My biggest question about what will happen if we had 20% or more of solar/wind power is what do you do when the wind isn't blowing and it is night time? You are still going to need as much traditional generating power as we have now but it will have to sit idle while the "free" stuff is working but be ready to fire up at a moment's notice when a big cloud comes over or when the wind dies down.
That is the sad truth about alternative energy. They all have their limitation. Currnetly at best with the national grid system (despite it's current condition), alternative energy systems only supplement the grid. It helps but does not fix the proplem. Solar does work on cloudy days but not as good on a sunny day. Currently the best all around alternative energy source is is hydro it the areas can support it since it can be operated 24/7, in the dark and with no wind. There are limitations as well. Althouygh they can pay for themselves, they are very expensive and a pistol to get built. He in Southeast Alaska, Most people get their power from hydro. The problem is most of SE Alaska is protected by environmentalists. Currently two of our largest communites are up against the wall because their generation capacity has been outpaced by growth. To add to the problem, fuel cost has sky rocketed. This pushed utility rates and construction. The hydro system I am on has an abundent surplus of power. everyone wants to tap into it but it cost miillons of dollars and lines need to cross disputed and protected lands. With todays fuel costs, more and more people here are going to electric heat. The reservoirs are slowly dropping already. Although we have the capcacity now, the suplus will keep getting chipped away where we will be in the same boat eventually. The only upside is anyone who taps into our system can be cut off if the demand exceeds the capacity.
Now that I am on a roll and off the topic of the original post (sorry), here is some food for thought. Our planet recieves 5000 times more energy from the sun then we use daily. I ran some numbers. In theory if each person on the planet had a solar array that is 125 square foot array or ten, 125 watt panels per person and they were all interconnected around the world, we would be able to shut off every single power plant in the world and be powered by totally by the sun.
