If there is one source of energy that every single person in the world has access to on a daily basis, it is solar energy. While solar energy is not used in any part of the world as a primary source of energy, changing global trends are pointing in the direction of renewable sources of energy. Almost everywhere in the world, the most commonly used sources of energy are crude oil, coal, natural gas, biomass, nuclear power and hydroelectric power, in that order. Renewable energy is used in such insignificant quantities, that it does not even feature on the list. There solar panel cost are many reasons for this. The first and foremost reason is attributed to the industrial revolution. When the power of fossil fuels was realised, the world became so dependent on it that little research was done to find alternate sources of energy. Back then, nobody anticipated that a time would come when there would be a global shortage of fossil fuels, or that one day, fossil fuels would get depleted altogether. As a result, renewable sources of energy went largely ignored. As a result, today, the methods we employ to harness solar energy, tidal energy or wind energy are so poorly developed, that in terms of efficiency and cost, there are more reasons to not use these sources to generate electricity than to use them. Solar panels have very low efficiencies, meaning that single commercial solar panels can generate only very small amounts of electricity; so less that the amount of electricity generated will not be sufficient to power even a single household. To meet the requirements of the average household, a large number of commercial solar panels or commercial solar panels with a very large surface area will be required. When it comes to windmills, people find them to be an eyesore, and complain about the noise made by the blades as they turn in the wind.