Crystalline silicon (c-Si) PV modules are built from silicon wafer cells. The cells are connected together and sealed between a transparent front, usually glass, and a plastic or glass backing. The technology comes in two types, monocrystalline and multi-crystalline (polycrystalline). The difference is whether the cell material has grain boundaries, which depends on the raw material and how the cells are made. Monocrystalline wafers are cut from one large single-crystal ingot, which is costly. Multi-crystalline wafers are cheaper, for example sliced from cast poly-silicon, but they are usually less efficient. Typical module efficiency is around 12 to 18 percent in one source and 15 to 20 percent in another. Poly-crystalline modules reach up to 17 percent. Silicon modules have a long field record. They usually lose under 1 percent per year and carry power warranties of about 25 to 30 years. As of January 2010, about 78 percent of installed PV plant capacity used c-Si. The rest used thin-film modules. Mainly p-type c-Si modules can lose power to light induced degradation (LID) and LeTID. Crystalline silicon modules are also tested for potential induced degradation (PID). Crystalline silicon reference sensors have the same spectral response as c-Si plant modules, so they are used to estimate a plant's STC power. Over a year they record about 2 to 4 percent less irradiation than pyranometers.
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related_toc1 drafted · lead Thin-film PV
Wafer-based crystalline silicon is the other main PV technology class, alongside thin-film deposition technologies.
sec=2.3.2 h=153861606c8asec=2.3.1 h=f7fb67df3e72c2 drafted · lead Solar cell
Crystalline silicon modules are made of interconnected PV cells encapsulated between a front sheet and a backing.
sec=2.3.2 h=153861606c8ac3 drafted · lead Light Induced Degradation (LID)
LID and LeTID mainly affect p-type mono and multi crystalline silicon modules.
sec=h69 h=bdc3ce4bcd6cc4 drafted · lead Potential Induced Degradation (PID)
Testing for PID is described for crystalline silicon PV modules.
tbl=2.r29 h=46b5b160cf61LeTID was first seen when PERC modules came to market.
sec=h69 h=bdc3ce4bcd6cdegradation_ratec6 drafted · lead ≤ 1 PERCENT-PER-YR
Conditions: Long-term performance degradation of silicon modules from field exposure
sec=3.2.1.1 h=cddff06cd0e8review note: support check: partial - Source says degradation is under 1 percent per year, which is close to but not exactly 'up to 1'; the condition matches.
efficiencyc7 drafted · lead 12–18 PERCENT
Conditions: Typical overall module efficiency of silicon solar modules (NREL landfill guide)
sec=3.2.1.1 h=cddff06cd0e8c8 drafted · lead ≤ 20 PERCENT
Conditions: Overall efficiency demonstrated by some monocrystalline module manufacturers, described as nearing this value
sec=3.2.1.1 h=cddff06cd0e8c9 drafted · lead ≤ 17 PERCENT
Conditions: Poly-crystalline silicon modules
sec=5.4.2 h=b9e435502fd2c10 drafted · lead 15–20 PERCENT
Conditions: Typical efficiency of a standard module with monocrystalline or polycrystalline cells (SMA document)
sec=h7 h=033da7168dd7typical_power_lossc11 drafted · lead 1–3 PERCENT
Conditions: LID in c-Si modules, occurring within the first days of sun exposure
sec=h69 h=bdc3ce4bcd6cc12 verified · fact ≤ 10 PERCENT
Conditions: LeTID in c-Si modules at temperatures above 50 °C, adding to LID loss
sec=h69 h=bdc3ce4bcd6cverified by: review-workflowverified on: 2026-10-24
subclass_of c1subclass_of c1related_to c4subclass_of c1related_to c2related_to c5related_to c1subclass_of c1