Special Grass Blades Can Act as CCS Technologies

Researchers say that plants with potential applications in biofuel production, such as the grass Miscanthus, could also fulfill another function, and namely trap carbon dioxide underground.

In this respect, the plant would basically be acting like a carbon capture and storage (CCS) technology, whose job is to clean smokestack emissions of the dangerous greenhouse gas.

Scientists are hopeful that Miscanthus will become the first type of blade of grass to boost energy efficiency while at the same time helping get rid of the CO2 already emitted in the atmosphere.

But these capabilities also raise a series of questions, scientists say. For example, should geneticists start modifying bioenergy crop plants so that they can start cleaning the atmosphere?

And, if the technology does prove efficient, can this be achieved on a scale large enough to ensure that global warming can be fended off for many years?

A team of scientists from two US Department of Energy (DOE) labs sought out to investigate the answers to these questions in a new analysis on the issue.

Expert Christer Jansson, from the Lawrence Berkeley National Laboratory (Berkeley Lab) and colleagues from the Oak Ridge National Laboratory (ORNL) were the main authors of the research.

“We want to encourage discussion and research on this topic. We need to explore the extent to which plants, and specifically genetically engineered plants, can reduce levels of atmospheric carbon,” Jansson says.

The expert holds an appointment as a senior staff scientist at the Berkeley Lab Earth Sciences Division. He is also the lead author of the new analysis, which is detailed in the October issue of the esteemed journal Bioscience.

One of the main opportunities the new research associated with engineering biofuel plants is boosting the amount of carbon dioxide that plants as a whole take out of Earth´s atmosphere annually.

Human activities emit about 9 gigatons of CO2 annually, of which only 3 gigatons are being engulfed by plants, researchers say. This level of pollution needs to be curbed soon, scientists agree.

But the 3 gigatons that plants absorb through photosynthesis are insufficient to curb global warming, experts say. Through genetic engineering, “we could double that in the next several decades,” Jansson says.

“By 2050, we could get to five or six gigatons of carbon removed from the atmosphere by plants, and I think a major part of that could come from bioenergy crops like grasses and trees,” the expert adds.

“They could make a big contribution in sequestering carbon, but other strategies will have to be used,” he concludes.