Imagine bacteria eating sunlight, and using this "energy" to produce the natural plant gas ethylene, the most important ingredient of plastic and polyester. Researchers at the National Renewable Energy Laboratory (NREL) are succesfully growing these bacteria. It would be a great step forward for the environment if this natural way to produce ethylene could eventually replace the petrochemical ethylene, as a derivative of petroleum. Main researcher Jianping Yu of the NREL already envisions farms making petrochemical replacements like ethylene in about 10 years time.