Next-Generation Solar & Renewables

The French physicist, still a teenager, observed that light striking an electrode in a chemical cell generated a small electric current, the first observation of the basic effect that all later solar cells would exploit.

The word 'photovoltaic' entered English usage a decade after Becquerel's observation. Its coinage marks the point at which the effect had become a named subject of scientific study rather than an isolated curiosity.

His theoretical account of how light striking a material could release electrons, later recognised with a Nobel Prize, supplied the physical understanding on which all later semiconductor photovoltaic devices would be built.

American researchers demonstrated a cell efficient enough for real power generation, converting around six per cent of sunlight into electricity, turning a scientific curiosity into a technology with genuine, if still costly, practical applications.

The tiny American satellite's solar-powered radio transmitter operated for years in orbit, proving the reliability of photovoltaic power in a demanding application and establishing space as the technology's first major commercial market.

Created amid the 1970s oil shocks, the federal laboratory became the country's principal centre for solar research, driving decades of efficiency gains and cost reductions in photovoltaic cell technology.

At this price photovoltaics were viable only in specialised applications such as spacecraft and remote installations. The figure serves as the baseline against which decades of subsequent cost decline are measured.

Organic PV cells appeared in the 1980s with power conversion efficiencies of around 3%, and subsequent development pushed them beyond 15%. They offer an alternative, thin and flexible route to photovoltaic conversion distinct from crystalline silicon.

The Fraunhofer Institute measured a learning rate of some 25 per cent over these three decades. The consistent relationship between cumulative output and falling prices explains why deployment subsidies translated into lasting cost reductions.

The programme, led by Walter Sandtner in Bonn, was the first state scheme anywhere to subsidise rooftop photovoltaic installations. It created the template of public financing that later drove residential PV deployment across many countries.

Until then PV had largely been confined to specialised stand-alone applications. Connecting arrays to the electricity grid turned photovoltaics from a niche off-grid power source into a contributor to public electricity supply.

Japan launched the first large residential subsidy programme for rooftop solar, following the German model of subsidising household photovoltaic installations and covering 539 residential systems in its initial phase. Government grants for household photovoltaic systems built one of the earliest mass consumer markets for solar power and helped Japanese manufacturers take an early lead in cell production before Chinese competitors later overtook them; it also marked the internationalisation of state support for residential PV, after which many countries adopted similar financing.

The Renewable Energy Sources Act guaranteed above-market payments for solar electricity fed into the grid, driving a domestic installation boom that, together with parallel Japanese and Spanish incentives, gave the nascent global solar manufacturing industry its first large customer base.

The scheme created demand large enough for manufacturers to move from batch to mass production of photovoltaic modules. It is the point at which PV manufacturing achieved industrial scale.

Sustained state investment from 2000 onwards built Chinese solar production capacity to a scale that delivered major economies of scale. This investment was a principal driver of the global collapse in photovoltaic module costs.

Panel prices dropped fourfold over these years as manufacturing scaled and efficiency improved. The decline began the transformation of PV from a subsidised technology into a competitive electricity source.

The winery mounted 994 solar panels on 130 pontoons floating on its irrigation pond. The installation demonstrated 'floatovoltaics' as a way of deploying PV without competing for land use.

Wholesale module prices had stayed near $3.50–4.00/W in the early 2000s on strong German and Spanish subsidised demand and a polysilicon shortage. The abrupt end of Spanish subsidies after the 2008 market crash caused a rapid price fall, showing how dependent the young industry was on policy.

Governments created the intergovernmental body to provide policy advice, data and technical cooperation on renewables, giving solar power and other clean technologies a dedicated institutional home in international diplomacy.

Sharp's proprietary triple-junction design set a record for non-concentrating cells, with Boeing Spectrolab also achieving 40.7% with a triple-layer design. Such multi-junction work pushed the upper bound of what photovoltaic conversion could achieve.

Module prices dropped roughly tenfold across the decade, driven by Chinese manufacturing scale and efficiency gains. Inverter costs fell far more slowly, rising from a quarter of system cost in the early 2000s to over 61% of cost per kWp by 2019.

The sudden drop in late 2011 surprised the industry and drove a wave of solar manufacturer bankruptcies worldwide. Retail cell prices tracked by Solarbuzz fell from $3.50 to $2.43 per watt over the same year.

Massive increases in Chinese panel production cut module prices by over 90 per cent from 2011 levels. China also held 1048 GW of installed capacity against about 339 GW in the European Union, confirming its dominance of the technology.

The law introduced resilience and origin-related criteria alongside price in public procurement and auctions for solar equipment, an attempt to support what remained of Europe's solar manufacturing base against much cheaper Chinese imports.

Net metering rules crediting households and businesses for surplus generation kept distributed solar installation among the fastest-growing anywhere, making Brazil consistently one of the largest markets in the world for new small-scale solar capacity each year.

Load shedding, a near-constant feature of the previous two years, largely stopped after a surge in private rooftop and commercial solar installations added substantial capacity outside the state utility, alongside improved availability at Eskom's own power stations.

Developers in China and Europe pushed verified tandem-cell efficiencies well above the ceiling of conventional silicon panels, and the first small-scale factories making tandem modules began shipping limited volumes, a step toward a technology expected to enter mainstream production gradually.

Incentives under the production-linked scheme and rules restricting subsidised projects to domestically approved manufacturers pushed capacity higher, moving India toward becoming one of the world's largest producers of solar modules outside China.

International lenders and equity partners continued to back new utility-scale solar projects across the kingdom as part of the drive toward a target of half of electricity from renewables by 2030, extending a run of some of the world's lowest recorded solar tariffs.

The Swiss-based manufacturer cited an inability to compete with low-cost Chinese imports flooding the European market, closing production in Freiberg, Germany, and redirecting investment toward manufacturing in the United States, where incentives were more favourable.

Cells and panels shipped from Cambodia, Vietnam, Thailand and Malaysia were found to rely heavily on Chinese components routed around existing tariffs, and the new duties, some exceeding 100%, aimed to close a loophole that had made those countries leading suppliers to the US market.

Businesses and households bought Chinese-made panels in bulk to escape expensive and unreliable grid electricity, installing rooftop and ground-mounted systems largely outside formal utility programmes, in one of the most striking examples of consumer-driven solar adoption anywhere.

Annual additions rose for a third consecutive year, extending a run of growth that left China accounting for the large majority of the world's new solar capacity and deepening the country's dominance of the manufacturing supply chain from polysilicon to finished modules.

The World Energy Outlook stated that for projects with low-cost financing and high-quality solar resources, PV was now cheaper than any electricity source ever. The same year a Qatari bid priced solar at 0.015 US$/kWh.

Global photovoltaic capacity reached 1 TW, covering nearly two per cent of world electricity demand and making PV the third-largest renewable source after hydro and wind. Annual output exceeded 500 TWh of electricity.

Perovskite cells reached efficiencies comparable with commercial silicon in laboratory conditions. The result made perovskites the leading candidate to succeed or supplement crystalline silicon.

The record was achieved using multi-junction concentrator solar cells developed at the Colorado laboratory. It represents the highest conversion efficiency demonstrated for a photovoltaic device.

Utility-scale solar contracts in the US routinely priced under five cents per kilowatt-hour, while the lowest Persian Gulf bids reached about three cents. These prices demonstrated PV's competitiveness against conventional generation at wholesale level.

Domestic deployment scaled alongside the country's already dominant manufacturing base, beginning a period in which China's annual additions would come to exceed those of the rest of the world combined.

By this year PV production costs matched or undercut retail electricity prices in nineteen separate markets. The spread beyond California showed cost competitiveness was becoming global rather than local.

Prices continued their steep descent after breaching the $1.00/W barrier. Sustained falls at this rate underpinned PV's transition to a mainstream generation technology.

Washington ruled that Chinese manufacturers were selling panels below cost with the benefit of state support, opening a cycle of trade disputes between the world's largest solar market and its dominant manufacturing base that has continued in various forms since.

A global bibliometric study found solar PV formed the largest research body among seven sustainable energy types. The expansion of scientific output paralleled the technology's rapid commercial growth.

PV production costs fell to or below retail electricity prices in the state, though often still above wholesale coal or gas generation costs. Grid parity marked the point at which PV could compete on price without subsidy in a major market.