Marker blog
Posted by admin at 6:51PM on 5/25/2011 with tags: , , , ,

Source: City of Palm Desert

The city of Palm Desert, Calif. (in Riverside County), announced this week that they plan to convert a retrofitted CNG-powered ambulance back to diesel, after the vehicle failed to meet expectations.

“The ambulance, which was unveiled by the city in January 2010, only put out 82 miles per tank, well below the mandated average of 250 miles in Riverside County, according to Capt. Scott Visyak of the Riverside County Fire Department, which contracts with Palm Desert for its firefighting services.”

 

Range is one of the biggest obstacles for natural gas vehicles, as it must be compressed at up to 3600 psi in bulky, heavy tanks. According to a 2010 Department of Energy study titled “Issues Affecting Adoption of Natural Gas Fuel in Light- and Heavy-Duty Vehicles,” the most common type of CNG tank occupies 3 times the volume and weighs “4 to 5 times as much” as a same-capacity gas tank. Therefore, lower gallon-equivalent-capacity causes a reduced driving range.

The failed experiment came with no small price tag. “The ambulance initially cost the city $186,000 to convert the emergency vehicle, according to the city.”

Fortunately, the city won’t have to pay quite that much to convert the vehicle back to diesel. One month and another $78,000 later, they’ll have a regular ambulance again.