In April 2008, McDonald's announced that 11 of its restaurants in Sheffield, England, were engaged in a biomass trial program that cut its waste and carbon footprint by half in the area. In this trial, waste from the restaurants was collected by Veolia Environmental Services and used to produce energy at a power plant. McDonald's announced plans to expand this project, although the lack of biomass power plants in the United States would prevent adoption of this plan as a national standard there anytime soon. In addition, in Europe, McDonald's has been recycling vegetable grease by converting it to fuel for its diesel trucks.