5 ways to turn CO2 into cash

These days, many experts are saying that we’re not going to be able to stop climate change just by decreasing emissions. To dig our way out of this hole, they say, we’re actually going to need to take carbon dioxide out of the air.

The first instinct has been to bury the CO2. Just pump it into the earth and try and forget how ashamed we are of these massive quantities of CO2. But a new breed of entrepreneur has sprung up, saying "If we have this CO2, why don't we do something useful with it?"

Obviously, we've got to get rid of all that carbon, but if folks can make some money and lower the cost of sequestration while they're doing it ... then that's just icing on the cake.

So here are five of the ways in which people are hoping to make bank with the millions of tons of CO₂ that are pumped out of coal plants and into the atmosphere every day.

Feed it to algae, and then turn the algae to fuel
You may know that biofuels can be made from algae. You may also know that algae thrives on carbon dioxide. A company called GreenFuel Technologies has put two and two together, and is using captured CO₂ to grow algae, which will then be made into biofuels.

But this isn't the only company working on it. There are dozens of start-ups working to create different techniques and algal strains that will allow them to maximize carbon capture and minimize costs.

Earth2Tech recently had a writeup on 15 of the top algae biofuel startups. Of all of the techniques listed there, algae farming with CO₂ is probably the most mature technology, and the first fuel-producing plants are already going online.

And, of course, we don't have to worry about ever running out of a market for biofuels. As long as we're creating CO₂ by burning fuels, there will be a place to burn biofuels.

Turn it into plastic
Recently the American Chemical Society saw a proposal to use captured CO₂ to produce polycarbonate plastics, like those used in CDs and DVDs. The idea is to take carbon dioxide emissions, and instead of sequestering them in the ground, trap them in resilient products.

This approach makes sense because it relies largely on sequestering carbon in disposable products, like plastic forks and water bottles. So, basically, we'd be sequestering carbon every time we threw away plastic.

Landfill sequestration seems like a pretty wasteful way to go to me, but it's certainly better than the alternative. But even with the amount of disposable plastic we consume in the world, we would have plenty of CO₂ left over if all of it was turned to plastic.

Make sodium bicarbonate (baking soda)
Joe David Jones, CEO of Skyonic, has created a process that captures CO₂ as it exits power plant smokestacks and mixes it with sodium hydroxide to form baking soda. This process, called SkyMine, also removes heavy metals and dangerous pollutants and coverts the CO₂ into sodium bicarbonate.

Baking soda has a variety of uses on the commercial market, and this process could help make carbon capture more economically viable. Even if the baking soda is not sold, because it is solid it is immensely easier to store it in old mines or landfills than it would be to sequester gaseous CO₂ beneath the ground.

The real question is whether the world can produce enough sodium hydroxide to keep the process going.

Calcium carbonate
A company called Carbon Sciences has a new process called GreenCarbon, which, at the base of things, turns carbon dioxide into useful stuff. The GreenCarbon process mixes the CO₂ with crushed calcium minerals, one of the most abundant elements in the earth's crust.

The end result is calcium carbonate, an industrial chemical that's used in thousands of applications, from PVC to paper to toothpaste and, in its pure form, as wall board and chalk. Because calcium carbonate is used in just about everything, there’s a huge market for it, and depending on the quality, it can sell for hundreds of dollars a ton.

The question remains, though ... is there enough of a market? The CEO of Carbon sciences says yes, but we're skeptical since a single coal plant could produce millions of tons of calcium carbonate per year.

Convert it directly into fuel
Sandia National Laboratories is working on creating fuel directly from CO₂ without any pesky biological intermediaries like algae. The carbon dioxide would be super-heated to around 1,200 C and mixed with water to create various hydrocarbons of the sort we're already burning in our cars. All of that heat, of course, is energetically expensive, but Sandia is hoping to use leftover heat from nuclear or utility-scale solar thermal power generating plants. The process basically reverses combustion, and is only economically viable if the energy can come from cheap, clean sources.

The good news is that it can be scaled up much more easily than algae production, which requires thousands of acres of space to soak up the CO₂ from one coal plant.

In conclusion
There's no one solution to this problem. We'll probably start out pumping most of it underground, while turning a good portion of it into fuel. But I expect that, in the next 20 years, when power producers start having to pay the true costs of releasing CO₂, techniques for creating useful products with that CO₂ will multiply.

Depending on where coal plants are and what resources they have around them, project planners will have to figure out what are the most economically viable things to do with the CO₂.

If there's a lot of calcium deposits around, they'll be creating calcium carbonate, but if there's a lot of sun and ample space, maybe algae farms will pop up around the power plant.

In any case, we'll see an entire economy spring up around actually using our societies primary waste product. And not only is that just good policy, it's a gigantic economic opportunity.