While catastrophic in scope, and of course in nature in more ways than one, analysts are saying that the recent oil rig fire and resulting spill in the Gulf of Mexico should not “dramatically” affect long-term supply of natural gas or oil.
While supply was trimmed after two other rigs shut down operations in response to the clean up efforts, according to a Reuters report this week, the long-term effect on the nation’s natural gas stores are expected to be minimal because the majority comes from elsewhere. But, apparently, there are other more immediate concerns for school transporters who rely on natural gas to power their school buses.
The special, very expensive vehicle fuel tanks necessary to hold CNG are good for a maximum of 15 years before they need to be replaced. That’s one reason why in 2004 the National Renewable Energy Laboratory found that propane was cheaper than CNG, even the conversion kits available for school buses at the time pale in comparison performance-wise to the newer propane engine models.
Still, the ages of CNG school bus didn’t appear to be a source much concern a few years ago when most states and school districts required school buses be retired. But that was before the Great Recession decimated budgets and forced an extension of school bus life and service.
It can all amount to hidden infrastructure costs, especially for many school districts in, say, California, where local air quality management districts fronted a lot of the cash necessary to turn fleets over to CNG. The thought for some was that these “free” buses would remain that way. But now, schools like Napa Valley Unified north of San Francisco is faced with replacing CNG fuel tanks at a cost of $25,000 per. So, according to Ralph Knight, the district’s transportation director, the cost to replace all fuel tanks in all of the CNG buses would cost more than $650,000.
Good thing for that lower cost of CNG fuel per gallon compared to diesel.
