We got to look inside this multi-million dollar electrolyzer designed to split water molecules and make the hydrogen inside them into a green energy alternative that can compete with fossil fuels. Hydrogen has many benefits. It can be used as an alternative fuel source that doesn't produce greenhouse gases, as a means of storing excess electricity produced by renewables, or it can be used to make ammonia for agricultural applications like fertilizer. It's the Swiss army knife of molecules, if you will, and it all starts with really good green energy. The production of green hydrogen requires electricity to split water molecules (H2O) into hydrogen and oxygen. So, you can think of hydrogen not so much as a source of renewable energy, but rather a way to store energy for later use, either in a pipeline or in a tank. Compress it, liquefy it, transport it. But all hydrogen isn't necessarily green. Today, a lot of industries use hydrogen produced with methane or natural gas, and what we're doing is decarbonizing the use of hydrogen. Two of the biggest

hurdles preventing green hydrogen from becoming more widespread are the cost of renewable energy needed to split the water molecules and the cost of the equipment to make it happen. With renewables like wind and solar having reportedly achieved competitive pricing with fossil fuels in some areas, a feat known in the industry as grid parity, Verigy put its focus on lowering the cost of the electrolysis equipment itself, both to purchase and to operate. Verigy develops equipment for a process called alkaline water electrolysis. So, we pump potassium hydroxide into both the anode half-cell and a cathode half-cell. Those half-cells are separated by a membrane. On the anode, we produce oxygen; on the cathode, we're producing the hydrogen. Each cell can be taken out and either swapped or serviced independently for the rest of the system, and more cells can be added to increase hydrogen output. So, we can track the performance of each cell through time and proactively ascertain when a cell might need servicing, when it would be

advantageous to exchange a membrane or electrode. Smart cells can also be adjusted depending on the conditions. For example, they can be turned down when the cost of energy is high and turned up when the cost of energy is low. That dynamic operation of turn up and turn down is highly valuable when you think about coupling with renewables. Now let's get into some numbers. It takes about 10 L of water to produce a kilogram of hydrogen. What we're producing is a 20 megawatt electrolyzer, which is capable of producing over 8,000 kg of hydrogen a day. Think of that as being like equivalent to 8,000 gallons of diesel per day per electrolyzer. And what we plan to do is do multiple, multiple electrolyzers in any large scale plant. Verigy tells us its electrolyzers are 77 to 95% efficient, depending on the current density of the electricity coming into the system. It's millions of dollars for an electrolyzer, but you think about it in terms of cost per kilowatt. So we're

as competitive as anybody on the planet, to include our friends in low-cost regions of the world. That's what is really exciting because it means we've got the chance to build electrolyzers right here in the US and do so very, very inexpensively, at very large scale. Hydrogen is still emerging as an alternative to fossil fuels and battery technologies, and time will tell if Vert's plans, predictions, and innovations pay off. We think we're going to be at fossil parity before 2030, which means green hydrogen can be cheaper than its fossil fuel equivalent at very large scale globally. What role do you see hydrogen playing in a green energy future? Let us know down in the comments, and for more sustainable tech news, check out these videos right here. As always, thanks so much for watching. I'm your host, Jesse Oral. See you next time with the fam.

Making the Machines that Make Green Hydrogen

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