Turquoise hydrogen is produced by thermal decomposition of methane at high temperatures, from 600-1,200◦C.
The advantage of this process is that 3 kg of ‘carbon black’ are produced per kg of methane. This allows passable IRRs at lower costs than blue of green hydrogen.
The disadvantage is that methane decomposition is endothermic, thus an exterior energy source is required. If this energy source is natural gas, then around 2.6kg of CO2 will be produced by kg of hydrogen.
In turn, low-carbon turquoise hydrogen could be produced from low-carbon electricity (most likely a mixture of wind, solar, nuclear and hydro). Now the cost is more than blue hydrogen, but still very competitive versus green. This data-file quantifies the economics (above) and capex costs (below)
Remaining challenges are high capex costs at small scale, monetizing carbon black, the tendency of carbon ‘coking’ to clog up catalysts and reactors, the hunt for a reliable catalyst and ‘molten’ reactor design, and early technical readiness, as summarized in the final ‘notes’ tab of the model.