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We are living in curios times, when the World is facing immense global challenges, due to global warming [1], and the solutions have to be addressed collectively, from the global scale down to that of a household. Many of the solutions are within reach, but still need to mature. Many people do not understand the problem, of global warming, or deny its existence. In this environment one may find oneself debating with people who totally disagree with you, or with people who have the same goals, but strongly different views on how to achieve them [2]. In the first case you will have to spend a lot of time explaining the problem, and in many cases this may be a futile effort. In the latter case the disagreement's are more solvable because they  are usually based on differences in opinion on what solutions are feasible now, and what may have potential in the future. 

Nuclear energy has been around for over 50 years, and is a proven source of reliable power generation, that does not release greenhouse gases (GHG). However, it requires a very large up front cost, as well as a long time to build [3]. After the plant is built the costs continue [4], with the need to store the radioactive waste, and eventually shut the plant down [5]. Then there is always the small chance that there will be a nuclear melt down, which can leave large areas uninhabitable. All of these things makes nuclear energy a highly specialized form of energy generation, practiced by a relatively small number of organizations. This in turn makes it difficult for nuclear energy to evolve. People are not playing with nuclear reactors in their garage, or at least lets hope not. There are efforts to make small nuclear reactors that are more accessible [6], but they have many hurtles before becoming as accessible as solar photo-voltaic (PV), or just an ordinary petrol power generator. However, because of global warming there is still a strong incentive to make nuclear safer, cleaner and more cost effective, so someday it may make a comeback. The holly grail in this challenge would be nuclear fusion [7], which would indeed be an energy revolution! 

Solar PV, on the other hand, is a very accessible source of energy generation, but does not have as long a proven track record of supplying reliable power, as nuclear energy. The price of solar PV, has dropped by 75 percent since 2009 [8], and it is expected to drop another 40 percent in the next two years [9]. Along with government subsidies, this has resulted in a dramatic increase in solar PV installations. One thing that makes solar popular, other than its cost and that it does not produce GHG, is how distributed it can be. The largest solar PV farm is Solar Star, in California, which has installed capacity of 579 MW [10], but then solar PV is just as capable of being installed on your roof top or watch. Currently solar PV is something that is visibly recognizable, but that will change with solar windows [11], and solar paint [12] making it ubiquitous. These characteristics makes the development of solar more like the internet with its start-ups, disruptive culture, and connectivity everywhere than traditional power utilities and generation technology. 

Like many other forms of renewable energy, such as wind turbines, solar has an intermittence problem. Obviously, when the Sun is not shining it is not working. In someways solar is more predictable than wind, in that we can easily calculate when the Sun will rise and set, but then you have to predict cloud cover, which can be even more difficult than predicting wind speed. In both cases improved weather forecasting is making renewable energy more competitive, requiring less back up power from conventional fossil fuel burning plants [13]. In areas where energy use is high during mid-day hours, such as in the sunbelt where air conditioning use is high, solar can be an ideal source of energy. 

However, with increased development two problems can arise, the duckback curve and value deflation. The duckback curve occurs when you have enough solar energy, especially from roof top solar, in the day to turn what was a peak period of energy demand, into a valley. This is a good problem in a sense that it would show that solar is capable of really putting a dent in the need to use fossil fuel energy generation. The problem occurs latter in the day, when there is another energy use peak as lights are turned on as the Sun sets. Of course since the Sun has set solar energy is no longer available, and conventional fossil fuel burning power generators have to ramp up quickly to fill the gap. This is not easy to do [14]. Solar's potential of turning the mid-day peak of energy use into a valley also suppresses the cost of electricity during those hours, leading to what is called value deflation [14]. This can increase the time it takes to pay off investment in solar PV. It is most acute in cases in which solar energy is being sold on the electric power market, such as with utility scale solar. In the case of net metering these issues have been used by utility commissions to change net metering agreements, reducing the price utilities have to pay for energy from rooftop solar [16]. This reduces the time required for the owner's or rooftop solar to pay off their solar panels, but depending on where they live they still will save money supplying their own power [17].

This brings up the question of what is feasible now, and what will be possible in the future. If you look at things relative to cost, than solar PV is still struggling to be competitive with fossil fuel, all though it does appear that it is a mater of time before the issue of cost becomes irrelevant. Then there is the problem of intermittence, which has lead to an increase interest in electrical storage, setting up a new cost curve as solutions for it are developed [18]. This is setting up a reverse paradox in which confronting global warming was portrayed, by the Bush administration, as being costly to the US economy [19], but the solutions are turning out to revolutionize society, not just solve global warming.