Touring the Metro Transit Authority in North Houston
Sometimes garnering the cooperation of professionals in the industry can be difficult. So we were delighted when the Superintendent of Fallbrook Bus Maintenance (Houston Metro), Mr. Jeff Long, graciously agreed to personally lead us on a guided tour of the newest Metro facility that already houses the first of the new Xcelsior 40’ CNG powered transit buses. Metro recently purchased 256 buses such as these. This was our chance to get a first-hand look at the support operations and the latest natural gas propelled buses; these had yet to be put into service.
The unassuming white, cinderblock complex seemed fairly ordinary until Jeff began to enlighten us to the intricacies involved in the successful operation of a mass transit system serving a greater metropolitan area of more than 2 million residents. A very tight schedule must be maintained in order to maintain punctual completion of the designated routes. That being the case, we were on a short timetable ourselves.
After a short introduction, Mr. Long entertained preliminary questions before we embarked upon our journey. The bulk of our curiosity focused on the new CNG fleet, naturally. The “useful life” of the Xcelsior buses is approximately 12 years or 500,000 miles, which is a common benchmark among transit vehicles. They have an operational range of 500 miles, which is much more than they should ever require because none of their routes exceed 200 miles. The Xcelsior’s maximum fuel capacity is 140 DGE (diesel gallon equivalent), but the buses are normally refilled to about 100 DGE. This is more than enough natural gas to complete any of Metro’s routes and the process only takes ten minutes. Counterintuitively, the buses actually see a growth in their fuel economy during the first 50,000 miles as the seals seat and the drive train is “broken-in”.
The Superintendent led us out of his office and down the hall towards the pits, where large trenches in the shop floor allow the mechanics and other service technicians to diagnose and repair the buses with the convenience of being able to stand fully erect underneath the vehicle. Here he pointed out the multiple safety mechanisms that could detect the slightest LNG (this was previously a LNG facility) or hydrocarbon leaks, as well as a fire detection, suppression, and isolation system that functioned automatically with several backup systems; the last of which being a very large thermostat coil that, after crossing a temperature threshold, will unwind, setting in motion a sequence of events, involving pulleys and cables, that slams shut a series of fire doors and shutters that would prevent a fire from spreading to other parts of the building. Not that CNG is dangerous compared to other fuels, on the contrary. CNG has a much lower risk of failure than diesel.
Moving out of the pits out to the storage lot where the CNG buses were stored until the order was to be officially received. For some reason I was chagrinned when the inside of the brand new buses had the same “new car smell” that accompanies private vehicles as well. He pointed out the slight, but very obvious, differences between diesel and CNG buses. Such as the fuel tank being on the top of the vehicle instead of the bottom due to the tendency of gas to rise and of diesel to fall. They are also fitted with dozens of gas detectors and a fire suppression system throughout the cabin. Opening the hood, which is on the back of the bus, he explained to us that CNG engines have all of the same basic parts as the diesel engines. The main difference being that CNG utilizes spark plugs for combustion of the fuel while diesel uses compression.
Eager to pose questions to someone with the experience of operating one of these machines, we queried about the driving characteristics of the CNG buses that differentiated them from their diesel propelled counterparts. In general, his drivers agreed that the CNG buses were quicker but had a slight throttle lag by comparison. Also, the consensus was that the CNG vehicles handled better, this could be due to the weight difference (CNG buses are lighter than diesel buses).
Realizing that our time with him was coming to a conclusion, Mr. Long fielded a few more questions. More than any specifications or facts, we wanted to know his overall opinion of the CNG buses juxtaposed with their diesel cousins. Although he admitted that the decision to make such an investment in CNG (Metro just purchased 150 natural gas powered buses) was “above his pay grade”, he assured us that he would have made the same choice, describing himself as “a big proponent of CNG”. The greatest advantage natural gas has over diesel, in his estimation, was that it was a domestically produced fuel that would lead to more American jobs and energy independence.
All the specifications and figures could never have given us the understanding of CNG operations that we gathered on our tour and we all left feeling as though we had a better grasp on the technology as a whole.
Click on the photos for more information!
Sometimes garnering the cooperation of professionals in the industry can be difficult. So we were delighted when the Superintendent of Fallbrook Bus Maintenance (Houston Metro), Mr. Jeff Long, graciously agreed to personally lead us on a guided tour of the newest Metro facility that already houses the first of the new Xcelsior 40’ CNG powered transit buses. Metro recently purchased 256 buses such as these. This was our chance to get a first-hand look at the support operations and the latest natural gas propelled buses; these had yet to be put into service.
The unassuming white, cinderblock complex seemed fairly ordinary until Jeff began to enlighten us to the intricacies involved in the successful operation of a mass transit system serving a greater metropolitan area of more than 2 million residents. A very tight schedule must be maintained in order to maintain punctual completion of the designated routes. That being the case, we were on a short timetable ourselves.
After a short introduction, Mr. Long entertained preliminary questions before we embarked upon our journey. The bulk of our curiosity focused on the new CNG fleet, naturally. The “useful life” of the Xcelsior buses is approximately 12 years or 500,000 miles, which is a common benchmark among transit vehicles. They have an operational range of 500 miles, which is much more than they should ever require because none of their routes exceed 200 miles. The Xcelsior’s maximum fuel capacity is 140 DGE (diesel gallon equivalent), but the buses are normally refilled to about 100 DGE. This is more than enough natural gas to complete any of Metro’s routes and the process only takes ten minutes. Counterintuitively, the buses actually see a growth in their fuel economy during the first 50,000 miles as the seals seat and the drive train is “broken-in”.
The Superintendent led us out of his office and down the hall towards the pits, where large trenches in the shop floor allow the mechanics and other service technicians to diagnose and repair the buses with the convenience of being able to stand fully erect underneath the vehicle. Here he pointed out the multiple safety mechanisms that could detect the slightest LNG (this was previously a LNG facility) or hydrocarbon leaks, as well as a fire detection, suppression, and isolation system that functioned automatically with several backup systems; the last of which being a very large thermostat coil that, after crossing a temperature threshold, will unwind, setting in motion a sequence of events, involving pulleys and cables, that slams shut a series of fire doors and shutters that would prevent a fire from spreading to other parts of the building. Not that CNG is dangerous compared to other fuels, on the contrary. CNG has a much lower risk of failure than diesel.
Moving out of the pits out to the storage lot where the CNG buses were stored until the order was to be officially received. For some reason I was chagrinned when the inside of the brand new buses had the same “new car smell” that accompanies private vehicles as well. He pointed out the slight, but very obvious, differences between diesel and CNG buses. Such as the fuel tank being on the top of the vehicle instead of the bottom due to the tendency of gas to rise and of diesel to fall. They are also fitted with dozens of gas detectors and a fire suppression system throughout the cabin. Opening the hood, which is on the back of the bus, he explained to us that CNG engines have all of the same basic parts as the diesel engines. The main difference being that CNG utilizes spark plugs for combustion of the fuel while diesel uses compression.
Eager to pose questions to someone with the experience of operating one of these machines, we queried about the driving characteristics of the CNG buses that differentiated them from their diesel propelled counterparts. In general, his drivers agreed that the CNG buses were quicker but had a slight throttle lag by comparison. Also, the consensus was that the CNG vehicles handled better, this could be due to the weight difference (CNG buses are lighter than diesel buses).
Realizing that our time with him was coming to a conclusion, Mr. Long fielded a few more questions. More than any specifications or facts, we wanted to know his overall opinion of the CNG buses juxtaposed with their diesel cousins. Although he admitted that the decision to make such an investment in CNG (Metro just purchased 150 natural gas powered buses) was “above his pay grade”, he assured us that he would have made the same choice, describing himself as “a big proponent of CNG”. The greatest advantage natural gas has over diesel, in his estimation, was that it was a domestically produced fuel that would lead to more American jobs and energy independence.
All the specifications and figures could never have given us the understanding of CNG operations that we gathered on our tour and we all left feeling as though we had a better grasp on the technology as a whole.
Click on the photos for more information!