inicioir al DIIbuscar
compressed natural gas (cng) sweeper operation evaluation

Several counties across California have begun to switch from diesel-powered street sweepers to CNG (Compressed Natural Gas) street sweepers, in order to comply with Federal and State air quality regulations.  We studied the productivity and cost impact of using CNG sweepers as opposed to the diesel sweepers. On balance, the move to CNG sweepers has resulted in a reduction in the productivity of sweeping operations. One key problem with the CNG sweepers is that the CNG fueling stations might be located far from the yard and the waiting time at the fueling station may be long.  To offset this loss in productivity with CNG sweepers, we developed mathematical optimization models to make specific recommendations regarding (1) the locations where Caltrans should promote the use of CNG fueling stations, and (2) the rebalancing of the routes.