Producing biofuels from a fast-growing grass delivers vast savings of carbon dioxide emissions compared with petrol, a large-scale study has suggested.
A team of US researchers also found that switchgrass-derived ethanol produced 540% more energy than was required to manufacture the fuel. They also calculated that the production and consumption of switchgrass-derived ethanol cut CO2 emissions by about 94% when compared with an equivalent volume of petrol.
One acre (0.4 hectares) of the grassland could, on average, deliver 320 gallons of bioethanol, they added. Their paper appears in the Proceedings of the National Academy of Sciences.
Co-author Ken Vogel of the US Department of Agriculture’s (USDA) Agriculture Research Service, based at the University of Nebraska, Lincoln, said: “We had on-farm trials, so we had all the data from the farmers on all the inputs needed to produce the crops. We were able to take this information and put it into this model and able to come up with a very real-world estimate.”