Solar photovoltaics (PV) offer one of the clearest pictures of how technology innovation can drive costs lower and improve the performance of a technology. The impact of economies of scale, learning-by-doing and process improvements in manufacturing, as well as at the project-level, do, however, obscure the overall picture.
• Solar module prices fell by up to 93% between 2010 and 2020, as the cumulative installed capacity of solar PV grew from 40 gigawatts(GW) to 710 GW.
• The typical, commercially deployed cell technology in 2020 consisted of mono-PERC 166 millimeter (mm) half-cut ‘pseudosquare’ cells placed in 72 cell modules with power ratings of 400 watts to 550 W. This was up from 156 mm ‘full square’ multi-C-Si aluminium back surface field (Al-BSF) cells in 2010 in 72 cell modules, with module power ratings of 250 W to 300 W.
Solar PV module cost reduction potential
Solar PV module price trends (2009 to 2021)
The decline of solar PV module costs has been an important driver of the technology’s improved competitiveness. Between December 2009 and December 2020, crystalline silicon module spot prices declined between 89% and 95% for modules sold in Europe, depending on the type. Increased economies of scale in manufacturing, reduced labour costs, falling material prices and materials use efficiencies, as well as process optimisations, have unlocked module cost reductions. In addition to these manufacturing cost drivers, an important driver of lower module costs per Watt (and, indeed PV
projects), has been the continuous increase in module efficiencies as a result of a shift to more efficient cell architectures – such as passivated emitter and rear cell (PERC) architectures becoming the state-of-the-art technology in modules. In 2021, the global solar PV module market has experienced supply chain disruptions, just like other sectors, leading to higher material costs or lower availability, pushing up prices.
Utility scale solar PV
Utility -scale: Total installed costs (2010 to 2020)
Total installed costsfor utility -scale solar PV plants fell by 81 % between 2010 and 2020 , from USD
4 731/kW to USD 883/kW . The global weighted -average total installed cost trend has remained remarkably consistent since 2016 , too . Since then, the annual reduction in the global -weighted average total installed costs was between 13 % and 17 % depending on the year, with the smallestreduction in 2020 . Since 2015 , the variation in total installed costs across markets has narrowed . There has been
a convergence, albeit not complete, towards best practice cost levels taking into account structural cost differences (e.g. due to labour ormaterials costs). Module price declines have driven the reduction in global weighted average total installed costs . Technology improvements have reduced materials intensity, efficiency improvements have reduced the area required for a given wattage, manufacturing processes have become increasingly automated and refined to reduce costs and economies of scale – particularly upstream in the module value chain – have borne fruit . At the same time, balance of system
(BoS ) costs have fallen thanks to the simplicity and modularity of utility -scale solar PV – from a development and installation perspective – increased developer experience, more competitive supply chains, larger project sizes (in some markets), and competitive procurement.
Residential and commercial solar PV
Residential and commercial sector PV installed costs (2010 to 2020)
Total installed costs in the residential rooftop PV market are higher than in the utility-scale market. Depending on the market, between 2010 and 2020, these costs decreased by between 46% and 85% following a declining cost trend in installed costs visible in a wide range of countries. Depending on the market, too, the total installed system costs decreased from between USD 4 326/kW and USD 7 844/kW in 2010, to between USD 658/kW and USD 4 236/kW in 2020. Since 2013, data for more markets beyond the earlyadopter markets has also become available. Between 2010 and 2020, total installed system costs in the commercial rooftop markets where data is available decreased between 69% and
88%. This corresponds to a change in the total installed cost range from between USD 5 466/kW and USD 8 632/kW in 2010 to between USD 651/kW and USD 2 974/kW in 2020 Since 2017, more data has become available, as new markets have emerged.
Concentrating solar power
Concentrating solar power (CSP) made remarkable progress over the 2010 to 2020 period, given that deployment has been modest, historically, and cumulative installed capacity is less than one-tenth
ofsolar PV. • Average project sizes increased from 54 MW in 2010 to 75 MW in 2020, with the emergence of commercial-scale solar towers (ST) to complement commercially-proven parabolic trough collector (PTC) plants. • Total installed costs for CSP plants fell by 50% between 2010 and 2020, from USD 9 095/kW to USD 4 581/kW. Growing developer experience, more competitive supply chains, projects in markets with more competitive labour and civil engineering costs, larger project sizes, and competitive procurement of projects have all contributed to the reduction.
Market development At the end of 2020 , CSO’s global cumulative installed capacity of CSP was less than 7 GW, a five -fold increase, globally, between 2010 and 2020. The early years of last decade saw the re emergence of CSP as a commercial technology, as a generous feed -in -tariff (FiT ) in Spain kick started a period of rapid development. Investment in the United States, funded under the US response to the 2007 -2009 global financial crisis, sustained deployment until 2014 . After modest activity in the period 2015 to 2017 , which saw annual additions of between 100 MW and 200 MW per year – the
global market for CSP grew during 2018 and 2019 . In those years, an increasing number of projects came online in China, Morocco and South Africa . Some 150 MW was likely commissioned in 2020 , although official statistics only capture 100 MW . Generation grew faster than deployment, given the increasing capacity factors of new plants.
Growth drivers Significant potential for growth in behind-the-meter applications remains. Notably, this is in small-scale systems associated with PV, enabling an increase in self-consumption, or, potentially, in response to incentives from grid operators and/or distribution companies to manage grid feed-in. Currently, where the right regulatory structure is in place (e.g. Germany), or in areas with high electricity prices, excellent solar resources and relatively low grid feed-in remuneration (e.g. Australia), significant battery storage associated with new PV installations continuesto emerge. In Germany, recent years have seen as much as 40% of total annual small-scale solar PV installations undertaken together with battery storage. The share of new PV systems installed with storage rose to about 60% during 2019, with preliminary reports putting this figure closer to 70% during 2020 (Figgener et al., 2021; BVES, 2021). PV systems help insulate home owners from experiencing brown-outs and blackouts that occur on a regular basis, not to mention the smaller off-gridmarketforsolar home systems.
Key insights The global weighted-average total installed cost for onshore wind fell 32% between 2010 and 2020, from USD 1 971/kW to USD 1 349/kW. The 2020 cost was also down 10% on the 2019
value of USD 1 491/kW. The country/region weighted-average total installed cost for onshore wind in 2020 ranged from around USD 1 038/kW-USD 3 189/kW. China and India have weightedaverage total installed costs between 20% to 67% lowerthan other
• Most markets experienced a peak in wind turbine prices between 2007 and 2010, with these falling between 44% and 78% by the end of 2020. That year, prices were in the range USD 700/kW to
USD 910/kW in most major markets, excluding China, where prices were around USD 540/kW due to contracts there that typically exclude logistics and towers.
• Technology improvements in turbines and the drive for cost reductions saw the global average rotor diameter increase from 82 m in 2010 to 119.4 m in 2020, a 46% increase. At the same time, the global average hub-height increased 27%, from 81.3 m in 2010 to 103.2m in 2020.
Market development The onshore wind market has grown almost fourfold from a total installed capacity of 178 GW in 2010 to 698 GW in 2020. Total electricity generation from onshore wind grew
by 993 TWh between 2010 and 2019, and by 1 061 TWh over the 10 years from 2009 to 2019 As for other renewable technologies, China has played a large, sometimes dominant role in driving capacity additions. Of the 105 GW added in 2020, China accounted for 69 GW, with the next largest market – the
United States – adding 14 GW, or just one-fifth of China’s new additions.
Rotor Diameter With recent years seeing more projects in China, Germany and Belgium – countries where projects tend to use larger rotor diameters – the weighted-average rotor diameter increased
by 44% between 2010 and 2020. In 2020, Germany and Belgium had a weightedaverage rotor diameter of 166 m, while in China it was 162 m. The weighted-average rotor diameter for Europe was 112 m in 2010. This value reached 163 min 2020 (a 46% increase).
Overview and key insights As the cost of renewable electricity hasfallen, interest in renewable
hydrogen as an energy carrier and storage medium has grown. Renewable hydrogen could provide an important feedstock for a decarbonised chemicals sector, provide energy in critical industrial
processes such as steel making, and be used either directly or in a converted form (e.g. ammonia) in transportation, as well as providing seasonal storage to balance variable electricity generation fromsolar and wind power, overthe year.
• Renewable hydrogen can be produced from renewable electricity in electrolysers that process water into hydrogen. These electrochemical devices split water into its constituent components, yielding hydrogen and oxygen by the passage of an electrical current.
• Electrolysers have been commercially deployed since the beginning of last century and a number of different types exist. The main commercial technologies, however, are alkaline (AEL) and proton
exchange membrane (PEM) electrolysers. There is significant ongoing R&D activity in the sector, while a relatively small number of companies exist that manufacture, perform system integration, and provide turn-key solutionsfor customers.
Solar thermal district heating in Denmark Denmark is a world leader when it comes to solar thermal district heating, with more than 1 GW thermal (GWth) in operation at the end of 2020 . Around 120 villages, towns and cities use solar heat in their municipality-owned district heating networks. The total installed cost of district heating scale solar heat in Denmark fell from a weighted average of USD 573/kW in 2010 to USD 409/kW in 2019. This was quite a remarkable achievement, given the market for new capacity was shrinking over this period. These installed cost reductions have made solar
thermal heating systems a competitive source of heat for district heating, as the weighted -average levelised cost of heat (LCOHEAT) fell from USD 0 .066/kWh in 2010 to USD 0 .045/kWh in 2019 . With no fuel price volatility, this allowed solar thermal district heating to achieve competitive results for
Offshore Wind Technology Evolution The geographical distribution of offshore wind projects in the 2009 to 2020 period remained constant, with Europe (the United Kingdom, Denmark, and Germany) and Asia (China and Japan) the frontrunners. Offshore wind farms were built much closer to the shore and at shallow depths in the early 2010. To reach the strongest and most consistent wind, RD&D activities have since driven wind farms farther from shore and into deep waters. A technical potential of over 13 TW can be reached in waters beyond 50 m, with an economically attractive option being floating offshore platforms.This can unlock potential in countries with large seabed drops, allowing wind farms to be located at much greater distance from shore (e.g. in Japan, China,the United States and Europe).