Solar energy, a form of renewable energy, contributes only .11% of total US energy as of 2012 according to era.gov. However, many believe that the recent advances in solar technology and the reduction in cost will see solar energy comprise 10% of total production by 2025.
Solar energy comprises photovoltaics (solar panels), solar collectors, and solar hot water heaters. There are many variations of these solar technologies dating back to the 1954, when the first solar panels were developed for NASA.
Solar panels, or photovoltaics, generally lose about 1% efficiency per year. Also, they usually come with a 30 year guarantee. Solar panels have been regarded as reliable insofar as their durability and ability to produceconsistent energy (so long as the sun shines). However, solar power comprises a very limited amount of the national production due to it's prohibitive costs with long pay back periods, as well as, similar transmission losses and inconsistent energy production (similar to wind power).
(CC Image (right) showing solar availability worldwide circa 2006 with black dots representing total land required for solar energy to produce world's energy needs by Apteva [CC-BY-SA-3.0 (http://creativecommons.org/licenses/by-sa/3.0) or GFDL (http://www.gnu.org/copyleft/fdl.html)], via Wikimedia Commons)
Photovoltaics have and solar in general has been more widely used at a residential and commercial scale. Solar power has helped individuals, businesses, and local communities to become more resilient, self-sufficient, and more free from fossil fuels.
They still exists many problems with solar energy production on top of prohibitive costs. The perverse subsidies that contribute to a lack of funding, research, innovation, etc. into solar, neoliberal policies that prevent more sustainable technologies from making advancements, power storage issues, and technical issues that have stymied advancements in the field of solar power.
(CC Image courtesy of Michael Betke via Flickr)