Strong oxide electrolyzers (SOECs) are rising to be a scorching matter on the earth of power. They use a strong ceramic materials to separate water into hydrogen and oxygen at extraordinarily excessive temperatures (600°C to 850°C). As a result of excessive working temperature, they’re additionally extremely environment friendly, hitting power effectivity ranges between 80-100%. These ranges are considerably greater than different dominant electrolyzers available in the market corresponding to Alkaline (AEL), Proton Trade Membrane (PEM), and Anion Trade Membrane (AEM), which often have effectivity ranges of 58-75%.
Nevertheless, while SOEC effectivity is unparalleled, the excessive prices and technical challenges related to SOECs make them appropriate just for particular, high-value use circumstances.
Notice: LHV 33.3 refers back to the decrease heating worth of hydrogen (33.3 kWh/kg), used to calculate SOEC effectivity by measuring the power content material of the hydrogen produced. It represents the usable power with out accounting for water vaporization.
The Promise of SOECs
SOECs are distinguished by their excessive effectivity, usually attaining Greater Warmth Worth (HHV) effectivity above 100%. Which means that the power output of the method can exceed the power enter, a uncommon and useful trait in power manufacturing applied sciences. This excessive effectivity ends in the manufacturing of high-purity hydrogen, which is essential for industries that require stringent high quality requirements, such because the artificial fuels sector.
Moreover, SOECs can use waste warmth and steam from industrial processes, making them much more environment friendly and cheaper to run. This can be a win for each value financial savings and sustainability in numerous industries.
The place SOECs Actually Shine
- Artificial Fuels: SOECs are notably appropriate for producing syngas (a mixture of hydrogen and carbon monoxide) for artificial fuels. The excessive purity of hydrogen means much less refining is required, making the entire course of cheaper and extra environment friendly. That is promising for the Sustainable Aviation Gasoline (SAF) business, which additionally has rising regulatory and manufacturing help. Offtake agreements corresponding to Norsk e-fuels with Sunfire, and Airbus with Genvia, are already in place.
- Steelmaking: The metal business can reduce CO2 emissions by 80-90% utilizing SOECs, as hydrogen can exchange carbon within the iron ore discount course of. The high-temperature atmosphere and the provision of waste warmth in metal vegetation align nicely with the operational wants of SOECs, additional growing effectivity. Initiatives like GrinHy with Sunfire and Salzgitter, and Ceres’ SteelCell improvement with Doosan, are key in demonstrating the viability of this use case.
- Nuclear Energy Crops: SOECs may be built-in into nuclear vegetation to provide hydrogen extra effectively utilizing the surplus warmth from the vegetation. This not solely boosts plant effectivity but additionally enhances security by lowering the necessity for exterior hydrogen provides. The mixing of hydrogen manufacturing inside nuclear vegetation also can assist in balancing the power grid, offering a versatile and dependable power supply. Corporations like FuelCell Power and Bloom Power are exploring this potential.
Company engagement by means of pilot demonstration vegetation and offtake agreements is essential for scaling up manufacturing from kilowatts (kW) to megawatts (MW). Such initiatives are already underway, indicating a rising curiosity and funding on this expertise.
The Roadblocks
Regardless of their advantages, the promise of SOECs comes at a excessive value—two to a few instances costlier than different electrolyzers. In addition they face technical challenges on account of their excessive working temperatures, which may result in sooner wear-and-tear and better upfront prices. Whereas excessive working temperatures may also help mitigate efficiency loss, in addition they induce thermal stress, growing the chance of stack failure by means of electrolyte cracking or seal breakage. SOECs can run at full load for about 2.5 years, whereas different electrolyzers can final 4-8 instances longer.
Moreover, SOEC expertise depends closely on electrical energy prices as a result of it wants loads of power to run the high-temperature electrolysis course of. It’s more cost effective in locations the place electrical energy is reasonable or there may be loads of reasonably priced renewable power. Then again, it struggles in areas with excessive electrical energy prices, unstable energy, or small-scale setups. SOECs want regular excessive temperatures and steady energy to work nicely, so areas with unreliable renewable power sources like photo voltaic or wind can have points until they use power storage options or sensible grid administration to easy out the ability provide.
Scaling manufacturing from kW to MW would drastically scale back manufacturing and materials prices and financial savings in complete stack value may be 67% to 77% when evaluating kW to MW scaled applied sciences. Nevertheless, only some innovators corresponding to Bloom Power and Topsoe have stacks at giant scales, that are important to exhibit technical maturity and long-term viability to buyers.
Innovating for the Future
Trying forward, the main target for SOEC expertise is on technical innovation and value discount. ‘Subsequent-generation’ SOEC expertise goals to handle the present limitations by bettering the sturdiness of supplies, optimizing design, and enhancing manufacturing processes. Some examples are:
Manufacturing Innovation:
- Mitsubishi Heavy Industries: Makes use of tubes as a substitute of sheets for stack manufacturing – simplifies fuel sealing and movement administration, resulting in improved efficiency reliability
- FuelCell Power: Makes use of disc-shaped stacks to chop prices by repurposing DVD manufacturing equipment; stacks are 95% recyclable
- Elcogen: Automating stack meeting to hurry up manufacturing and decrease prices
Materials and Design Innovation:
- Ceres: Makes use of a Gadolinium-doped ceria electrolyte, which permits for decrease temperature operation, and stack makes use of much less nickel – improves sturdiness and reduces prices
- Elcogen: Operates at a decrease temperature, permitting using cheaper parts corresponding to chrome steel as a substitute of specialised alloys
- Bloom Power: Reducing out deoxygenation models to simplify system design – reduces prices and upkeep wants
Integration Innovation:
- Topsoe: Integration of electrolyzer expertise with ammonia and methanol manufacturing, leveraging experience by means of their catalyst enterprise
- Sunfire: Crops working on a mixture of alkaline and SOEC electrolyzers, offering a robust benefit for the power-to-liquid and e-fuels markets
These developments are paving the way in which for SOECs to scale up and turn into extra reasonably priced. Because the power panorama shifts, SOECs may play an important position in a sustainable and environment friendly hydrogen economic system. Nevertheless, realizing this potential will depend upon continued innovation and company partnerships.