The process accepts a wide variety of waste sources, including paper, old tires, textiles, and notably plastics, which it can handle very efficiently without toxic by-products. The bio-syngas exits the top of a plenum chamber, and is sent to a cooling chamber, followed by a pair of acid scrubbers to remove particulate matter.
A centrifugal compressor further cleans the gas stream, leaving a mixture of hydrogen, carbon monoxide and carbon dioxide. This is run through a water-gas shift reactor that adds water vapor and converts the carbon monoxide to carbon dioxide and more hydrogen gas. The two are separated, neatly capturing all the CO2 as hydrogen comes out the other end.
A Berkeley Lab lifecycle carbon analysis concluded, says SGH2, that each ton of hydrogen produced by this process reduces emissions by between 23 and 31 tons of CO2 equivalent – presumably counting emissions that would be created if the garbage was burned instead of converted into hydrogen. That would be between 13-19 tons more carbon dioxide avoided than any other green hydrogen production process.
What's more, while electrolysis requires some 62 kWh of energy to produce one kilogram of hydrogen, the Solena process is energy-positive, generating 1.8 kWh per kg of hydrogen, meaning the plant generates its own electricity and doesn't require external power input.
The 5-acre facility, in a heavy industrial zone of Lancaster, will employ 35 people full-time and create some 600 jobs in construction. SGH2 is hoping to break ground in Q1 2021 and achieve full operational status by 2023. The company is in negotiations with "California's largest owners and operators of hydrogen refueling stations" to buy the plant's entire output for a 10-year period.
SGH2 says it has demonstrated the technology at a full-size 7-year project in Pennsylvania, now dismantled, and a plasma torch testing facility in the Czech republic. The company says the technology "has been vetted and validated, technically and financially, by leading global institutions including the US Export-Import Bank, Barclays and Deutsche Bank, and Shell New Energies’ gasification experts." It has however, according to Power Magazine, not yet raised the US$55 million needed to build the plant.
Production and carbon emissions costs of different types of hydrogen production, as stated by SGH2
The numbers SGH2 presents are very attractive. We're not sure which methodology has been used to calculate the production costs, though, because they sure don't match up with the numbers in this 2019 Hydrogen Production Cost study, which shows several production methods coming in well under the US$2 per kg mark, and solar PV electrolysis costing as little as US$5.78 per kg. Perhaps the SGH2 table includes the capital costs of building each facility.
Either way, the pump price of hydrogen needs to get down around US$8 per kg before it roughly matches the per-mile cost of gasoline, assuming US$3.50/gallon (according to the California Fuel Cell Partnership). A production price around US$2 per kg should make that eminently possible.
We look forward to hearing more about this project; if hydrogen is going to happen as a substantial part of the new energy economy – and it certainly will, in Japan and Korea at the very least – then a cost-competitive and super-green way to produce it, while reducing landfill waste and disposing of difficult plastics, sounds like an excellent step in the right direction.
The company says it's in negotiations for similar projects in France, Saudi Arabia, Ukraine, Greece, Japan, South Korea, Poland, Turkey, Russia, China, Brazil and Australia.
Source: Newatlas