|Fig. 1: The world consumption of energy in million tonnes of oil equivalent. Red slice indicates non-hydro renewables, most of which is wind.  (Courtesy of British Petroleum).|
Residential Solar power in the United States makes up a small percentage of energy that people consume; compared to the U.S.'s electric consumption of 437.9 gigawatts in 2013, less than one percent came from solar.  Such low reliance on renewable sources for energy is amplified in worldwide consumption as well (see Fig. 1). Americans currently get their electricity that is generated from burning coal, which has the negative outcome of emitting carbon dioxide. In 2013 alone, U.S. energy-related emissions totaled 5,405 million metric tons.  Solar power technology has been around since 1839, but has not yet become an economically feasible option for Americans to receive their electricity and significantly shift away from polluting sources of energy. 
As the EIA notes in its Annual Energy Outlook, installed PV capacity will reach 9.6 gigawatts in 2035 as a reference case, but that projection can grow to 60.5 gigawatts if there are extended policies supporting that growth.  This solar capacity growth is important if the country wants to move away from emitting dangerous amounts of carbon dioxide while still powering our homes. There is still a lot that has to happen before it can constitute a larger percent of American power production and be an economically viable option. Some policies that would allow for such capacity growth are tax incentives, subsidies, and net metering that would offset the price.  Solar power technology for residential purposes requires the installation of the solar panels facing the sun as well as connection to the grid. Smart grids and net metering are important in making solar power desirable, because it allows the possibility of homeowners selling power back to the grid.
The cost of installing solar panels is currently too high compared to the metered cost of conventional energy for most Americans. Even if someone wants to make the shift to solar photovoltaics, they have to pay an upfront cost between $25,000 and $30,000 for the installation of a 5-killowatt system, although some utility companies can offer incentives.  Often this up-front cost is a significant barrier that keeps people from making the transition despite the fact that solar is a viable option in many parts of the country.
Before the U.S. becomes carbon-free, it is important to tackle the large installation cost that is barring many people from installing solar power for their homes. The technology is there, but there needs to be substantial political support to lower the out of pocket costs for residents in order to move the country in the right direction.
© Laura Padilla. The author grants permission to copy, distribute and display this work in unaltered form, with attribution to the author, for noncommercial purposes only. All other rights, including commercial rights, are reserved to the author.
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