Prices and costs (1977–present) The average
price per watt dropped drastically for solar cells in the decades leading up to 2017. While in 1977 prices for
crystalline silicon cells were about $77 per watt, average spot prices in August 2018 were as low as $0.13 per watt or nearly 600 times less than forty years ago. Prices for
thin-film solar cells and for c-Si
solar panels were around $.60 per watt. Module and cell prices declined even further after 2014
(see price quotes in table). This price trend was seen as evidence supporting
Swanson's law (an observation similar to the famous
Moore's Law) that states that the per-watt cost of solar cells and panels fall by 20 percent for every doubling of cumulative photovoltaic production. A 2015 study showed price/kWh dropping by 10% per year since 1980, and predicted that solar could contribute 20% of total electricity consumption by 2030. The followed figures for select countries represent the cost per kilowatt of utility-scale solar generation, as well as price per kilowatt-hour in 2022 and a comparison with 2010. Dollars are in 2022
international dollars. Data are from IRENA.
Technologies (1980s–present) During the 1980s,
Professor Martin Green developed numerous technologies which made solar power generation more efficient. The sector faced price competition from Chinese crystalline silicon cell and module manufacturers, and some companies together with their patents were sold below cost. In 2013 thin-film technologies accounted for about 9 percent of worldwide deployment, while 91 percent was held by crystalline silicon (
mono-Si and
multi-Si). With 5 percent of the overall market, CdTe held more than half of the thin-film market, leaving 2 percent to each CIGS and amorphous silicon. The company profited from the booming Japanese market and attempted to expand its international business. However, several prominent manufacturers could not keep up with the advances in conventional crystalline silicon technology. The company
Solyndra ceased all business activity and filed for Chapter 11 bankruptcy in 2011, and
Nanosolar, also a CIGS manufacturer, closed its doors in 2013. Although both companies produced CIGS solar cells, it has been pointed out, that the failure was not due to the technology but rather because of the companies themselves, using a flawed architecture, such as, for example, Solyndra's cylindrical substrates. •
CdTe technology :The U.S.-company
First Solar, a leading manufacturer of CdTe, built several of the
world's largest solar power stations, such as the
Desert Sunlight Solar Farm and
Topaz Solar Farm, both in the Californian desert with 550 MW capacity each, as well as the 102 MW
AC Nyngan Solar Plant in
Australia (the largest PV power station in the Southern Hemisphere at the time) commissioned in mid-2015. The company was reported in 2013 to be successfully producing CdTe-panels with a steadily increasing efficiency and declining cost per watt. CdTe was the lowest
energy payback time of all mass-produced PV technologies, and could be as short as eight months in favorable locations. •
a-Si technology :In 2012,
ECD solar, once one of the world's leading manufacturer of amorphous silicon (a-Si) technology, filed for bankruptcy in Michigan, United States. Swiss
OC Oerlikon divested its
solar division that produced a-Si/μc-Si tandem cells to
Tokyo Electron Limited. Other companies that left the amorphous silicon thin-film market include
DuPont,
BP, Flexcell, Inventux, Pramac, Schuco, Sencera, EPV Solar, NovaSolar (formerly OptiSolar) and
Suntech Power that stopped manufacturing a-Si modules in 2010 to focus on
crystalline silicon solar panels. In 2013, Suntech filed for bankruptcy in China.
Silicon shortage (2005–2008) prices since 2004. As of July 2020, the
ASP for polysilicon stands at $6.956/kg Initially, the incumbent polysilicon producers were slow to respond to rising demand for solar applications, because of their painful experience with over-investment in the past. Silicon prices sharply rose to about $80 per kilogram, and reached as much as $400/kg for long-term contracts and spot prices. In 2007, the constraints on silicon became so severe that the solar industry was forced to idle about a quarter of its cell and module manufacturing capacity—an estimated 777 MW of the then available production capacity. The shortage also provided silicon specialists with both the cash and an incentive to develop new technologies and several new producers entered the market. Early responses from the solar industry focused on improvements in the recycling of silicon. When this potential was exhausted, companies have been taking a harder look at alternatives to the conventional
Siemens process. As it takes about three years to build a new polysilicon plant, the shortage continued until 2008. Prices for conventional solar cells remained constant or even rose slightly during the period of silicon shortage from 2005 to 2008. This is notably seen as a "shoulder" that sticks out in the
Swanson's PV-learning curve and it was feared that a prolonged shortage could delay solar power becoming competitive with conventional energy prices without subsidies. In the meantime the solar industry lowered the number of grams-per-watt by reducing wafer thickness and kerf loss, increasing yields in each manufacturing step, reducing module loss, and raising panel efficiency. Finally, the ramp up of polysilicon production alleviated worldwide markets from the scarcity of silicon in 2009 and subsequently lead to an overcapacity with sharply declining prices in the photovoltaic industry for the following years.
Solar overcapacity (2009–2013) As the
polysilicon industry had started to build additional large production capacities during the shortage period, prices dropped as low as $15 per kilogram forcing some producers to suspend production or exit the sector. Prices for silicon stabilized around $20 per kilogram and the booming solar PV market helped to reduce the enormous global overcapacity from 2009 onwards. However, overcapacity in the PV industry continued to persist. In 2013, global record deployment of 38 GW (updated EPIA figure IEA-PVPS published in 2014 historical data for the worldwide utilization of solar PV module production capacity that showed a slow return to normalization in manufacture in the years leading up to 2014. The utilization rate is the ratio of production capacities versus actual production output for a given year. A low of 49% was reached in 2007 and reflected the peak of the silicon shortage that idled a significant share of the module production capacity. As of 2013, the utilization rate had recovered somewhat and increased to 63%. the United States imposed tariffs of 31 percent to 250 percent on solar products imported from China in 2012. A year later, the EU also imposed definitive anti-dumping and anti-subsidy measures on imports of solar panels from China at an average of 47.7 percent for a two-year time span. Shortly thereafter, China, in turn, levied duties on U.S. polysilicon imports, the feedstock for the production of solar cells. In January 2014, the
Chinese Ministry of Commerce set its anti-dumping tariff on U.S. polysilicon producers, such as Hemlock Semiconductor Corporation to 57%, while other
major polysilicon producing companies, such as German Wacker Chemie and Korean OCI were much less affected. All this has caused much controversy between proponents and opponents and was subject of debate. == History of deployment ==