I haven't heard much from nanosolar for a while.

Has anyone heard what projects they are up to at the moment?

The last I heard they were doing utility scale projects. It seems that they need reliability data to move forward with commercial products. Not many people want to buy solar panels if they die in a few years, so they have to show that they last. Plus, they really don't have a distribution network and do not want to spend the money to create one right now.

It will sound strange at first, but it can be shown that all energy used by humans is given by nature free to humans and all other life. Solar obviously yes, but oil most, if not all of it, is just solar captured by ancient life. This is more certainly true with coal. Wind is just a more immediate version of solar energy, and hydro-power is solar more delayed. Uranium is the remnant of long disappeared suns.

There may be massive amounts of metalic uranium in the metal core of the earth, since uranium is twice as heavy as iron. It is thought that the heat within the earth is generated, at least partially by the transformation of uranium and thorium into lead. There are the known natural fission reactors of OKLO ore bodies and there may have been or may still be chain fission reactions going on in the depths of the earth. Geothermal energy is thus, at least partially, uranium or thorium energy.

The depletion of the amount of U235 over millions of years of natural transformation prevents any natural uranium ore chain reactions at this point of history. The magic of isotope concentration and carbon and heavy water moderation allows modern nuclear reactors.

The only cost issue is how much material-costs and effort-costs it takes man to collect and use the energy. If the release of Carbon Dioxide from coal, oil or gas becomes intolerable to present human society it means that the costs of coal, oil and gas use are infinite. In this case nuclear fission reactors are cheapest source of electricity. They are also the cheapest source with oil at more than $30. They are much cheaper than solar cells.

Solar electricity with energy storage or substitute generation and remote collection, needs the costs of generation, transportation and storage added to the already high costs.

Low interest loans can make nuclear reactors much cheaper. CANDU reactors can have all of their parts repaired or replaced every twenty or thirty years. The heavy water is a major cost of such reactors, but very little is destroyed during operation and the remainder is purified and can last forever. It can also be a source of tritium for fusion reactors and emergency lighting.

The cost of uranium is a very small part of a power bill, and the total life amount of radio-active materials from a nuclear reactor that have to be stored with adequate safety is less than the size of a large house.

If all electricity in the US were produced from uranium, and if the total amount of US electricity produced was divided by the number of residents, each residents proportionate amount of materials needed to be stored after a lifetime of use would fill less than a cup. This is also the amount of uranium needed for his direct electric personal use and his divided share of all electricity used in the country during his life.

The amount of carbon dioxide released in this situation for and by this person for electricity would not be equal to a few candles and far less than a single tank of gasoline.

There is actualy not enough land area for the amount of solar energy we may want to use in the future.

Nuclear energy may not be renewable according to most peoples definition, but there is enough uranium and thorium and other heavy metals for millions if not billions of years and by then fusion reactors will only be 20 years in the future. ..HG..

I am very reluctantly coming around to agreeing with Henry. The melt-down issue has been solved with CANDU. However, all advocates of nuclear power always gloss over the issue of waste disposal. There still is no solution. Most nuclear waste is sitting in drums stacked up (dangerously) near the reactor that produced it.
This has been my main objection.
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But i have come around to seeing that nuclear waste sitting dangerously behind some barbed wire is still better than releasing the CO2 from coal. You can't put barbed wire around the CO2...it's released and cannot be retrieved. At least you can build a better fence around the nuke waste.
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My final objection has always been the rediculous cost over-runs of nukes. They have gone insanely over budget and the costs are just passed onto you and me (the power companies never eat it).
This issue has now (theoretically) been solved by mini-reactors that use a standardized plan and can be scaled up by adding more units.
If we can settle upon one standard solution the costs can be contained and the reality of cheap nuke power might finally be achieved (it certainly hasn't so far).
Now, if we can get beyond NIMBY mentality and get yukka mtn moving, we might solve the waste issue.

...ok, fire away at me!

Oops, forgot to mention that if someone can convince me that there are enough photons reaching the U.S. to provide enough power, i would not be interested in nuclear. Also, there is no current method to store electricity for night/foul weather times.
I love solar and want it to keep growing but it seems we still need a baseline source. Especially if we're going to go with EV's that need to be charged at night.

Would someone please tell me, both for currently available solar cells and for higher efficiency cells, 1) how many watts can be generated from a square meter of surface area? 2) how much it costs to purchase this square meter? Thanks

There are about 1000 watts per square meter. It would cost you about $600 for a square meter of solar panel that would generate around 120 watts.

IMO utilities are going to adopt solar concentration designs rather than PV.

SC allows electricity to be generated at night from heat stored during the day.

We all know that PV can charge batteries for use at night. Or use flywheels or several other schemes. Maybe one will work out. To me most look too expensive.

My newspaper today said Arizona Public Service, the main power utility for Phoenix, has selected solar concentration for a huge new plant on three square miles. Alternative energy wasn't mandated although that was a consideration.

Nuclear was too slow and political, coal and gas have no cost advantage with the coming CO2 regulations, and PV was expensive and also has the storage problem.

Those interested can read this:
http://www.azcentral.com/arizonarepublic/news/articles/2009/05/22/20090522biz-apssolar0522.html

Your too late.

By the time people realize solar, wind, geothermal and wave are not enough
and think we might need nuclear power
and the politicians catch on
and the green barriers are dismantled
and the insignificant waste problem is put away
and a workable approval process is in place
we will be poor and under water because we had
no power and so
no industry and so
no clout to stop China and India (and ourselves) from turning coal into CO2.

Convert coal power plants to renewable methane combined cycle power plants. While you are at it, use the excess heat for processing biofuels. This, along with wind, solar, geothermal and other sources will provide what we need when combined with energy conservation measures. There is NO problem here that can not be solved. It is all the talk and no action that is hurting the situation.

When you see how much work it took to get a 0.7% improvement in efficiency, you could see that it might be easier to work on the demand side, by switching off a few lights, or switching them to CFLs.

Henry, et al, I am with you on the Nukes, but it is a hearts and minds problem - most politicians are too scared of the anti-nuclear lobby, and the pro-nuclear lobby hasn't really got off the ground.

There are lots of building that can be made more efficient. Just taking an infrared video of any neighborhood on a cold night will show you that. Builders have not built with efficiency and conservation in mind. The air conditioners and heating systems are not the most efficient, so I do not know where the .7% comes from.

Thank you, SJC for your May 22 9:14 pm answer. I am still confused. Is the 1 kW per square meter the theoretical maximum power, and the 120 watts a typical 12% efficiency? Does the 23% efficiency that Sanyo claims result in 230 watts per meter? Thanks.

The 1000 watts is what comes from the sun to the surface of the earth. Cells are about 14% efficient, but by the time they get packaged into a panel with all the EVA covering, they put out about 12%.

Solar cells only convert a small band of light to electricity. That is why multiple layer concentrated types like those made by Spectralab have almost 40% efficiency. Just go on a search engine like google.com and enter "solar cells" and you will get lots of stuff to read.

citizen,

I think it is better to look at annual production.

1 m2 of Sanyo HIT solar cells @ 23% will have a rating of 230 Wp (Watt peak). In a sunny location and an ideal, (fixed) orientation that could produce 2 kWh/Wp/year. So that 1 m2 of Sanyo's would give you 460 kWh/year.

Divide by two for less sunny locations, like Britain or Germany. Hope that helps. More in-depth information should not be hard to find using Google.

Henry & others,

I am not too sure about the CANDU. See the sad story of Bruce A units 1 & 2. They went into service in 1977 and were stopped less than 20 years later, meaning they have been standing still for almost half of their lives. They are now being refurbished, and should be ready this year. Lets see if they make it. In the mean time, the notorious cost overruns have started to rear their heads: http://www.thestar.com/article/415772

I have no faith in nuclear energy, because imo it is always their 'next design' that is going to fulfill the promise of cheap, safe, plentiful energy. It seems each new nuclear station is a sort of science project. Will it ever become routine?

Henry, do you have a reference that there is enough uranium for millions of years? I thought there was much, much less, say 100 years or so.

"According to the NEA, identified uranium resources total 5.5 million metric tons, and an additional 10.5 million metric tons remain undiscovered—a roughly 230-year supply at today's consumption rate in total."

http://www.scientificamerican.com/article.cfm?id=how-long-will-global-uranium-deposits-last

I was just curious.

thanks SJC.

The important words are: "at today's consumption rate"

A massive shift towards nuclear would increase uranium consumption by at least a factor of 6, reducing the supply to a measly 40 years.

thanks SJC.

The important words are: "at today's consumption rate"

A massive shift towards nuclear would increase uranium consumption by at least a factor of 6, reducing the supply to a measly 40 years.

Oh yeah, there are always conditions to assumptions.
If you define every source possible you might get:

Very high-grade ore (Canada) - 20% U 200,000 ppm U
High-grade ore - 2% U, 20,000 ppm U
Low-grade ore - 0.1% U, 1,000 ppm U
Very low-grade ore* (Namibia) - 0.01% U 100 ppm U
Granite 4-5 ppm U
Sedimentary rock 2 ppm U
Earth's continental crust (av) 2.8 ppm U
Seawater 0.003 ppm U

http://www.world-nuclear.org/info/inf75.html

That would mean that if it were cost effective enough, you could mine the sea for uranium and the figure goes farther out in time, but that does not seem very realistic.