Charley, your inclusion of an article from Chemical Engineering - a respected, objective source, is appreciated. A lot of noise in hydrogen blogosphere, most of it from entities which stand to make a lot of money from selling hydrogen, with less regard for whether it is truly "green" throughout the supply / manufacturing / distribution chain.

From the article:

"During two demonstration campaigns, the facility will be powered by a mix of natural gas and hydrogen, ultimately aiming for up to 100% hydrogen operation. In this regard, the overall goal of the HyflexPower project is to test an entirely green hydrogen-based power supply for a completely carbon-free energy mix. This would save up to 65,000 tons of CO2per year for a SGT-400 at baseload operation."

1) "Up to 100% hydrogen operation...ultimately aiming..." are problematic. Will anyone really know whether the mix is 1% or 100%, other than the people who are selling the hydrogen/methane mix? Will hundreds of $millions be spent by electricity customers on machinery that can only save 650 tons of CO2/yr?

2) Let's assume 100% green hydrogen as a fuel source is achievable - the best possible scenario - and the SGT-400 can save up to 65,000 tons of CO2.

65,000 tons is nothing. In a world emitting 37,000,000,000 metric tonsCO2e/yr, it would require 569,230 of these systems, working at 100% capacity factor, to end global fossil fuel consumption. It would require an investment of $5.7 trillion just for SGT-400s - not including wind turbines, maintenance, or transmission sufficient to guarantee grids relying on hydrogen as a source of power will *never* run out of hydrogen. So that hospitals, schools, government could continue to function.

Before a dime of taxpayer / ratepayer money is spent on green hydrogen, someone needs to do a thorough cost accounting of whether it could possibly pay off. And I don't mean for vendors of the equipment or the fuel - they'll make out like bandits, even if it falls flat on its face. I mean for the environment, because making more renewable-things-that-look-green-but aren't is no longer an option.

Why is no one doing that accounting...are they afraid of discovering it's a hopeless fantasy?