How Much Technological Progress is Needed to Make Solar Hydrogen Cost‐Competitive?

Abstract

Cost‐effective production of green hydrogen is a major challenge for global adoption of a hydrogen economy. Technologies such as photoelectrochemical (PEC) or photocatalytic (PC) water splitting and photovoltaic + electrolysis (PV+E) allow for sustainable hydrogen production from sunlight and water, but are not yet competitive with fossil fuel‐derived hydrogen. Herein, open‐source software for techno‐economic analysis (pyH2A) along with a Monte Carlo‐based methodology for modelling of technological progress are developed. Together, these tools allow for the study of required technological improvement to reach a competitive target cost. They are applied to PEC, PC, and PV+E to identify required progress for each and derive actionable research targets. For PEC, it is found that cell lifetime improvements (>2 years) and operation under high solar concentration (>50‐fold) are crucial, necessitating systems with high space‐time yields. In the case of PC, solar‐to‐hydrogen efficiency has to reach at least 6%, and lowering catalyst concentration (<0.2 g L−1) by improving absorption properties is identified as a promising path to low‐cost hydrogen. PV+E requires ≈two or threefold capital cost reductions for photovoltaic and electrolyzer components. It is hoped that these insights can inform materials research efforts to improve these technologies in the most impactful ways.

Polymer Photoelectrodes for Solar Fuel Production: Progress and Challenges

“…While the fabrication process cost was not detailed, the price of the c-Si light absorber was 31% (48 USD/m 2 ) of the module cost . Another techno-economic analysis based on inorganic PEC to produce H 2 determined that the PEC cell was ∼80% of the total project cost . The LCOH 2 was at best ∼2 USD/kg, but the minimum cost of the PEC cell was 700 USD/m 2 .…”

“…398 Another techno-economic analysis based on inorganic PEC to produce H 2 determined that the PEC cell was ∼80% of the total project cost. 399 The LCOH 2 was at best ∼2 USD/kg, but the minimum cost of the PEC cell was 700 USD/m 2 . We are not aware of published technoeconomic analyses of polymer-based PECs at this time but we can look at those of OPV to gain further insights.…”

Grüner Wasserstoff direkt aus Sonnenlicht

“…Obwohl bereits vor 50 Jahren gezeigt wurde, dass dieser Prozess mit künstlichen Komponenten prinzipiell möglich ist, 4) mangelt es noch immer an Photokatalysatoren, um Wasserstoff im industriellen Maßstab (>1 t•Tag -1 ) zu produzieren. Grund dafür sind insbesondere zwei Probleme: 7) Diese Arbeiten helfen hoffentlich dabei, die photokatalytische Wasserspaltung an den Punkt zu bringen, dass sie weltweit zur Produktion grünen Wasserstoffs beitragen kann.…”

Toward a Hydrogen Economy: Development of Heterogeneous Catalysts for Chemical Hydrogen Storage and Release Reactions

“…4−11 It is predicted that these technologies will be implemented on a large industrial scale in the coming decades. 12,13 On the other hand, one of the well-known fuel cell technologies, proton exchange membrane fuel cells (PEMFCs), was significantly improved, and some of them have been already adopted in fuel-cell-powered vehicles. 14,15 Apart from the direct usage of hydrogen, various approaches for hydrogen storage after its green production and subsequent delivery for energy conversion processes are currently being intensively studied due to the extremely low volumetric storage density of gaseous hydrogen (2.5 Wh L −1 ).…”

“…In contrast to the combustion of fossil fuels, only water is produced as a byproduct in such hydrogen-based energy conversion processes. − However, still today most of the hydrogen produced is based on natural gas, nowadays so-called “grey hydrogen”. In contrast, “green hydrogen” production is driven by sustainable energy, e.g., solar, wind, and waste stream sources. − It is predicted that these technologies will be implemented on a large industrial scale in the coming decades. , On the other hand, one of the well-known fuel cell technologies, proton exchange membrane fuel cells (PEMFCs), was significantly improved, and some of them have been already adopted in fuel-cell-powered vehicles. , Apart from the direct usage of hydrogen, various approaches for hydrogen storage after its green production and subsequent delivery for energy conversion processes are currently being intensively studied due to the extremely low volumetric storage density of gaseous hydrogen (2.5 Wh L –1 ) . In this respect, the development of chemical H 2 storage–release technologies, so-called “chemical hydrogen batteries”, will help to bridge green hydrogen production and its utilization in energy vectors.…”