Growth of photovoltaics

Source: Wikipedia, the free encyclopedia.

Benefitting from favorable policies and declining costs of modules, photovoltaic solar installation has grown consistently, with China expected to account for 50% of new global solar photovoltaic projects by 2024.[1][2]

Between 1992 and 2023, the worldwide usage of photovoltaics (PV) increased exponentially. During this period, it evolved from a niche market of small-scale applications to a mainstream electricity source.[3] From 2016-2022 it has seen an annual capacity and production growth rate of around 26%- doubling approximately every three years.

When

conventional energy sources. In the early 21st century a market for utility-scale plants emerged to complement rooftop and other distributed applications.[5] By 2015, some 30 countries had reached grid parity.[6]
: 9 

Since the 1950s, when the first solar cells were commercially manufactured, there has been a succession of countries leading the world as the largest producer of electricity from solar photovoltaics. First it was the United States, then Japan,[7] followed by Germany, and currently China.

By the end of 2022, the global cumulative installed PV capacity reached about 1,185 gigawatts (GW), supplying over 6% of global electricity demand,[8] up from about 3% in 2019.[9] In 2022, solar PV contributed over 10% of the annual domestic consumption of electricity in nine countries, with Spain, Greece and Chile over 17%.[8]

Official agencies publish predictions of solar growth, often underestimating it.

terawatts (4,674 GW) in its high-renewable scenario, of which more than half will be deployed in China and India, making solar power the world's largest source of electricity.[14][15]

Solar PV nameplate capacity

gigawatt (GW). Because power output for variable renewable sources is unpredictable, a source's average generation is generally significantly lower than the nameplate capacity. In order to have an estimate of the average power output, the capacity can be multiplied by a suitable capacity factor
, which takes into account varying conditions - weather, nighttime, latitude, maintenance. Worldwide, the average solar PV capacity factor is 11%.[16] In addition, depending on context, the stated peak power may be prior to a subsequent conversion to alternating current, e.g. for a single photovoltaic panel, or include this conversion and its loss for a grid connected photovoltaic power station.[17]: 15 [18]: 10 

Wind power has different characteristics, e.g. a higher capacity factor and about four times the 2015 electricity production of solar power. Compared with wind power, photovoltaic power production correlates well with power consumption for air-conditioning in warm countries. As of 2017, a handful of utilities have started combining PV installations with battery banks, thus obtaining several hours of dispatchable generation to help mitigate problems associated with the duck curve after sunset.[19][20]

Current status

Main article: Solar power by country
Solar generation by country, 2021[21]

In 2022, the total global photovoltaic capacity increased by 228 GW, with a 24% growth year-on-year of new installations. As a result, the total global capacity exceeded 1,185 GW by the end of the year.[8]

Asia was the biggest installer of solar in 2022, with 60% of new capacity and 60% of total capacity. China alone amounted to over 40% of new solar and almost 40% of total capacity, but only 30% of generation.[21]

North America produced 16% of the world total, led by the United States. North America had the highest capacity factor of all continents in 2022 at 20%, ahead of South America (16%) and the world at large (14%).[21]

Almost all of the solar in Oceania (39TWh) was generated in Australia in 2022, in either case amounting to 3% of the world total. However, Oceania had the highest proportion of electricity that was solar in 2022 at 12%, ahead of Europe (4.9%), Asia (4.9%) and the world overall (4.6%).[21]

History of leading countries

See also: Timeline of solar cells
The growth of solar PV on a semi-log scale since 1996

The

gigawatts. In 2015, China surpassed Germany to become the world's largest producer of photovoltaic power,[22]
and in 2017 became the first country to surpass 100 GW of installed capacity. Leading countries per capita in 2022 were Australia, Netherlands and Germany.

United States (1954–1996)

The

Vanguard I, the first solar powered satellite
launched into orbit in 1958.

In 1977 US-President

rooftop PV systems and power stations
. By 1996, solar PV capacity in the US amounted to 77 megawatts–more than any other country in the world at the time. Then, Japan moved ahead.

Japan (1997–2004)

electric grid paralyzed the entire infrastructure, including gas stations that depended on electricity to pump gasoline. Moreover, in December of that same year, an accident occurred at the multibillion-dollar experimental Monju Nuclear Power Plant. A sodium leak caused a major fire and forced a shutdown (classified as INES 1). There was massive public outrage when it was revealed that the semigovernmental agency in charge of Monju had tried to cover up the extent of the accident and resulting damage.[29][30]
Japan remained world leader in photovoltaics until 2004, when its capacity amounted to 1,132 megawatts. Then, focus on PV deployment shifted to Europe.

Germany (2005–2014)

In 2005,

feed-in tariffs
were adopted as a policy mechanism. This policy established that renewables have priority on the grid, and that a fixed price must be paid for the produced electricity over a 20-year period, providing a guaranteed return on investment irrespective of actual market prices. As a consequence, a high level of investment security lead to a soaring number of new photovoltaic installations that peaked in 2011, while investment costs in renewable technologies were brought down considerably. In 2016 Germany's installed PV capacity was over the 40 GW mark.

China (2015–present)

China surpassed Germany's capacity by the end of 2015, becoming the world's largest producer of photovoltaic power.[31] China's rapid PV growth continued in 2016 – with 34.2 GW of solar photovoltaics installed.[32] The quickly lowering feed in tariff rates[33] at the end of 2015 motivated many developers to secure tariff rates before mid-year 2016 – as they were anticipating further cuts (correctly so[34]). During the course of the year, China announced its goal of installing 100 GW during the next Chinese Five Year Economic Plan (2016–2020). China expected to spend ¥1 trillion ($145B) on solar construction[35] during that period. Much of China's PV capacity was built in the relatively less populated west of the country whereas the main centres of power consumption were in the east (such as Shanghai and Beijing).[36] Due to lack of adequate power transmission lines to carry the power from the solar power plants, China had to curtail its PV generated power.[36][37][38]

History of market development

Prices and costs (1977–present)

Swanson's law–stating that solar module prices have dropped about 20% for each doubling of installed capacity—defines the "learning curve" of solar photovoltaics.[39]
Price decline of c-Si solar cells
Type of cell or module Price per Watt
Multi-Si Cell (≥18.6%) $0.071
Mono-Si Cell (≥20.0%) $0.090
G1 Mono-Si Cell (>21.7%) $0.099
M6 Mono-Si Cell (>21.7%) $0.100
275W - 280W (60P)
Module
 $0.176
325W - 330W (72P) Module $0.188
305W - 310W Module $0.240
315W - 320W Module $0.190
>325W - >385W Module $0.200
Source: EnergyTrend, price quotes, average prices, 13 July 2020[40] 

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.[41]
Module and cell prices declined even further after 2014 (see price quotes in table).

This price trend was seen as evidence supporting

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.[42] 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.[43]

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.[44]

Country $ / kW
2022		 $ / kWh
2022		 $/kWh
2010		 %
down
Australia 923 0.041 0.453 -91%
China 715 0.037 0.331 -89%
France 1,157 0.062 0.423 -85%
Germany 996 0.080 0.401 -80%
India 640 0.037 0.376 -90%
South Korea 1,338 0.074 0.482 -85%
Spain 778 0.046 0.348 -87%
United States 1,119 0.058 0.235 -75%

Technologies (1990–present)

Global photovoltaics market share by technology 1980-2021. [45]: 24, 25 

There were significant advances in conventional

thin-film PV technologies, including amorphous thin-film silicon (a-Si), cadmium telluride (CdTe), and copper indium gallium diselenide (CIGS), led to the bankruptcy of several thin-film companies that had once been highly touted.[46] The sector faced price competition from Chinese crystalline silicon cell and module manufacturers, and some companies together with their patents were sold below cost.[47]

Global PV market by technology in 2021.[45]: 24, 25 

  CdTe (4.1%)
  a-Si (0.1%)
  CIGS (0.8%)
  mono-Si (82%)
  multi-Si (13%)

In 2013 thin-film technologies accounted for about 9 percent of worldwide deployment, while 91 percent was held by crystalline silicon (

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.[48]
: 24–25 

Copper indium gallium selenide (CIGS) is the name of the semiconductor material on which the technology is based. One of the largest
conversion efficiencies of over 15%.[49] 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.[50]
The U.S.-company
AC Nyngan Solar Plant in Australia (the largest PV power station in the Southern Hemisphere at the time) commissioned in mid-2015.[51] The company was reported in 2013 to be successfully producing CdTe-panels with a steadily increasing efficiency and declining cost per watt.[52]: 18–19  CdTe was the lowest energy payback time of all mass-produced PV technologies, and could be as short as eight months in favorable locations.[48]: 31  The company Abound Solar, also a manufacturer of cadmium telluride modules, went bankrupt in 2012.[53]
  • a-Si technology
In 2012,
Tokyo Electron Limited.[54][55] Other companies that left the amorphous silicon thin-film market include DuPont, BP, Flexcell, Inventux, Pramac, Schuco, Sencera, EPV Solar,[56] NovaSolar (formerly OptiSolar)[57] 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.[58][59]

Silicon shortage (2005–2008)

Polysilicon prices since 2004. As of July 2020, the ASP for polysilicon stands at $6.956/kg[40]

In the early 2000s, prices for

polysilicon
, the raw material for conventional solar cells, were as low as $30 per kilogram and silicon manufacturers had no incentive to expand production.

However, there was a severe silicon shortage in 2005, when governmental programmes caused a 75% increase in the deployment of solar PV in Europe. In addition, the demand for silicon from semiconductor manufacturers was growing. Since the amount of silicon needed for semiconductors makes up a much smaller portion of production costs, semiconductor manufacturers were able to outbid solar companies for the available silicon in the market.[60]

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.[61]

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)

Solar module production
utilization of production capacity in %