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I live in MN. We get more sunlight than Florida.

I'll assume you mean more sunny days, but more sunny days != more useable sunlight. This is for a variety of factors, but mostly it comes down to your latitude, which means the sun has to go through more atmosphere at an angle to reach you than it would closer to the equator. Even with more cloudy days, FL gets about 25%-30% more solar energy than MN in an average year, which follows conventional wisdom.

http://www.solar4power.com/map2-global-solar-power.html
http://www.solar4power.com/map3-global-solar-power.html

I live in MN. We get more sunlight than Florida.

I'll assume you mean more sunny days, but more sunny days != more useable sunlight. This is for a variety of factors, but mostly it comes down to your latitude, which means the sun has to go through more atmosphere at an angle to reach you than it would closer to the equator. Even with more cloudy days, FL gets about 25%-30% more solar energy than MN in an average year, which follows conventional wisdom.

http://www.solar4power.com/map2-global-solar-power.html
http://www.solar4power.com/map3-global-solar-power.html

1. At that latitude, the angle you mount your panels for operation would be steep enough for most snow to slide off. Also the dark color of the panels means that the snow will melt off there first. Although the snow may eventually build up at the base and block the rest from sliding off.

2. Amount of Sun. It's all about the solar insolation measurement. The feds have been logging this data for 30+ years and averaged the amount of annual sunlight in several areas in each state.

http://www.solar4power.com/solar-power-insolation-window.html

The above link is a good chart for this. The average for cities in New York is about 3.5, which equates to right around 3.5 kWh daily output for each installed 1,000 watts of generation capacity. That isn't the best, but it still is plenty. Germany has the largest number of installed PV arrays, and they are just as, is not more cloudy than New York.

I operate a 10 kw solar PV array in perpetually cloudly Seattle. We're going to see a payback of right around 10 years. Solar works just fine for us, although we do expect greatly reduced output in the winter months. The longer days during the summer, due to the high latitude, helps make up for some of that though.

http://www.jbdg.com/solar.html My array.

At 40%, you're talking about 400W when in direct sunlight. With eight hours of sunlight per day the average house needs less than four square metres. Now, of course, you aren't going to be using the most power at the times when these are generating, but it can definitely put a significant dent in your electricity bills.

Your math reads, to me: 400W * 4 * 8 hours * 365 days = 4,672kWh/yr

Unfortunately, both the 8 hours per day and the average usage per year are incorrect.

Average electricity use in 2001 was 11,965kWh/yr [ US EPA ]. Average solar power insolation in the US is around 4.8kWh/day [ Solar Insolation for U.S. Major Cities ] (caveat: I took the average of the listed cities averages, so it'll be skewed towards more populous regions in the US)

Therefore, 11965/(365*4.8*400 = 17m^2 of this material, just to generate enough energy over the course of the year to net zero over the power company's input. If you want to be grid free, you need to size for the worst case (winter), which is 3.75kWh/day, or 22m^2. That does sound like a lot, but then again, 22m^2, is only about 5m by 5m (15ft x 15ft). Even a single story 1000 square foot home has at least twice that on each side of its roof.

I'll note, though, that this average probably includes air conditioning and electric heat, which are huge energy sinks. But then again, if they're what people want, then they'll need to be able to support them in their system.

It doesn't make sense to put a solar panel in a place that doesn't get a lot of sun, which, relatively speaking, is most of the world. I'm not sure that a lot of thought has gone into putting solar panels at sea, if you look at a map, like this one, they don't seem to care about the ocean. It would seem that the air over the ocean would be more humid, in general, than air over land, and thus worse for solar collection. I agree with your basic premise - there are lots of places where it would be a lot easier to place solar panels than the sea. Buildings in the desert, or power lines crossing the desert immediately come to mind.

To calculate cost-making sense we need to know the following: The price per instant energy production and the length of time energy will be produced. You first call into question the $1 per watt value, and I that is the cost to produce. I'd expect the retail cost to be 2-3 times that as you show, so let's say $3 per watt of maximum capacity. Now how many hours will we be sunlit? Thankfully someone put out a chart for us displaying low, high, and average Sun Hours / day so we don't have to calculate based on weather data and seasons. Let's use someplace close to me, Ames, IA, with a relatively low 4.4 sun hours / day. With a $3,000 investment, that would get us 4.4 kwh/day. The typical life of most solar cells is around 20 years, so that turns out to be 32,120 kwh for a $3,000 investment, or around 9.3 cents per kilowatt hour. Pretty close to your calculations. However, this may make more sense for someone living in Las Vegas. With 6.41 average sunlit hours per day, that brings the total to 46,800 kwh over the usable life of the product, or 6.4 cents per kwh. So the price per kwh produced could be anywhere from 2.1 cents ($1 production price per watt with zero markup in Las Vegas) to 9.3 cents (200% markup and in Iowa). I currently pay 8.2 cents per kwh, so the break-even point for me would be if I could get a working unit installed for $2.60 per watt. In Las Vegas, the break-even point would be at $3.80 per watt (if their electricity costs the same as mine).

Now the real issue. Suppose everyone does this. It will have the effect of destabilizing the grid because it puts the power company in the position of standing by ready to supply energy at night and when the sun doesn't shine but meanwhile when the sun is shinning their expensive infrastructure sits idle. So long before this gets deployed the rules get rewritten.

Peak energy usage hours are usually in the daytime, and when it is sunny. The main reason I believe is air conditioning and because people are at work. This could actually help to stabilize energy usage so the power companies' equipment that struggles to meet demand in the daytime isn't sitting idle at night anymore. The electric company would have instant additional unused capacity without making a capital investment and a more constant demand for energy.

The number you quote seems to be closer to the extraterrestial solar flux of between 1.3 and 1.4 kW/square meter.
http://www.pages.drexel.edu/~brooksdr/DRB_web_page/papers/UsingTheSun/using.htm/
According to ASHRAE, a horizontal surface on the earth will get around 256 btuh/sq ft peak at noon on a clear, sunny day. By my calcs, that's about 800 Watts/sq meter.
For yesterday's data on actual insolation at the surface in the Western US, see this:
http://www.soils.wisc.edu/wimnext/insol/westinsol.html/
Here's a little more on the subject:
http://www.solar4power.com/solar-power-insolation-window.html/
http://rredc.nrel.gov/solar/old_data/nsrdb/redbook/atlas//

Take a look at this map:

http://www.solar4power.com/map2-global-solar-power .html

You don't provide any sources for your information, so I have to assume it's just out of date. PV's have become significantly more efficient in recent years, and there are tax incentives and utility subsidies for commercial ventures installing solar, not just residentials. See the following for more optimistic (and current) information on solar in commercial settings:

-solarelectricalsystems.com
-solarelectricpower.org
-solar4power.com
-borregosolar.com
-Akeena.net

Those were just the first few relevant hits on Google. I'm sure spending more than 30 seconds researching would yield better quality results, but I think those are good enough for now.

A house with these panels can provide most of its energy, and on sunny days even feed excess back into the grid (electric company pays YOU)

And as you can imagine, the electric companies hate this. They oppose it everywhere they find out about it. Usually they claim it's on technical grounds (i.e. the installation isn't done properly, the equipment will cause massive blackouts, etc.) which are usually complete BS. Some installations might, but if it's done right, then it will work perfectly.

Considering the enery crisis, and terror threats to centralized power, it would seem irresponsible NOT to try and push for distributed solar power generation. It makes sense in almost every way (money, eco-friendly, security)

Unfortunately, solar panels aren't quite yet cost-effective enough to replace electricity, but they're getting closer and closer. Further research in this area could only help. If I were unfortunate enough to be stuck living in California, I would insist on having a solar-powered home, even if I had to build it myself. There are just way too many blackouts, brownouts and shortages there...

Nuclear power is NOT clean, safe, or cheap. These illusions are carefully crafted and maintained by the nuclear power industry and the Department of Energy.

Nuclear power plants seem clean because there aren't any smokestacks billowing pollution into the air, but the polution they produce is invisible to the human eye. Why do you think nuclear power plants can't be built near populated areas? Additionally, the process of mining the fuel is exremely poluting, and there is no way to dispose of the spent fuel rods, which are still extremely radioactive. Currently they are generally stored in on-site storage tanks awaiting the day that the government sets up a central storage area and takes over the responsibility. This brings us to safety.

Nuclear power plants could be safe if they were properly maintained, but of course they aren't. Why? Because maintainance costs money, and power generation costs money. The corporations that own these power plants would rather buy DOE officials than properly maintain the deisel generators which provide backup power for the cooling system. In fact, the lack of mainainance at nuclear power plants was one of the few valid y2k fears. Nuclear power plants are required to power their cooling systems (which are the only thing preventing meltdown) from the grid. In the event of grid failure there are the afor mentioned backup generators. Unfortunately there is sufficient evidence for concern that even the redundant backup systems would fail. Chernobyl and Three Mile Island provide very convincing examples of what happens when systems fail at a nuclear power plant. So much for safety, what about how cheap it is?

Guess what? It isn't! Nuclear power plants are subsidized by the Departments of Energy and Defence. Since this cost is hidden from the consumer, nuclear power appears cheap. Our tax dollars at work!

Of course, I don't expect you to take my word for it. Feel free to verify anything I've said hear. This link should get you started.

I don't want it to seem like I have something against nuclear scientists, I know a few and they are very smart people. I would feel a lot more comfortable with nuclear power if the engineers and physicists were actually in control of it. As it is, politicians lie for a living and any confidence I may have had in business folks was squelched in my days as a math tutor. I've seen the kind of people that major in business, and I wouldn't trust most of them to run my coffee machine.

It would be awfully inflamatory of me to shoot down your solution without presenting one of my own, so here you go. I won't argue that deregulation has caused a lot of problems, but it also encompasses the solution. Thanks to deregulation anyone can produce power and feed it back into the grid. For a few thousand dollars you can buy a few solar panels and a phase matching inverter. Wind generators and micro-hydroelectric generators can also be had fairly cheap. Last time I went to San Jose I saw lots of sun and wind not being used. If all these companies that are suffering under the yolk of rolling blackouts put up roughly one of thier CEOs weekly salaries for equipment and installation, the problem would be solved. If Reagan hadn't done away with the tax credits for doing so, they probably would.

Again, I encourage you to check it out for yourself. Try this link for starters.