There are a couple of big pieces missing here before one can conclude that even the current energy requirements of the world or the Eastern Seaboard of the US can be affordably met by solar power. One piece is how many EJs the world or the Eastern Seaboard uses per year. Another piece is how much sunlight reaches any given region so as to make solar power affordable as the source of electricity production. It would presumably not be affordable to harvest sunlight in the Sahara Desert and transmit electricity to New York City.
And then there is just the big piece of information about how much of the surface of any given region can be covered with solar panels. After all, sunlight has to reach the surface of the earth in order to grow plants, have animals, have living oceans, etc., etc.
Right?
Yes there are some missing numbers. I don't know what the east coast power requirements are. I think that there is more than enough sunlight given that the Earth receives so much of it. Cost and power storage are the next most important questions, but first we'd need an estimate of the power requirements. We'd have to start by knowing how much power is required in the area of interest. Then we could ask a meteorologist (which I am not) how much light energy is available day and night over that area. The meteorologist could provide an average value historically for day and night time, and then based upon that we'd assume storing part of that power, probably make several estimates versus cost of storage. Then (like in the example I provide below) we could multiply the efficiency of solar panels using some conservative value (whichever panels are most efficient per dollar, say the ones that convert 19% of the light). That would give us the needed amount of panel area. So for example if we need 1 amp-hour per day with panels with efficiency of 19% and sunlight providing say 2 amp hour per square mile we'd start from our requirement of 1 amp-hour daily and calculate the panel surface area needed. Somebody would have to provide the land or else modify their property, and there would be costs associated.
Here is an example of a cheap and dirty calculation based upon a power need of 1 amp hour:
1 amp hour needed = X square miles of panels * 0.19 efficiency * 2 amp hour / square miles. Then we find X, and X is the number of square miles of panels required to achieve 1 amp hour per day given these fictional numbers. Of course you are going to check with multiple kinds of solar panels, and you are going to also compare their prices. Your spreadsheet will have many columns before the end. You will use iterations to resolve down to the best cost.
Going by the comments I have scrubbed from those sites the entire world could be powered by a solar panel the size of Spain -- but I am not suggesting such a thing. Everybody likes Spain, so lets not cover it.
Its a bit nebulous information but close enough to establish that we could power the East Coast using solar panels and that it would be a question of money and land. Whose land? Whose money?
To make a really good estimate requires input from meteorologists who should be able to estimate the light available per year, and secondly you have to use a spread sheet that lets you put in different brands and types of solar panels. That way you can look at all the possible values. A more efficient panel could either make it so that you need fewer panels or so that you can have more energy in the same area of land. These are choices which make the estimation more complicated. A third complication is that now there are flexible solar panels, so these can be put into more situations. Since they are not yet in common production there is nobody we can ask about them except the research teams which currently are working to get patents on them.
