History of Solar Cells
The photovoltaic effect was first recognized in 1839, but the first solar cell was not created until 1883. It used selenium as a semiconductor and gold to form junctions and was about 1% efficient. The first modern solar cells were accidently discovered at Bell Laboratories in 1954 and were about 6% efficient. In their early history, they were used primarily in the space program, but have slowly made their way over the decades into commercial and residential markets.
PV Government Policy
- The Japanese government, through its Ministry of International Trade and Industry, ran a successful program of subsidies for solar energy from 1994 to 2003. By the end of 2004, Japan led the world in installed PV capacity with over 1.1 GW.
- In 2004, the German government introduced the first large-scale feed-in tariff system, under a law known as the 'EEG' (Erneuerbare Energien Gesetz) which resulted in explosive growth of PV installations in Germany. To begin, the FIT was over 3x the retail price or 8x the industrial price. The principle behind the German system is a 20 year flat rate contract. The value of new contracts is programmed to decrease each year, in order to encourage the industry to pass on lower costs to the end users. The program has been more successful than expected with over 1GW installed in 2006, and political pressure is mounting to decrease the tariff to lessen the future burden on consumers.
- After seeing the success Germany had, Spain, Italy, Greece and France introduced feed-in tariffs. None have replicated the programmed decrease of FIT in new contracts though, making the German incentive relatively less and less attractive compared to other countries. The French FIT offers a uniquely high premium (EUR 0.55/kWh) for building integrated systems. California, Greece, France and Italy have 30-50% more insolation than Germany making them financially more attractive.
- In 2006 California approved the 'California Solar Initiative', offering a choice of investment subsidies or FIT for small and medium systems and a FIT for large systems. The small-system FIT of $0.39 per kWh (far less than EU countries) expires in just 5 years, and the alternate \"EPBB\" residential investment incentive is modest, averaging perhaps 20% of cost. All California incentives are scheduled to decrease in the future depending as a function of the amount of PV capacity installed.
- At the end of 2006, the Ontario Power Authority (Canada) began its Standard Offer Program, the first in North America for small renewable projects (10MW or less). This guarantees a fixed price of $0.42 CDN per kWh over a period of twenty years. Unlike net metering, all the electricity produced is sold to the OPA at the SOP rate. The generator then purchases any needed electricity at the current prevailing rate (e.g., $0.055 per kWh). The difference should cover all the costs of installation and operation over the life of the contract.