Material Insights · Understanding the Material World

Solar photovoltaics: Resources and labour

Land, steel, glass, silver and a lot of Asian factories

What this tab covers The natural resources (land, water, materials, fuel or feedstock) and the labour needed to capture this energy, per unit, with the reason each is needed.

PV needs no fuel and almost no water; its demands are land, bulk materials for frames and glass, purified silicon and small amounts of silver or rarer metals. About 96% of modules and components come from Asia.

Natural resources

ResourceHow muchWhy it is needed
LandMedian about 2,000 hectares per TWh a year for ground-mounted PV (about 20 m2 per MWh, calculated); close to zero for rooftops6Sunlight delivers a fixed amount of energy per square metre, and rows must be spaced so as not to shade each other.
Steel, concrete and aluminiumSteel 56-68 t, concrete 47-61 t, aluminium 7.5-19 t per MW (two estimates)78Steel piles and racking resist wind and snow; aluminium frames stiffen modules; concrete anchors inverters and substations.
Glass46-70 t per MW78Toughened low-iron glass protects the cells for decades while letting light through; it is the heaviest part of a module.
SiliconAbout 2.0 g per watt in 2024 (2 t per MW, calculated), down from 16 g per watt in 2004; older estimates 4-7 t per MW178Silicon is the light absorber; it is refined to very high purity, an electricity-intensive step, because impurities trap freed electrons.
Copper, silver and thin-film metalsCopper 4.6-7 t per MW; silver about 20 kg per MW (2018); CIGS needs about 10-27 kg indium and 3-7 kg gallium per MW78Silver paste forms cell contacts; copper carries current; indium and gallium form the CIGS absorber and are by-products of other metals.
WaterMedian about 1 gallon (4 litres) per MWh, range 0-59Only for panel washing; PV has no steam cycle needing cooling.

Labour

PhaseHow muchSkillsWhy it is needed
Whole life of a 50 MW plant229,055 person-days, about 4,600 per MW (calculated); 7.2 million people worked in solar PV worldwide in 2024, 58% in China810Technicians, electricians, engineers, lawyers and financiersWith no fuel, the work is in equipment.
Manufacturing and procurement22% of the total (50,225 person-days for 50 MW)8Factory workers and technicians (64%), industrial engineers (10%)Making silicon, wafers, cells, modules and inverters.
Installation and grid connection17% (39,380 person-days for 50 MW)8About 90% construction workers and technical staffPiling, mounting, cabling and the substation.
Operation and maintenanceAbout 56% of lifetime labour (13,560 person-days a year for 50 MW)8Construction workers and technicians for cleaning and repairs, safety experts, engineers and operatorsCleaning, vegetation control, repairs and monitoring over about 25 years.
Decommissioning2% (5,150 person-days for 50 MW)8Technical and construction workers (73%), truck drivers and crane operatorsRemoving modules and frames for recycling.

Sources

  1. Photovoltaics Report (updated 14 July 2026) Fraunhofer Institute for Solar Energy Systems ISE, 2026
  2. What are the land-use intensities of different energy sources? (summary of Lovering et al., PLOS ONE 2022) The Breakthrough Institute, 2022
  3. Raw materials demand for wind and solar PV technologies in the transition towards a decarbonised energy system (Carrara et al., EUR 30095 EN), Table 4 European Commission Joint Research Centre, 2020
  4. Renewable Energy Benefits: Leveraging Local Capacity for Solar PV IRENA, 2017
  5. Operational water consumption and withdrawal factors for electricity generating technologies: a review of existing literature (Macknick et al., Environmental Research Letters 7, 045802), Table 1 IOP Publishing (copy hosted by OpenEI), 2012
  6. Renewable Energy and Jobs: Annual Review 2025 (p. 20) IRENA and ILO, 2026