In June 1979 President Jimmy Carter made a huge investment by installing 32 solar panels on the White House roof. At the time, the price of photovoltaic cells hovered close to $40/watt. Seven years later Regan took the panels off again, and when President Obama put the White House back on the solar track just a few months ago, the price of solar PV cells had dropped to $0.74/watt. The difference amounts to an overall trend that has not only brought solar to grid parity in some parts of the country, but slashed the price of solar PV cells by 99 percent since 1977.

Climate Progress shows this extraordinary graph from Bloomberg New Energy Finance that depicts the declining costs of solar PV over the years. The price drop is most notable in the first 12 years as the technology took off, but it then stagnated between 2005 and 2009 as global market supply struggled to keep up with demand, according to NREL (pdf).
Since 2009, however, solar PV prices have continued to drop steadily to such an extent that companies are able to make a strong case for the switch to photovoltaics on a purely economic basis. As Xcel Energy Inc., proposed the addition of 170 megawatts of utility-scale solar in Colorado this year, their CEO David Eves explained to the Denver Business Journal that “This is the first time that we’ve seen, purely on a price basis, that the solar projects made the cut — without considering carbon costs or the need to comply with a renewable energy standard.”
As solar becomes the more attractive option, we’re seeing a clear uptick in its adoption. For the first time ever new solar capacity will top new wind capacity in 2013. Furthermore, a report from Navigant Research predicts that the price will continue to decline, causing the global solar PV market to exceed $134 billion by 2020, up a phenomenal 50 percent from this year. This means a potential 438 gigawatts of solar capacity will be added in the next seven years. Keep in mind, this year we are expected to see a record-breaking 36.7 gigawatts of solar PV capacity added.
It’s not just advances in technology and the subsequent decline in the cost of cells that is making solar PV more attractive. Scaling Green notes that Bloomberg New Energy Finance reported “a changing electricity industry context with regard to energy security and climate change concerns, increasing costs for some generation alternatives and a growing appreciation of the appropriate comparative metrics, PV’s competitiveness is changing rapidly.” However, BNEF points out that not all industry analysts are on pace with solar’s move into parity; instead, many people, including “commentators, policy makers, energy users and even utilities” labor under the misconception “that PV is prohibitively expensive, and still has not reached ‘competitiveness’.”
The news is still good. Bloombergreports that “[b]y 2017, the year after some U.S. tax incentives are cut, solar power will achieve grid parity “in most major markets.” If you want to see which markets are predicted to reach parity first, check out this fantastic interactive map from the Institute for Self-Reliance.
Via Think Progress