Wow.... I'm surprised. I thought Hydrogen (being such a small molecule) required very stringent pipeline requirements or else it could leak a lot. And, hydrogen leaks (correct me if I'm wrong) are much more likely to catch fire than others.
H2 problem is it takes more power to compress and vol/vol contains less energy than our typical fuel gasses. It has a low energy ignite, but the slightly good thing is that it's light, so it doesn't tend to collect in great volumes when there is a leak.
We have discussed some of the pros/cons of H2 pipelines here. At that time First Energy was considering a 30% mix of H2 in NatGas.
We're still a long way from producing enough clean hydrogen to exceed the capacity to mix into existing natural gas networks. IIRC oven burner elements designed for CH4 are good for up to 15% H2 content before needing modification.
Not sure about HDPE lines closer to the end users though. These already suffer from a small amount of through-wall CH4 leakage; leakage rate of the H2 fraction will be greater.
"Everyone is entitled to their own opinions, but they are not entitled to their own facts."
Interesting.... So, mixing H2 into natural gas would be a way to "boost" the energy output from natural gas turbines without increasing CO2 emissions?
Sounds like a modest step forward if it can be done cost efficiently. But, as I think ironi_metallurgist pointed out, the biggest hurdle is how scalable this is. If we can't do a lot of it, then it may not help much.
Hydrogen lacks the "punch" of Nat Gas ... you have to push 3 to 4 times the volume of hydrogen to match the BTU/scf of Nat Gas (methane)
The electrical energy output would not be "boosted" by use of hydrogen in a Combustion Turbine ... but the emissions would certainly improve and there would be less CO2 emitted.
Although SE, SIEMENS and others have evaluated CT performance with Methane/H2 fuels, I do not believe that there have been any studies on the effects on HRSG performance. If Combined Cycle HRSG performance is significantly degraded because of the water entrained in the exhaust, it will be a significant blow against the new Hydrogen economy.
These CC studies have not been done, and in my opinion are very important.
It's taking advantage of a fully developed distribution infrastructure, which was built over decades at massive total investment. That offers the potential for tremendous cost saving, even if there is a decrease in thermal delivery - how bad can it be at 10% H2 content?
"Everyone is entitled to their own opinions, but they are not entitled to their own facts."
I used to chat with a pipeline inspector for natural gas. He said some interesting things, primarily that the distributor expects to lose some 5-10 percent of the gas during transmission. Mostly residential stuff. He says they often transmit through holes in the ground where pipes used to be.
You can get lost reading the papers on pure hydrogen combustion and hydrogen with O2+CO2 combustion.
The CO2 comes from EGR.
Hydrogen leaks a bit worse than heavier gases, but nothing like He.
