Photovoltaics
Turning light into electricity, then injecting it into a grid not designed for it. The technical challenge of PV is not the cell — it is the whole chain: array design, power electronics, DC safety, performance measurement and gigawatt-scale operation.
The main families
Silicon PERC, TOPCon, HJT
The market is shifting from PERC to TOPCon and heterojunction (HJT): higher efficiency, low temperature coefficient. Bifacial modules capture ground albedo. Commercial efficiency now exceeds 22%.
String, central, micro inverters
The inverter does MPPT, grid synchronization and increasingly ancillary services. String for commercial, central for ground-mount farms, micro-inverters and optimizers for shaded residential. Grid-forming is emerging.
Rooftop, ground, trackers, floating
Rooftops and carports, ground-mount farms on single-axis trackers (+15-25% yield), agrivoltaics and floating solar. Site choice drives the DC/AC ratio and annual yield.
Key challenges
- Design & yield — string sizing, DC/AC ratio, shading and mismatch, orientation and tilt: this is where the Performance Ratio is won or lost.
- DC safety — a PV array produces high-voltage DC whenever it is daylight: arc-fault detection (AFCI), rapid shutdown, grounding and insulation are vital for firefighters and maintenance.
- Commissioning & measurement — I-V curve, insulation test, drone infrared thermography: proving at handover that the array reaches contractual power (IEC 62446).
- Large-scale O&M — soiling and cleaning, drone thermal inspection, Performance Ratio tracking, early detection of failing modules across millions of panels.
- Grid integration — grid codes, voltage ride-through, curtailment at over-production hours, hybridization with storage to flatten the duck curve.
See also
Photovoltaics-specific standards
- IEC 61215 / 61730 — Module design qualification and safety (climatic, electrical and mechanical safety tests).
- IEC 62446 — Commissioning, documentation, inspection and testing (I-V curve, insulation, thermography) of grid-connected systems.
- IEC 61724 — Performance monitoring: Performance Ratio, availability, measurement accuracy classes.
- IEC 62548 / 60364-7-712 — DC array design and electrical installation rules on the DC side.
- IEC 62109 / IEC 62116 — Inverter safety and anti-islanding tests (disconnection on grid loss).
Related standard pages on IndustryHub
Major players
Modules
LONGi, JinkoSolar, Trina Solar, JA Solar, Canadian Solar, First Solar (CdTe).
Inverters
SMA, Sungrow, Huawei, Fronius, SolarEdge, Power Electronics.
Trackers & structures
Nextracker, Array Technologies, Soltec, STI Norland.
Developers & EPC
Iberdrola, EDF Renouvelables, Engie, Enel Green Power, NextEra.
Landmark facts
| Fact | Year | Source | Lesson |
|---|---|---|---|
| "The cheapest electricity in history" | 2020 | IEA report | The International Energy Agency calls well-sited utility PV the cheapest generation option ever seen, after module costs fell about 90% in a decade. |
| Potential-induced degradation (PID) | 2010 | Research | Discovery of power loss from array-to-ground voltages forced grounding, anti-PID cells and degradation tracking — a defect invisible without regular I-V testing. |
| Rooftop fires & rapid shutdown | 2014 | NEC 690.12 (USA) | Firefighter risk from live DC on rooftops mandated module-level rapid shutdown, then arc-fault detection (AFCI). |