Virent Energy Systems' biogasoline has passed a major road test. A trial conducted by Royal Dutch Shell, one of Virent's collaborators, tested five identical pairs of late-model European cars. Each car was driven more than 6,000 miles during 2010. One set ran on regular Shell gasoline; the other set was fueled with Shell gas blended with Virent's biogas. When the engines were dismantled and inspected after the trial, all 10 cars were in the same condition. That means Virent's biogas, made from plant sugars instead of crude oil, caused no harm.