N-Type vs P-Type Solar Cells: Degradation and Heat Loss

Which is better, n-type or p-type? For new projects n-type is the standard, but the real answer sits on the datasheets of the two panels you are quoted. This page explains the difference in plain words, then compares one n-type and one p-type datasheet so you can see what the numbers look like. It does not give a price gap, because no source it uses compares the two.

Last updated: November 2026.

What is the difference between n-type and p-type cells?

The difference is the atom added to the silicon. Adding atoms on purpose is called doping. PVEducation, a solar course by Christiana Honsberg and Stuart Bowden, explains it this way.

Silicon has 4 valence electrons. A valence electron is an electron an atom can share to bond with its neighbors. A group V atom brings one extra electron. A group III atom brings one fewer, which leaves a hole.

Gallium is also a group III element. A gallium-doped cell is therefore p-type too.

Why does the doping atom matter?

Boron can combine with oxygen in the silicon and hurt the cell. PVEducation says the quartz crucible used to grow silicon ingots puts oxygen into the ingot. The oxygen is mostly harmless alone, but it forms complexes with boron that lower the carrier lifetime. Carrier lifetime is how long a charge stays free to produce current. A shorter lifetime means less power.

The same page says that n-type ingots made with phosphorus have similar oxygen levels but do not show this effect. It also says gallium-doped wafers do not show it. Source: PVEducation, Czochralski silicon.

Some makers use gallium instead of boron in p-type panels. LONGi’s Hi-MO 5 page says its “gallium-doped technology overcomes LID degradation”. LID is light-induced degradation, a power loss that starts when a panel is in the light. That is LONGi’s own claim.

JinkoSolar says the same kind of thing for its n-type panel: n-type modules with TOPCon offer “lower LID/LeTID degradation and better low light performance”. LeTID is light and elevated temperature induced degradation. This is also the maker’s own claim.

How much of the market is n-type?

Most of it. The Fraunhofer Institute for Solar Energy Systems (Fraunhofer ISE) published its Photovoltaics Report on 14 July 2026. It says silicon wafer technology was about 98% of production in 2025. It also says 86% of the wafers were n-type, using data from ITRPV (a yearly industry roadmap from VDMA, the German engineering industry association).

Source: Fraunhofer ISE, Photovoltaics Report, 14 July 2026.

Fraunhofer ISE says n-type TOPCon has become the dominant technology, and that n-type TOPCon and heterojunction (HJT) are replacing p-type PERC. TOPCon means tunnel oxide passivated contact. PERC means passivated emitter and rear cell. PERC is a cell design that is usually built on p-type silicon, so people often say “n-type vs PERC” when they mean “n-type vs p-type”.

For more detail on each cell design, see PERC vs TOPCon vs HJT field performance and IBC solar cells explained.

What do two real datasheets show?

Here is one n-type panel and one gallium-doped p-type panel, taken from the makers’ own pages. They are two products, not the whole technology. Another pair of panels could give a different result.

Sources: JinkoSolar Tiger Neo datasheet JKM625-650N-78HL4-BDV-F9-EN and LONGi Hi-MO 5 product page, both read in October 2026. STC means standard test conditions: 1,000 W per square meter of sunlight and a 25 °C cell.

Check the full LONGi datasheet for the cells marked “Not on the product page”. The Jinko datasheet is for a 2,465 by 1,134 mm bifacial panel. The LONGi page is for a 550 W panel of another size.

What does the efficiency gap mean on a roof?

Rated power equals panel area times efficiency times 1,000 W per square meter. Take 30 square meters of panel area as an example.

• 23.25% efficiency: 30 x 0.2325 x 1,000 = 6,975 W, about 6.98 kW.
• 21.3% efficiency: 30 x 0.213 x 1,000 = 6,390 W, about 6.39 kW.
• Difference: 585 W, or 9.2% more rated power from the same area (23.25 / 21.3 = 1.092).

The area of 30 square meters is only an example. Real panels have different sizes, so check each datasheet. The gain matters most when roof space is the limit.

What does the temperature coefficient mean?

The temperature coefficient says how much power a panel loses for each degree its cells get hotter than 25 °C. Datasheets give it for Pmax, the panel’s maximum power. Say the cells reach 60 °C on a hot day. That is 35 °C above the test value.

• Jinko, -0.29 %/°C: 0.29 x 35 = 10.15% below rated power.
• LONGi, -0.340 %/°C: 0.34 x 35 = 11.9% below rated power.

The 60 °C is an example, not a measured value. A lower number is better. See temperature coefficient for more.

What does the degradation number mean?

Degradation is the slow loss of power over the years. Jinko’s datasheet shows 1% in the first year and 0.40% a year after that. Over 30 years that is 99% - (29 x 0.4%) = 87.4%, which is the 87.4% at year 30 on Jinko’s chart.

NREL (the US National Renewable Energy Laboratory) reviewed published degradation rates in 2012. The median was 0.5% a year, and the average was 0.8% a year, across many module types. The studies were published before 2012, so they cover older panels than today’s. Source: Jordan and Kurtz, NREL/JA-5200-51664. Treat the datasheet number as the maker’s warranty promise, not as measured field data. For field data on newer cells, see our field performance page.

When can p-type still make sense?

P-type panels are still on sale, as the LONGi page shows. Two cases come up often.

• Matching an old system. If you add panels to an old array, the new panels must fit the old strings’ electrical limits. Ask the maker or your designer before you mix types.
• A better quote. If a supplier quotes a p-type panel at a lower price per watt, compare the datasheets in the same table as above. Look at efficiency, temperature coefficient, degradation and warranty, not only price.

Which is “better” depends on the two panels in front of you. Compare them with a yield model for your site. See bifacial gain if your site has a bright ground surface.

How do you compare two panels?

1. Put both datasheets side by side.
2. Write down efficiency, Pmax temperature coefficient, first-year and yearly degradation, and warranty terms.
3. Check the type the maker states: n-type, or p-type (boron or gallium).
4. Ask for a price per watt for both.
5. Run both in a yield model for your roof and shade.

For a deeper look at other technology choices, see monofacial vs other solar technologies.

Ready to compare modules inside a real design? Book a SurgePV demo, or check how shading analysis changes the gap between two panels on your roof.

Frequently Asked Questions

What is the main difference between n-type and p-type solar cells?

P-type cells use silicon doped with a group III element such as boron or gallium. N-type cells use silicon doped with a group V element such as phosphorus. Group III atoms leave holes in the silicon. Group V atoms add free electrons.

Are n-type panels better than p-type?

For new projects, n-type is now the main choice: n-type wafers were 86% of production in 2025. N-type avoids the boron-oxygen defect found in boron-doped silicon. Still, judge each panel by its own datasheet: efficiency, temperature coefficient, degradation and warranty. The two datasheets on this page show an n-type TOPCon panel at 22.36% to 23.25% efficiency and -0.29 %/°C, and a gallium-doped p-type panel at 21.3% and -0.340 %/°C.

Are p-type panels still sold?

Yes. LONGi still lists the Hi-MO 5, a 550 W module with gallium-doped technology, on its modules page. Gallium is a group III element, so this is p-type silicon. The market is moving to n-type, but p-type modules have not disappeared.

What is TOPCon, and is it the same as n-type?

TOPCon (tunnel oxide passivated contact) is one n-type cell design, not a name for all n-type cells. Fraunhofer ISE says n-type TOPCon and heterojunction (HJT) are replacing p-type PERC, and that n-type TOPCon has become the dominant technology.

What is the price difference between n-type and p-type panels?

This page does not give a price gap, because it does not use a source that compares the two. Fraunhofer ISE reports a global average module selling price of about 0.10 US$/Wp in 2025, for all technologies together. Ask suppliers for a quote in $/W for both types.

Does n-type make a difference for homeowners?

It can, mostly through higher efficiency and lower heat loss, but the gain depends on the exact panels you compare. For the same panel area, 23.25% efficiency gives about 9% more rated power than 21.3%. Compare the real datasheets for the panels you are quoted.

Do n-type panels degrade slower than p-type?

The two datasheets on this page cannot settle it. JinkoSolar’s n-type TOPCon datasheet gives 1% first-year and 0.40% yearly degradation, and LONGi’s p-type product page does not publish a figure. JinkoSolar claims lower LID and LeTID for n-type TOPCon, which is the maker’s own claim.