There are three fundamental areas where green technology would have a dramatic effect on a clean energy future – industrial chemicals, transportation fuel and cement manufacturing.
The industrial chemicals aspect is on track with the Aztlán Project, and now green fuel may be as well. Achíni Scientific announced that they have developed a way to make fuel from air and water, which they call Green Crude – green because it doesn’t add to the atmospheric CO2 burden and it burns cleaner than petroleum-based fuels.
It’s not the first time that someone has done this. In fact, this comes up a lot especially with auto makers. But this time might be different. Achíni is not trying to bring the production cost down, they’re just trying to find takers because they’ve already beat the price-points.
The world is completely dependent on hydrocarbon fuels, and we invest over six trillion dollars annually. We aren’t going to abandon that investment anytime soon. Even in a world of plug-in electric vehicles, there are no charging stations at sea or in the clouds, and international shipping and flights alone account for 8% of the UK’s greenhouse gas emissions.
Transitioning these fleets away from hydrocarbons will take decades, not possible in time to significantly stem global warming. But if we make the hydrocarbons green by taking CO2 out of the air, we won’t need to any time soon. And the fuels are drop-in replacements.
The products of combustion – CO2 and water – can be recombined using clean non-fossil energy, like wind, to re-cycle CO2 and make the same chemical fuels, like kerosene, gasoline and natural gas. That’s a closed carbon cycle, because the waste of the burned fuel becomes a feedstock for the future fuels.
Synthetic fuels are not new technology. The ability to turn coal into a crude oil is old tech, and the technology to turn natural gas into crude oil is currently deployed all over the world. There are many ways to turn CO2 and water into crude – Fischer-Tropsch, Methanol to Gasoline, and Gas-to-Liquids among others.
Synthetic fuels from air and water suffer from two major flaws. The first one is the high energy cost of hydrogen, and the second one is where to get all the energy it takes to make any meaningful amount of fuel.
How our grid electricity is priced is a fatal flaw in grid-connected synthetic fuel concepts. It has to do with the marginal cost of energy. Baseload like nuclear can’t rapidly increase and decrease output enough to match changes in electricity needs, so nuclear doesn’t set the price of electricity. Instead, the grid demands a source that can immediately increase and decrease electricity supply to match the demand and that always means having spinning reserves.
Today that is natural gas generation.
The price of natural gas generation sets the price of electricity, because it’s the last unit to be bought and all the generators get treated the same up. No matter how cheap or expensive the electricity generation is, it either rises to the price of natural gas or shuts off.
If the price of energy is set by natural gas, and you use that energy to split water to get hydrogen and capture carbon dioxide and do other work, then you have less energy than you started with, and if you’re using that carbon dioxide and hydrogen to make natural gas or crude oil, then either you’ve got a perpetual motion machine or a bankrupt entrepreneur.
Normal water electrolyzers don’t turn up and down any better or worse than nuclear reactors (3-5%/minute), and although very expensive batteries can carry you through an hour or so, the wind might be gone for more than a week. Because we don’t have an energy storage solution, large plants like water electrolyzers have to be grid connected, so that they never have to shut off.
Achíni Scientific solved this problem by developing intermittency technology that lets their plant run idle. So when the wind goes away for a week, their electrolyzers take a break. The long-term wind predictions are very accurate, so they can predict their monthly production well, and they are not hurt by day-to-day changes. Batteries don’t add to the total amount of wind energy over time (neither does Achíni’s technology), so the only difference between Achíni’s approach and battery storage is the price of the solution.
The cheapest redox flow batteries claim as low as 54$/kWh of storage capacity is possible. A midsized local water splitting plant would need ~$1,000,000,000 of that battery to store just one week of wind doldrums.
Achíni solved the energy storage problem by making it not a problem, and that means they can take their project off-grid, and that means they can go wherever the wind is rich and other assets are inexpensive, like land, ports, shipping lanes, and water.
Even better is you don’t have to make hydrogen. Instead, make value added-products and co-produce the hydrogen alongside them. It turns out that electrochemical cells for things like water splitting, or magnesium and other electrolyses always produce at least one other product. In the case of magnesium, magnesium metal is produced at one electrode (cathode) while chlorine gas is produced at the other electrode (anode).
In the case of water splitting, hydrogen is produced at the cathode while oxygen is produced at the anode. The oxygen is a waste product and that’s a huge loss. Here’s the trick though: an array of products can partner up to make hydrogen, and companies like Achíni and Orbital Farm figured that out. That includes chlorine, fluorine, iodine, the conjugate acid and base of any aqueous salt, and so on. Those products (like magnesium, titanium, chlorine, bleach, sulfuric acid, etc) already have their own markets – and the hydrogen comes with the package.
So the hydrogen is paid for by the secondary products, and the secondary products are made cheaper than any existing technology can do. And they’re all zero-carbon. Achíni’s solution even allows them to generate cement (calcium lime) without the release of the 2 billion tons of CO2 every year produced from heating limestone, and that cement is then able to absorb up to 700 million tons of CO2 per year out of the atmosphere while it cures.
After wiping out the cost of the hydrogen, the intermittency technology slashes the cost of capturing carbon dioxide, which is mostly an energy cost.
Among the many products that are possible from the combination of carbon dioxide and hydrogen, Achíni’s Green Crude using the Fischer Tropsch process can provide heavy paraffins for waxes and lubricants, olefins for making plastics and textiles and all of the other synthetic materials we use, making them green as well and removing them from the carbon cycle, so also carbon-negative.
The ultimate strategy is to access the richest and cheapest wind generation in the world – which is on remote, cold islands in the middle of the ocean with stranded, on-shore resources. These are surprisingly common. It turns out the US alone owns thousands of them. They can pump sea water and separate it into electrolytes and fresh water by mechanical vapor recompression using the wind energy, then use the fresh water for steam generation.
They then ramp up and down with the wind to produce hydrogen, as well as whatever co-products they’ve chosen for that production line. Those co-products are where the finances shine, and the optionality available to Achíni’s technology makes them resilient to market forces.
NREL has conducted studies of sample sites to calculate the cost of hydrogen from wind. But they used grid electricity for when the wind factor is low in order to maintain the electrolyzers at steady state. That grid electricity is quite expensive and easy to beat with Achíni’s idling technology.
Achini Scientific has taken a different approach to synthetic fuel. They didn’t focus on inventing a new synthesis, they figured out how to ramp with an extremely rich renewable energy source and where to find it.
It’s an energy solution to the synthetic fuel problem.