INSTITUTION PROFILE / PEROVSKITE SOLAR CELLS
Helmholtz-Zentrum Berlin (HZB)
The Berlin research centre that has repeatedly set tandem world records
HZB is a public research centre in Berlin, Germany, built around two pillars: running the BESSY II synchrotron light source and researching energy materials such as solar cells. In perovskite solar cells it is known for setting world records several times with perovskite-silicon and perovskite-CIGS tandems. HZB does not, however, have any power to regulate or certify; like everyone else, it has its records certified by outside test labs. This profile looks at one question only: how much influence HZB actually has over perovskite solar cells.
What this article covers
- HZB in 30 seconds
- What kind of body it is: the four types of influence
- What it does for perovskite solar cells
- How far its influence reaches (powers and geography)
- The companies and organisations involved
- Outlook
- Glossary, references and claim-to-source audit
1. HZB in 30 seconds
FULL NAMEHelmholtz-Zentrum Berlin für Materialien und EnergieHelmholtz Centre Berlin for Materials and Energy
COUNTRYGermanyThree sites: Adlershof and Wannsee in Berlin, and Jena
TYPE OF BODYA research centre of the Helmholtz AssociationThe association is made up of 18 centres in Germany
ESTABLISHED1 January 2009Formed by merging the Hahn-Meitner Institute (1959) and BESSY (1979)
STAFFAbout 1,500Including about 600 researchers, from 67 countries
BUDGETAbout €220 million a yearIncluding third-party funding. All fields combined
ROLE IN PEROVSKITE SOLAR CELLSRecord tandem cells, research and technology transferNo powers of regulation, certification or standard-setting
REACHResearch results are global; joint development centres on Germany and EuropeAbout 2,700 guest researchers from 28 countries visit each year (all fields)
The one thing to grasp first
HZB's influence comes from building record cells and showing what is possible. For perovskite-silicon tandems it raised the record to 29.15% in 2020, 29.8% in 2021 and 32.5% in 2022, and the 32.5% result was certified by Italy's ESTI (European Solar Test Installation) and included in the NREL chart Sourced. For perovskite-CIGS tandems, HZB says its 2020 record led to a new branch for this combination on the NREL chart Sourced. The current perovskite-silicon record, however, has passed to a company (LONGi, 35.2%). Alongside setting records, HZB also handles technology transfer to companies through PVcomB.
2. What kind of body it is: the four types of influence
Unlike the companies in this series, none of the institutions that appear in perovskite solar cell coverage mass-produces solar cells. What separates them is the route by which they influence the industry, and that gives four types.
3. What it does for perovskite solar cells
A history of its tandem records
| When | Combination | Efficiency | Certification and listing |
|---|---|---|---|
| September 2019 | Perovskite/CIGS | 23.26% | A world record as a certified value on 1 cm². Presented at the EU PVSEC international conference in Marseille, France |
| January 2020 | Perovskite/silicon | 29.15% | The data table gives FhG-ISE as the measuring lab |
| April 2020 (announced) | Perovskite/CIGS | 24.16% | A new perovskite/CIGS branch was added to the NREL chart |
| November 2021 | Perovskite/silicon | 29.8% | Achieved with periodic nanotextures (per HZB's 2022 announcement). The data table gives FhG-ISE as the measuring lab |
| December 2022 | Perovskite/silicon | 32.5% | Certified by ESTI and included in the NREL chart |
| February 2025 (announced) | Perovskite/CIGS | 24.6% | Certified by Fraunhofer ISE |
| June 2026 (announced) | Perovskite/CIGS | 25.5% | 1.081 cm². Listed as a record in the "green tables" (the efficiency tables in Progress in Photovoltaics), which require an area above 1 cm² |
On the NLR (formerly NREL) chart revised on 17 July 2026, the top perovskite/silicon result is LONGi's 35.2% and the top perovskite/CIGS result is KIER's 26.7% Sourced. The data table gives the area of the KIER record as 0.16 cm², so the area conditions differ from HZB's 25.5%.
Where the research happens
| Site or department | What it does | Link to perovskites |
|---|---|---|
| Department Perovskite Tandem Solar Cells | Develops high-efficiency perovskite tandems and studies optical and electrical loss mechanisms | Developed hole-selective self-assembled monolayers (SAMs) with Kaunas University. Two patents were filed, according to a 2019 announcement |
| HySPRINT Photovoltaics Lab | A lab for new material combinations and processes combining silicon and perovskites | The 2019 and 2020 perovskite/CIGS record cells were made and coated mainly here. Works closely with PVcomB |
| PVcomB (Competence Centre Photovoltaics Berlin) | Bridges research and industry. Has industry-oriented deposition and process equipment, and transfers technology through joint projects with companies and training of specialists | The 32.5% record was a joint effort by the PVcomB and HySPRINT teams |
| Outdoor performance testing | Tests everything outdoors, from cells under 1 cm² to mini-modules and full-size industrial modules from companies | HZB says its perovskite outdoor measurement series, running since early 2021, are "among the longest in the world" |
| Building-integrated PV (BIPV) | Operates a 380 m² PV façade as a living lab. Also runs BAIP, a consultancy office for building-integrated PV | A testbed for building-integrated uses |
A materials engineer's view: interface materials have driven the records
In every one of its record announcements, HZB credits the materials between the layers (the interfaces). In the 2019 perovskite/CIGS cell, SAMs of carbazole-based molecules with phosphonic acid groups covered the rough CIGS surface; for the 32.5% cell in 2022, interface modification reduced charge-carrier recombination losses; and for the 25.5% cell in 2026, the team screened combinations of nickel oxide (NiOx) and SAMs and fine-tuned how C60 is evaporated onto an ultra-thin (1 nm) lithium fluoride layer Sourced. For a materials supplier, this shows that hole-transport, electron-transport and passivation layers are now where differentiation happens. See also our explainer on tandem cells.
4. How far its influence reaches (powers and geography)
| Aspect | What HZB has | What it does not have |
|---|---|---|
| Powers | Research results and patents. A channel for technology transfer through joint and contract research (PVcomB) | Power to set regulations, subsidies or standards. Power to certify efficiency (its records are certified externally, by ESTI, Fraunhofer ISE and others) |
| Geography | Its records and papers are a worldwide reference. Joint research centres on German universities and EU projects (such as SOLMATES) | Any direct authority over other countries' markets or policies |
| Role in records | Has repeatedly updated perovskite/silicon and perovskite/CIGS records. Holds the perovskite/CIGS record under the above-1 cm² condition (June 2026 announcement) | The current perovskite/silicon record (LONGi's 35.2%) |
| Scale | About 1,500 staff and about €220 million a year (all fields) | No breakdown of staff or budget for photovoltaics or perovskites has been published |
A note on reading record figures
In a 2026 announcement, HZB explained that the NLR chart lists the highest value for each technology even for a cell of 0.001 cm², while the green tables require an area above 1 cm² Sourced. So the "world record for perovskite/CIGS" is KIER's 26.7% (0.16 cm²) on the chart but HZB's 25.5% (1.081 cm²) in the green tables: the answer depends on which table and which conditions you mean.
5. The companies and organisations involved
Links to the company profiles in this series
| Company | Link to HZB (as stated in primary sources) | Link to this series |
|---|---|---|
| Oxford PV | In NLR's data table, the maker of the 25.2% perovskite/silicon result of April 2018 is given as "Oxford PV/Oxford/HZB" (measuring lab: FhG-ISE) | See our Oxford PV profile |
HZB's photovoltaics research page says it has worked with companies including equipment and materials makers, but does not list them by name.
6. Outlook
| What the evidence suggests | Primary information it rests on | Category |
|---|---|---|
| HZB's strength is shifting away from the race for peak perovskite/silicon efficiency towards thin-film tandems with CIGS and records on practical areas above 1 cm² | Its 2025 and 2026 record announcements were both for perovskite/CIGS. The 2026 announcement stressed the record in efficiency tables that require an area above 1 cm², and also reported about 19.7% on a 2.25 cm² mini-module | Inference |
| HZB will become a reference point for perovskite/CIGS research aimed at film-type and lightweight uses (including space) | The 2020 announcement explained that an all-thin-film tandem well under 5 µm thick would allow flexible modules, is resistant to radiation and could suit satellites | Inference |
| Its long-term outdoor data will carry more weight in assessing durability | HZB describes its perovskite outdoor measurements, running since early 2021, as "among the longest in the world", and it also tests full-size industrial modules from companies | Inference |
7. Glossary
- Helmholtz Association
- An association of German research centres, made up of 18 centres including HZB.
- CIGS
- A compound semiconductor of copper, indium, gallium and selenium. Used in thin-film solar cells, and can be deposited on flexible substrates.
- SAM (self-assembled monolayer)
- A film one molecule thick that forms as molecules line up of their own accord. Used as the layer that extracts holes at the interface with the perovskite.
- ESTI
- The European Solar Test Installation in Italy. The NLR chart lists it as "JRC-ESTI", one of the labs that certify efficiency.
- Green tables
- The informal name for the solar cell efficiency tables published regularly in the journal Progress in Photovoltaics. They set conditions such as an area above 1 cm².
8. References
- HZB Facts and Figures: three sites, 18 Helmholtz centres, about 1,500 staff including about 600 researchers, about €220 million a year, about 2,700 guest researchers from 28 countries, and staff from 67 countries. https://www.helmholtz-berlin.de/zentrum/wofuer-wir-stehen/fakten_en.html
- HZB History of the Helmholtz-Zentrum Berlin: the merger on 1 January 2009, and the founding years of HMI and BESSY. https://www.helmholtz-berlin.de/zentrum/historie-hzb/index_en.html
- HZB Photovoltaics: scope of research, outdoor performance testing, the 380 m² PV façade, BAIP, PVcomB and HySPRINT, and cooperation with companies. https://www.helmholtz-berlin.de/forschung/unsere-forschung/photovoltaik/index_en.html
- HZB Department Perovskite Tandem Solar Cells: the department's aims, SAMs developed with Kaunas University, and certified values of 29.15% and 24.16%. https://www.helmholtz-berlin.de/forschung/oe/se/perovskite-tandemsolarcells/index_en.html
- HZB HySPRINT Photovoltaics Lab: hybrid materials of silicon and perovskites, and cooperation with PVcomB. https://www.helmholtz-berlin.de/forschung/quellen/corelabs/hysprint_en.html
- HZB Corelab PVcomB: bridging research and industry, and technology transfer through joint projects and training. https://www.helmholtz-berlin.de/forschung/quellen/corelabs/pvcomb_en.html
- HZB News, "World record for tandem perovskite-CIGS solar cell" (9 September 2019): 23.26%, EU PVSEC, SAMs, two patents. https://www.helmholtz-berlin.de/pubbin/news_seite?nid=20769&sprache=en
- HZB News, "Tandem solar cell world record: New branch in the NREL chart" (14 April 2020): 24.16%, a new branch on the chart, under 5 µm thick, space applications. https://www.helmholtz-berlin.de/pubbin/news_seite?nid=21263&sprache=en
- HZB News, "World record back at HZB: Tandem solar cell achieves 32.5 percent efficiency" (19 December 2022): ESTI certification, the NREL chart, 29.8%, PVcomB and HySPRINT. https://www.helmholtz-berlin.de/pubbin/news_seite?nid=24348&sprache=en
- HZB News, "HZB Sets New World Record for CIGS Perovskite Tandem Solar Cells" (4 February 2025): 24.6%, certified by Fraunhofer ISE, Humboldt University and TU Berlin. https://www.helmholtz-berlin.de/pubbin/news_seite?nid=28846&sprache=en
- HZB News, "CIGS-perovskite tandem cell achieves record efficiency of 25.5 %" (30 June 2026): 1.081 cm², the green tables, SOLMATES, HTW Berlin, and a mini-module at about 19.7%. https://www.helmholtz-berlin.de/pubbin/news_seite?nid=34446&sprache=en
- NLR Research-cell efficiency data table: measuring labs and dates for HZB's records, the "Oxford PV/Oxford/HZB" entry, and the area of the KIER record. https://www.nlr.gov/docs/libraries/pv/cell-efficiency-data-table.xlsx
- NLR Best Research-Cell Efficiencies (chart PDF, revised 17 July 2026). https://www.nlr.gov/docs/libraries/pv/cell-pv-eff.pdf
9. Claim-to-source audit
| Claim in the article | Category | Source |
|---|---|---|
| Three sites, 18 Helmholtz centres, about 1,500 staff and about 600 researchers, about €220 million a year, about 2,700 guest researchers from 28 countries, staff from 67 countries | Sourced | Reference 1 https://www.helmholtz-berlin.de/zentrum/wofuer-wir-stehen/fakten_en.html |
| Merger on 1 January 2009, HMI (1959) and BESSY (1979) | Sourced | Reference 2 https://www.helmholtz-berlin.de/zentrum/historie-hzb/index_en.html |
| Outdoor performance testing (measurements since early 2021), the 380 m² PV façade, BAIP, cooperation with companies | Sourced | Reference 3 https://www.helmholtz-berlin.de/forschung/unsere-forschung/photovoltaik/index_en.html |
| The tandem department's aims, and SAMs developed with Kaunas University | Sourced | Reference 4 https://www.helmholtz-berlin.de/forschung/oe/se/perovskite-tandemsolarcells/index_en.html |
| HySPRINT's aims and its cooperation with PVcomB | Sourced | Reference 5 https://www.helmholtz-berlin.de/forschung/quellen/corelabs/hysprint_en.html |
| PVcomB's role in technology transfer | Sourced | Reference 6 https://www.helmholtz-berlin.de/forschung/quellen/corelabs/pvcomb_en.html |
| 23.26% in 2019, presentation at EU PVSEC, the SAM materials, two patents, HySPRINT as the main site of the work | Sourced | Reference 7 https://www.helmholtz-berlin.de/pubbin/news_seite?nid=20769&sprache=en |
| 24.16% in 2020, the new branch on the chart, deposition at HySPRINT, under 5 µm thick and space applications | Sourced | Reference 8 https://www.helmholtz-berlin.de/pubbin/news_seite?nid=21263&sprache=en |
| ESTI certification of 32.5% and listing on the NREL chart, 29.8% in 2021, joint work of PVcomB and HySPRINT, interface modification | Sourced | Reference 9 https://www.helmholtz-berlin.de/pubbin/news_seite?nid=24348&sprache=en |
| 24.6% in 2025, certification by Fraunhofer ISE, Humboldt University and TU Berlin | Sourced | Reference 10 https://www.helmholtz-berlin.de/pubbin/news_seite?nid=28846&sprache=en |
| 25.5% in 2026, 1.081 cm², the difference in conditions between the green tables and the chart, SOLMATES, HTW Berlin, a mini-module at about 19.7%, NiOx, SAMs, LiF and C60 | Sourced | Reference 11 https://www.helmholtz-berlin.de/pubbin/news_seite?nid=34446&sprache=en |
| FhG-ISE as measuring lab for 29.15% and 29.8%, the "Oxford PV/Oxford/HZB" entry for 25.2% in 2018, and the 0.16 cm² area of the KIER record | Sourced | Reference 12 https://www.nlr.gov/docs/libraries/pv/cell-efficiency-data-table.xlsx |
| Current top values on the chart (LONGi's 35.2%, KIER's 26.7%) | Sourced | Reference 13 https://www.nlr.gov/docs/libraries/pv/cell-pv-eff.pdf |
| The four types of institution and HZB's place among them, and the choice of research partners in Fig. 2 | Our calculation | Our own classification and selection |
| Breakdown of staff and budget for photovoltaics or perovskites | Not yet confirmed | Not stated in references 1 or 3; this article does not estimate it |
| The three points in the outlook (section 6) | Inference | This article's reading of references 3, 8, 10 and 11 |
Last updated 25 September 2026 / Troy Technical
All figures come from HZB's official website and news releases, and from NLR's efficiency chart and data table. Items marked "Inference" are this article's reading of the primary information, not statements by HZB.