Perovskite and Tandem Solar Panels: What They Mean for Commercial Buyers
Updated 23 October 2026 · SEO Dons Editorial
What are perovskite and tandem cells?
Perovskite is a manufactured light-absorbing material. A tandem cell has two absorbing layers stacked together. Oxford PV, the maker whose pages are used here, describes a perovskite tandem cell as made of two components, one of them perovskite and, in its case, the other silicon. Silicon absorbs at the red end of the spectrum and perovskite can be designed to absorb at the blue end, so the stack captures more of the sun's light from the same area. The perovskite-silicon tandem is the version behind the products and records below: the perovskite cell is coated directly onto a silicon cell.
How efficient are they, and what is research versus product?
Most headline numbers are research cells, not modules on sale. The table keeps them apart and dates each one.
| Item | Figure | Status | Source and date |
|---|---|---|---|
| Record lab cell, perovskite-silicon tandem | 35.2% | Research cell, at least 1 cm² | Fraunhofer ISE report, version of 14 July 2026, citing the May 2026 Solar Cell Efficiency Tables |
| Record lab cell, perovskite alone | 26.9% | Research cell | Same report |
| Tandem module, 60-cell residential size | 26.9% | Record module, certified by Fraunhofer CalLab | Oxford PV release, 19 June 2024 |
| First tandem panels on the market | 24.5% module efficiency | Product; first shipment, to a US customer for a utility-scale installation | Oxford PV release, 5 September 2024 |
| Tandem modules today | 25% module efficiency | Product, as the maker's page reads | Oxford PV, page read 22 October 2026 |
| Commercial silicon modules | Just under 25%, from about 17% ten years earlier | Product | Fraunhofer ISE, July 2026 |
| A silicon back-contact module | Up to 25.5% | Product; datasheet version 202608 | Aiko product page, read 22 October 2026 |
Two cautions. The 26.9% figures are different things, one a cell and one a module. And the silicon benchmark moves with the author: Oxford PV's June 2024 release calls the best silicon modules about 25%, its FAQ says conventional modules typically max out around 20 to 22%, and Fraunhofer ISE reports just under 25%. When a tandem advantage is quoted as a percentage, check which silicon it is measured against. The NLR (formerly NREL) chart page, updated 14 August 2026, is the research-cell reference.
What is commercially available in 2026?
Only what makers state on their own dated pages can be reported. Oxford PV says it started commercialisation with a first shipment of 72-cell panels to a US customer on 5 September 2024, and describes this as the first commercial deployment of a perovskite tandem panel worldwide. On the page read for this article it says its second-generation modules carry a 10-year product and performance warranty, and that it expects the first tandem modules to be manufactured at volume from 2027. Those are the maker's statements, not independent confirmation.
What are the open questions?
- Stability. The IEA's February 2025 report on new module technologies says limited temperature stability and high ion mobility lead to unsolved degradation paths under normal operating conditions such as shading and high system voltage, and that no comprehensive solution is yet in the literature. Its authors relied on published literature because reliability data from commercial products were not available to them.
- Certification. Oxford PV says its modules have passed the relevant IEC tests, that existing IEC standards apply to tandems in some cases with engineering modifications, and that it is working with the standards community on the gaps. The IEA adds that the reverse-voltage behaviour of tandem cells under shade cannot yet be reproduced by standard qualification tests, and IEC TS 62804-1:2025 is not intended for tandem devices. The certifications guide sets out what the standards cover.
- Warranty. A 10-year product and performance warranty compares with a 30-year performance warranty on the 2026 silicon page used above; the lifespan and degradation guide shows how those curves work.
- Bankability. A screen like BNEF's counts bank-financed projects in the past two years. A technology whose first reported commercial shipment was in September 2024 has had little time to build that record.
Should a business wait?
Usually not. The test is simple arithmetic, and it only matters at all if roof area, not demand, limits the system. If the system is sized from daytime demand, higher efficiency adds no kWp; the sizing guide explains the difference.
For a hypothetical roof that fits 100 kWp of 22%-efficient modules (the same-area capacity is the efficiency ratio):
| Module | kWp on the same area | Gain on 22% silicon |
|---|---|---|
| Silicon at 22% (hypothetical) | 100.0 | None |
| Tandem at 25% (maker's page today) | 113.6 | 13.6% |
| Best silicon sheet above, 25.5% | 115.9 | 15.9% |
| Tandem at 27% (maker's 2027 target, not a product) | 122.7 | 22.7% |
Oxford PV's page says its 25% modules are already more efficient than conventional panels, but on these two figures the tandem product on sale does not beat the best silicon sheet. Even the maker's 27% target for 2027 would add 5.9% over 25.5% silicon (27 divided by 25.5). Waiting a year gives up a year of the array's output, and recovering it from a 5.9% gain would take about 17 years, before price, degradation or financing enter. Silicon is also still improving: Fraunhofer ISE's ten-year figure works out at roughly 0.8 percentage points a year.
Signals that would change the answer: a datasheet with a power warranty in the silicon range, certificates by model and edition that cover tandem behaviour, an independent bank-financed record, and a roof so area-limited that every square metre counts. The efficiency guide covers how to compare watts per square metre today, and the TOPCon, HJT and PERC guide covers the silicon cell types on offer. The datasheet lines to compare are on the commercial PV panels page. A reader weighing a quote against waiting can send an enquiry through this site's form.
Sources
- Fraunhofer ISE, Photovoltaics Report page and report PDF, version dated 14 July 2026, checked 22 October 2026.
- National Laboratory of the Rockies (formerly NREL), Best Research-Cell Efficiency Chart, last updated 14 August 2026, and its laboratory history (rename of 1 December 2025), checked 22 October 2026.
- Oxford PV, for its own products only, checked 22 October 2026: Technology; Mainstream (undated page, read on the check date); press releases of 5 September 2024 and 19 June 2024.
- IEA PVPS Task 13, Degradation and Failure Modes in New Photovoltaic Cell and Module Technologies, February 2025: executive summary and full report, checked 22 October 2026.
- IEC Webstore, IEC TS 62804-1:2025; BloombergNEF, Tier 1 Solar Module Methodology, 4 September 2026; Aiko, Comet 3N72 product page (that product only), checked 22 October 2026.
Common questions
Are perovskite solar panels available to buy in the UK?
Oxford PV's own pages describe a first commercial shipment to a US customer on 5 September 2024 and expect volume manufacture from 2027. Ask any supplier for the datasheet, IEC certificates and warranty terms before treating a tandem module as available for a UK roof.
Do perovskite panels last as long as silicon?
That is not yet shown. The IEA says no comprehensive solution to the multiple reliability issues of perovskite cells is in the literature, and the one maker's page read quotes a 10-year product and performance warranty for its second-generation modules, against 30-year performance warranties on 2026 silicon sheets.
What is the difference between a perovskite cell and a tandem cell?
A perovskite cell uses perovskite alone as the light absorber. A tandem stacks two absorbers, here perovskite over silicon. Fraunhofer ISE lists separate research records: 26.9% for perovskite cells and 35.2% for perovskite-silicon tandem cells.
Would a tandem module fit existing mounting and inverters?
Oxford PV says its modules are designed to be compatible with existing installations and offers 60-cell and 72-cell sizes. Check the datasheet's dimensions, weight, clamp zones and electrical values against the design, as with any module change.