Material Insights · Understanding the Material World

Solar photovoltaics: Efficiency

How close silicon is to its limit, and what comes next

What this tab covers How much of the energy available is actually captured or extracted, in per cent: theoretical limits, laboratory records, typical new equipment and in-service averages, each with exactly what is being measured.

The average new silicon module turns about 23% of the sunlight falling on it into electricity, against a theoretical ceiling of 33.7% for any single-junction cell. Laboratory tandem cells, which stack two absorbers, have passed 35%. A working system delivers roughly three quarters to four fifths of what its modules are rated for.

Chart: Efficiency ranges

Theoretical limit Commercial Record In service

Efficiency by measure

MeasureRangeTypeWhat is measured
Shockley-Queisser limit, single-junction cell33.7%14Theoretical limitOne absorber with the ideal band gap (about 1.34 eV) in standard sunlight
Practical limit for a crystalline silicon cell29.4%15Theoretical limitSilicon's band gap (1.12 eV) is not ideal and some freed electrons recombine inside the crystal
Commercial crystalline silicon modules18.9 to 24.8%1CommercialSunlight to DC electricity at standard test conditions, Q4 2024; weighted average 22.7%
Record laboratory single-junction cells by material21 to 28.3%11718RecordCdTe 21.0%, CIGS 23.4%, perovskite 26.9%, silicon 28.1% (efficiency tables v68); LONGi silicon cell 28.29% (September 2026); best silicon module 26.4%
Record perovskite-silicon tandem cell35.2 to 35.5%1619RecordTwo stacked absorbers, so the single-junction limit does not apply: 35.2% (NREL chart), 35.5% (LONGi, July 2026)
Record III-V multi-junction cells39.5 to 47.6%161RecordThree to six III-V layers: 39.5% in normal sunlight, 47.6% under 665-fold concentration
Performance ratio of an installed system73.6 to 80%1In serviceShare of rated output delivered: 80% new, 73.6% over the life
Capacity factor, new utility projects worldwide16%2In serviceAnnual output divided by full rated output all year, 2025 global average

Where the energy is lost

StepLoss
Light not converted in the module (weak photons, surplus photon energy lost as heat, reflection)about 77% of incident sunlight for an average 22.7% module (calculated)1
Heat, wiring, soiling, mismatch and inverter losses when newabout 20% of rated output (calculated from an initial performance ratio of 80%)1
Module ageing over the lifea further 6.4 percentage points of performance ratio on average (calculated: 80% minus 73.6%)1

Module efficiency (about 23%) is measured under standard test conditions. The performance ratio (about 80%) is how much of that rating survives hot cells, cables and inverters. The capacity factor (about 16%) reflects night, cloud and sun angle, not any defect. With silicon cells near their 29.4% practical limit, research has moved to tandems.

Sources

  1. Photovoltaics Report (updated 14 July 2026) Fraunhofer Institute for Solar Energy Systems ISE, 2026
  2. Renewable Power Generation Costs in 2025 (Executive summary, Figure S1) IRENA, 2026
  3. Tabulated values of the Shockley-Queisser limit for single junction solar cells (Ruhle, Solar Energy 130, 139-147) Elsevier, 2016
  4. Reassessment of the limiting efficiency for crystalline silicon solar cells (Richter, Hermle and Glunz, IEEE Journal of Photovoltaics 3(4), 1184-1191) IEEE, 2013
  5. Best Research-Cell Efficiency Chart (Rev. 17 July 2026) National Laboratory of the Rockies (formerly NREL), 2026
  6. 28.13%, 26.4%! LONGi Sets New World Records for Crystalline Silicon Solar Cell and Module Efficiency (press release; module certified by NREL) LONGi, 2026
  7. 28.29%! LONGi Sets a New World Record for Crystalline Silicon Cell Efficiency (press release; certified by ISFH) LONGi (via TaiyangNews press releases), 2026
  8. LONGi Breaks World Record to 35.5% for Crystalline Silicon-Perovskite Tandem Solar Cell Efficiency (press release; certified by ESTI) LONGi, 2026