy (cooling) costs would be lower if less sunlight were actually reaching the surface. Also, it is my understanding that photovoltaics are more efficient when cooler than the average rooftop. If that's the case, then why aren't those panels backed by a heat exchanger that could at least preheat a residential tank. Industrial sized units could be used for process heat or even low pressure desalinization.

120 kW*hr per person in the US each day ? 120 kwh ? That does not seem to make sense. The average household uses about 20 kwh per day. Say that's shared by 3 people per household then that's a usage of about 6.6 kwh per day per person. Add 20% transmission loss and that goes up to 8 kwh per day per person for domestic use only. Add that again that for commercial and then again for public transport. Thus I think at worst the average person would consume not more that 24 kwh per day and suspect this is a significant exaggeration.

Your calcs may be OK but there are efficiency losses and one is looking at source potential availability against processed output of energy and efficiency losses at various stages. I think deciding how to represent this in terms of usable electricity to the end user for given land area covered, is the slightly more tricky part.

92 miles squared = 92mx92m = 8464 sq miles or 13,621 sq kilometres, but again I'm still finding it hard to see that generating enough power for 300 million people, given the efficiency losses in conversion from sun to power and transmission losses.

At 1300 watts/m^2 Im getting 59 watts per person available at source before any efficiency losses. Even on a 6 hour day this falls well short of 120 kwh per day per person.

Yes the web master needs to fix this web page layout.

I'm not saying solar power isn't a great alternative, but nuclear power is clean and efficient I don't know where you got that 20-30 year life span I would like to see some stats on that.

i just found out about Pure Energy Solar. these guys do really great work installing home solar energy systems. they are super cool guys and have a lot of great information on their website, pureenergysolar.net. if you are looking for someone to put together a solar electric system for you, or just need them to answer your questions, give them a call 1-352-377-6527. 8)

92 x 92 miles delivers all US megawatt-hours -- day and night. Thermal energy storage is built in. Read the introduction on the Ausra web site.

DC transmission avoids inductive losses and is more efficient for long haul. That's why it's used today to bring hydro power from Oregon to LA, and to bring coal power from Utah to LA.
DC transmission also allows different regions of the country, which are separate AC 'sync' areas, to be tied together.

92 * 92 mi = 8464 sq mi
1 sq mi = 2.58 sq km
= 21837 sq km
1 sq km = 1,000,000 sq meters
= 7279 watts/person at 300m people. Surface (not space) irradiance is 1000 w/m^2

I just want to throw more light on this issue.

Nuclear cannot be considered clean because it produces radio active and highly toxic depleted uranium waste.

Nuclear also cannot provide the idealistic energy independence because uranium supplies are mostly from outside countries like Russia.

Nuclear production is very expensive and probably most expensive if not because of heavy subsidies.

Nuclear waste buildup is another big problem. Abandoned waste can be used and stolen for wrong purposes.

In short, nuclear power pales in comparison with Solar, Wind or GeoThermal in terms of potential drawbacks and long term benefits.

See http://www.commondreams.org/views05/0415-23.htm if you are interested in a much better write up.

yeah reading the article is much better than reading the opinions of some people who probably never passed high school... DC lines would be perfect because as it has been stated many times before this, WE ALREADY USE THEM FOR LONG DISTANCE HIGH VOLTAGE! secondly to all of you that are trying to calculate the area of land needed to make this possible, true while it doesnt need to be one big square section of land, most of you are using a 100% conversion of the energy from LIGHT (something we are far from even becoming efficient of at 50%) when the article says we'll be using mirrors to use the HEAT energy to heat oil in a tube to extremely high temps, obviously well above 212F to instantly turn water to steam which powers turbines... which im sure the steam will be cooled and condensed back into water to be heated again and again and again... or could be used to heat the oils for a portion of the night to provide more energy from the same system... also people who calculated 6 hours of peak sunlight, try waking up earlier and going outside... there is still plenty of daytime to use heat from the sun to heat the oils up... but the peak ours could produce more electricity than the whole of the beginning and end of each day... so calculate all of that extra energy and then start coming up with some figures... as for electricity at night... it may not power all night but that oil isnt just going to drop its temperature like a rock, we'll still get some production out of it... especially if you use steam to keep the oils at temps above 212F... im no scientist, but its obvious that some of you arent taking all the calculations into effect... something im sure the ausra company has done since im sure that they would be scientists... but thats just be using basic logic and a bachelors degree in liberal studies... as for the alternative of using solar panels on every roof and having them plugged into the grid to gain energy from east coast to west coast is probably the simpler and faster choice of improving our country's energy usage now... just have to get law makers to help enforce every house and building to install solar panels... both ideas will take time, yet both are good... and if we use both ideas tapped in with wind and wave power... we'll be using nothing but clean energy... nuclear is also stupid for the long run... not to mention if anything went wrong it would be a disaster...

I see migration towards the power-source and a re-building of old technologies that waste power, by newer better designs! I see huge, underground civilizations in the American deserts, interconnected by tunnels with electric conveyances, supporting the Solar Power on the surfaces, and living in the cool soil beneath! I see whole factories, commerce, complete with Malls, all sky-lighted, and even gardens, growing hydroponically from radiated sewage, for food!providing deserts with life-giving fertilizing sludges! I see a gasoline free, nuclear free, way of life! I see a skin-cancer free generation, hidden from the ravages of this planet in the ultimate "Earth-Ship" home, beneath the solar collectors, and the hot sands of the desert, and providing power for all!