Hydrogen Has Ten Production Routes. Only Some Will Survive Contact With the Grid
Everyone in energy has an opinion on hydrogen right now. Fewer people can actually name more than two or three of the ways it's produced — and fewer still can say, with any confidence, which of those routes will still make economic sense in a decade.
That gap is exactly what Hydrogen Production from Renewable Resources and Wastes (CRC Press, part of the multivolume Handbook of Hydrogen Production and Applications) is built to close. Edited by Mohammad Reza Rahimpour, Mohammad Amin Makarem and Parvin Kiani — a Shiraz University team with a research track record in catalytic fuel conversion and green hydrogen technologies — the book doesn't argue for or against hydrogen. It does something more useful: it lays out, process by process, exactly how hydrogen gets made from renewable and waste sources, and what each pathway actually costs in complexity, feedstock, and energy input.
Fourteen chapters, four families of technology
The structure alone tells you something about how fragmented this field still is. The book organizes fourteen chapters into four sections:
- Water splitting — electrolysis and thermochemical splitting, the two routes most people mean when they say "green hydrogen"
- Biomass and waste thermochemical conversion — pyrolysis and gasification of lignin, sewage sludge, and municipal biomass waste, plus liquefaction of algal material
- Biochemical conversion — biophotolysis, biological water-gas shift reactions, and fermentation, the least industrially mature but potentially lowest-energy-input pathways
- Other renewable resources — solar-, hydropower-, and geothermal-driven hydrogen production, including tidal, wave, and water-flow applications
That last section is worth pausing on. Most hydrogen coverage collapses into "electrolysis powered by renewables" and stops there. This handbook treats geothermal- and hydropower-driven hydrogen as legitimate, distinct production pathways with their own engineering literature — which matters if you're advising on, or researching, hydrogen strategy in a region where solar and wind aren't the dominant renewable resource.
Why this matters right now
We posted earlier this week about Clean Hydrogen for Decarbonisation, where two Oxford Institute for Energy Studies researchers made the case that hydrogen will win in specific hard-to-abate sectors — steel, cement, heavy transport — but won't replace oil economy-wide. That book answers the where question: which sectors justify the cost.
This handbook answers the how question underneath it. Because the honest answer to "should we invest in hydrogen" isn't the same for every production route. Electrolysis powered by curtailed renewable capacity is a very different cost and emissions story than gasification of municipal waste, which is a very different story again from geothermal-driven thermochemical splitting. Policymakers, engineers, and institutional researchers who only engage with the sector-level economics — without understanding what's actually happening inside the reactor — end up making the same mistake as people who evaluate "renewable energy" as a single technology instead of a dozen unrelated ones with wildly different maturity curves.
For academic and research libraries building out a hydrogen economy shelf, that's precisely the gap this handbook fills: a single structured reference standing between the high-level policy literature and the deep technical papers scattered across chemical engineering journals. Explore the full Energy collection for related titles.
Who actually needs this on the shelf
This isn't a book for someone looking for a hydrogen primer. It's written for people who already need the technical detail: chemical, environmental, and energy engineering researchers, hydrogen technology developers, and the academic libraries supporting them. If your institution has researchers working on catalyst design, gas separation, or renewable process engineering — or if hydrogen policy work is starting to run up against "which production pathway are we actually talking about" — this is the reference that resolves the ambiguity.
The bigger pattern
What strikes us most, reviewing hydrogen literature across both the policy and technical sides this month, is how often the two conversations happen in isolation. Policy researchers debate hydrogen's role using aggregate cost curves. Engineers debate individual reactor and process designs using metrics that never make it into the policy literature. Very few resources sit at the intersection and force the two conversations to meet.
That's the value of pairing a book like this with sector-level analysis like Clean Hydrogen for Decarbonisation: one tells you where hydrogen is worth pursuing, the other tells you which technical pathway gets you there most efficiently for a given feedstock and region.
Q&A
Q: What are the main methods used to produce hydrogen from renewable resources?
A: The main pathways are electrolysis and thermochemical water splitting, pyrolysis and gasification of biomass and waste, biochemical routes like biophotolysis and fermentation, and renewable-energy-driven production via solar, hydropower and geothermal sources.
Q: Is electrolysis the only way to produce green hydrogen?
A: No. While electrolysis is the most discussed route, biomass pyrolysis and gasification, biochemical fermentation, and geothermal- or hydropower-driven thermochemical splitting are all established alternative pathways, each with different cost and feedstock profiles.
Q: Can hydrogen be produced from waste materials?
A: Yes. The book dedicates multiple chapters to pyrolysis and gasification of sewage sludge and municipal biomass waste, as well as liquefaction of algal material, as viable waste-to-hydrogen pathways.
Q: How does this book relate to broader hydrogen economy debates?
A: It provides the technical production-side detail that underpins sector-level policy discussions — such as which industries hydrogen can realistically decarbonise — by explaining the cost and maturity of each production pathway individually.
Q: Who should read Hydrogen Production from Renewable Resources and Wastes?
A: Chemical, environmental and energy engineering researchers, hydrogen technology developers, and academic and institutional libraries building collections that support hydrogen economy research.