#20 HYDROGEN — BLUE OR GREEN?
The dramatic advances in carbon free electrical generation — mostly wind and solar — has meant that much of the focus on reducing our carbon emissions has been on converting the things that run on fossil fuel to electricity. This approach works great for home heating and most land transportation. Still, for some applications, like air travel, shipping and steel making, it’s hard to see a way forward for an electric-only approach. The current thinking is that “clean hydrogen” offers the path.
With the dawning recognition of the true price of our dependence on hydrocarbon energy, there was lots of talk about how hydrogen fuel was the answer. There is lots of water on earth, and water is H2O (two hydrogen atoms combined with one oxygen). All we need to do is get that hydrogen out of water and our troubles will be over, right? Well, unfortunately, it’s not quite that simple.
A tiny bit of chemistry here :(— the hydrogen in water has already been burned, bringing it to a much lower (more stable) energy state. Much as you can’t get any heat by trying to burn ashes in your wood stove, you can’t get any real energy from water. In order to bring that hydrogen back to a higher energy state where it can be useful as fuel, it must have its oxygen atom removed. It takes a lot of energy to do that. The value of hydrogen as a renewable energy source depends entirely on where that energy comes from.
The bipartisan infrastructure bill passed in 2021 includes 8 billion dollars as seed money for the building of “hydrogen hubs” designed to bring together a network of hydrogen producers, consumers, and connective infrastructure. Unfortunately, most hydrogen being produced today uses natural gas, both as the feedstock and for the energy needed to pry away elemental hydrogen. This process is not “clean” at all:
Carbon is stripped off the methane feedstock and released into the atmosphere.
CO2 is released in burning natural gas for powering the process.
Methane, a very potent greenhouse gas, is leaked into the atmosphere throughout the natural gas production system.
In the end, this process can be dirtier than burning coal!
Blue Hydrogen
Of course, the petroleum industry is salivating at the prospect of being an integral part of this profitable new market. They are putting their bets on “blue hydrogen”, a clever marketing term for a product that may be anything but renewable. Blue hydrogen will soon be the subject of an intense debate, as a powerful industry used to calling the shots in Washington fights to preserve its dominance in energy production. Advocates for blue hydrogen tout it as a bridge fuel, useful for supplying our energy needs until truly renewable sources are able to take over. They say that their process will capture up to 80% of the carbon released, storing it underground. But it’s worth remembering that:
Methane is not a renewable energy source.
Subterranean carbon sequestration is an undeveloped technology.
The natural gas industry has resisted efforts to eliminate methane leakage from wells and infrastructure.
Until these issues are addressed, blue hydrogen will be of no help in addressing climate change.
Green Hydrogen
The key to making truly clean hydrogen fuel is to employ electrolysis using renewably generated electricity. This is a very simple process, the subject of many a high school chemistry lab — essentially you immerse two electrodes in water and run direct current electricity through them. Hydrogen comes off one electrode, oxygen comes off the other. The technologies involved (wind turbines, photovoltaic panels and electrolysers) are already developed and in production. Electrolyser units are subject to the same economies of scale that have so dramatically reduced the costs of wind and solar power. There are several other promising hydrogen production technologies in the research stage. These may come to the forefront someday, but the point is that we have the means to produce green hydrogen right now.
Read how a whiskey maker in Scotland will generate clean hydrogen for its distillery — Green Hydrogen Systems
Want to try electrolysis in you own kitchen? YouTube
For the more technologically inclined, here is a link to new developments in green hydrogen production — Future Bridge
You can help:
Get in touch with your representatives in Washington. Tell them to forget their campaign contributions from the petroleum industry and work towards a green hydrogen standard that is truly green.
Thanks for reading,
Doug Hylan, Brooklin, Maine
“The oil and coal companies know that what they are doing is incompatible with a stable, healthy environment. Yes, they are right that without them there would be no global economy today. But unless they use their immense engineering talents to become energy companies, not just fossil fuel companies, there will be no livable economy tomorrow.” Thomas Friedman