Green Tech

BP has proposed capturing carbon dioxide underground. A start-up in Texas called Skyonic says it can capture the gas and turn it into baking soda.

And now Carbon Sciences says it will turn carbon dioxide emissions from power plants and factories into calcium carbonate, otherwise known as limestone or chalk. The company combines the gas with fine calcium powders in a way that doesn't require a lot of heat and pressure, or that much calcium for that matter. For every ton of carbon dioxide, you only need three tons of raw materials, says CEO Derek McLeish.

The good news is that a lot of the raw materials exist as leftover tailings from mines, says McLeish. (Side note: McLeish also has set several land speed records at the Bonneville Salt Flats; it's a hobby.) So you are essentially taking environmental garbage, mixing it with pollution, and churning out a product that can then be sold to industrial manufacturers, who in turn won't have to ask miners to dig new holes in the ground to get calcium carbonate.

McLeish, in fact, showed us a prototype of how Carbon Sciences' system will work. It's in a van he drives around (See video). The chemical reaction that takes place in the van is powered by a solar panel on the roof.

Carbon sequestration will likely be inevitable--all three leading presidential candidates favor a cap-and-trade system, after all. The question now is how. Many believe that storing it underground will likely be the most practical way to do it, particularly when you think of the millions of tons of carbon dioxide that get produced. The gas will be liquefied before being inserted into the ground to increase storage. Some of the carbon dioxide can be pumped into oil fields to extract crude oil. However, a large percentage of the gas will just sit underground.

Converting carbon dioxide into solids does take raw materials and energy. McLeish (and Joe Jones of Skyonic), though, point out that the public isn't keen on storing a gas that can be hazardous to your health in large, underground caves. Still, carbon dioxide is a low-energy molecule. Converting it to other substances does require time, money, and energy. The efficiency of the processes will determine whether or not Skyonic or Carbon Sciences can become viable.

One sequestration technology you probably won't see, however, is using carbon dioxide to grow plankton in the ocean. , the people who had that idea, have run out of money.

There's no reason to think that technology will help reduce greenhouse gas emissions in the U.S. over the next 50 years, according to a new study from the Massachusetts Institute of Technology, but regulations and higher prices might.

The technology versus taxes--it's the primary green tech debate of the day. Nearly everyone would like to see inventions emerge that can curb emissions and reduce dependence on fossil fuels in an economical fashion. Many, however, say it's not feasible, particularly in the near term. Count this study in that latter camp.

Richard Eckaus, Ford International professor emeritus of economics, and Ian Sue Wing conducted a study on energy consumption and emissions in the U.S. from 1958 to 1996 and again from 1980 to 1996. The study also then projected forward and made predictions about what might happen from 2000 to 2050.

Their conclusion? Technology doesn't necessarily reduce energy consumption. As a result, the growth for energy use and emissions may accelerate by a half percent or more from the historical rates of 2.2 percent and 1.6 percent, respectively, over the next 50 years, even when some technological advances occur. (Note: This is total energy use, not energy use and emissions per GDP.)

One example of this phenomenon can be seen in steelmaking. Steelmakers switched from coal-burning plants to electrical plants in the past. However, since coal gets burned in power plants to generate electricity, the benefits from that switch were arguably negligible or negative. Emissions were cut, but that's because manufacturers began to use more scrap steel and cut down on iron ore.

"Technological change will not necessarily reduce dependence on fossil fuels. Energy taxes or a system of caps on energy use and trade in emissions permits are necessary," Eckaus said in a statement. "There is no a priori reason to think technology has the potential for reducing energy use while meeting the tests of economics. It's politically unappetizing in the U.S., but in Europe, gas costs $6 a gallon. Make energy more expensive: People will use less of it."

Novomer, a Cornell University spin-off, has devised a method for making biodegradable plastics from the common gases carbon dioxide and carbon monoxide.

The company on Wednesday announced that Physic Ventures and Flagship Ventures have invested $6.6 million, which Novomer will use to commercialize its technology.

The honey-colored goo that is the basis of different biodegradeable plastics.

(Credit: Novomer)

The plastics it intends to make could be used in a wide range of applications, including supermarket packaging, computer cases, plastic bottles, or foam to insulate buildings, said Novomer president Charles Hamilton. The company joins a growing number of green tech start-ups that are investing in bioplastics and other environmentally friendly materials.

"People have long dreamed about using carbon dioxide in this way but it's very hard to make it react chemically. That's why we put it in fire extinguishers," he said. "That's the breakthrough we have--to make it react without having to put a lot of energy into it."

Research behind the technology, patented by Cornell, was aimed at finding a catalyst that could combine carbon dioxide and carbon monoxide to make polymers.

The process, so far demonstrated on a small scale, calls for mixing a liquid metal with carbon dioxide or carbon monoxide in a reactor at low pressure. The end product contains about 50 percent of carbon dioxide by weight.

Depending on the feedstock and catalyst, Novomer can vary the output. For example, it may want to produce a more flexible plastic or one that doesn't decompose for a long time.

The company is still testing how biodegradable its plastics will be. It knows that the polymers made by other companies with carbon monoxide--called PHA (polyhydroxyalkanoates)--take about six months to decompose. Some of the plastics made with carbon dioxide have shown similar biodegradability, Hamilton said.

Initially, the company is pitching its plastics as a greener alternative to petroleum-based products. In the longer term, it expects to bring down the price so that the products are cheaper and better overall, Hamilton said.

Right now, Novomer is using gases that it purchases in tanks. But its plans call for constructing an eco-plastic facility at a spot that generates a lot of carbon dioxide or carbon monoxide, such as a cement plant, a facility that produces hydrogen, or a gasification facility.

"You can't have a cheaper feedstock than carbon dioxide. You actually get paid to use it," Hamilton said.