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Re: Of the 385,000 electric buses worldwide, 99% of them are in China
Author: yep
Date: 12-29-2018 - 18:51
Just check the CHP logs at random: [cad.chp.ca.gov]
Practically every day, there's a "car fire" (often a truck fire) that ties up traffic in the Bay Area or LA. They're a standard occurrence on steep grades like Grapevine - truck brakes get overheated, set the tires on fire, which sets the trailer and/or cab on fire. Awful lot of fires simply starting under the hood of trucks. And it seems like at least 10% of overturn accidents end up with a fire. None of those are electrics.
I would echo the point about trolley buses with auxiliary batteries and their weight advantage. That not only makes them more efficient overall, it also makes them better at climbing hills - a useful trait in SF. And coming back down the hill, if a battery bus fills up the battery it has no more regenerative braking (unless dynamic brake grids are added - more complication and maintenance issues), resulting in brake overload and the potential for fire from that; a trolley bus can feed the regenerated power back into the line once the battery is recharged. The hybrid buses currently used in SF are electric assist for the diesel, not straight electric, and on descent the engine can assist with braking (as is also done in hybrid cars like the Prius once the battery reaches full charge).
Amusing side note: the fanatics are all rah rah about plug-in hybrids, with a large battery and the ability to operate electric-only with reasonable (if not full) performance for some distance (typically 20-40 miles) after a charge from the grid. That can be good, if normal trips are within the electric range so little or no fuel is burned. The downside, compared with a "normal" non-plugin hybrid version of the same car, is that the battery weight reduces useful load (uses up part of the GVWR) and reduces gas mileage when running with the engine after the initial charge runs down. Check out the Prius vs. Prius Prime EPA ratings. The difference isn't big, but it's there. Really, it's better to use two vehicles, with one all-electric for running around town and the other non-plugin hybrid for longer-range use, if you're trying to maximize fleet fuel economy.
One question not yet clearly answered: are there battery-powered rail transit vehicles in use that are as practical as trolley-battery buses? Any record of their performance in the field, and their cost to purchase and operate?
Practically every day, there's a "car fire" (often a truck fire) that ties up traffic in the Bay Area or LA. They're a standard occurrence on steep grades like Grapevine - truck brakes get overheated, set the tires on fire, which sets the trailer and/or cab on fire. Awful lot of fires simply starting under the hood of trucks. And it seems like at least 10% of overturn accidents end up with a fire. None of those are electrics.
I would echo the point about trolley buses with auxiliary batteries and their weight advantage. That not only makes them more efficient overall, it also makes them better at climbing hills - a useful trait in SF. And coming back down the hill, if a battery bus fills up the battery it has no more regenerative braking (unless dynamic brake grids are added - more complication and maintenance issues), resulting in brake overload and the potential for fire from that; a trolley bus can feed the regenerated power back into the line once the battery is recharged. The hybrid buses currently used in SF are electric assist for the diesel, not straight electric, and on descent the engine can assist with braking (as is also done in hybrid cars like the Prius once the battery reaches full charge).
Amusing side note: the fanatics are all rah rah about plug-in hybrids, with a large battery and the ability to operate electric-only with reasonable (if not full) performance for some distance (typically 20-40 miles) after a charge from the grid. That can be good, if normal trips are within the electric range so little or no fuel is burned. The downside, compared with a "normal" non-plugin hybrid version of the same car, is that the battery weight reduces useful load (uses up part of the GVWR) and reduces gas mileage when running with the engine after the initial charge runs down. Check out the Prius vs. Prius Prime EPA ratings. The difference isn't big, but it's there. Really, it's better to use two vehicles, with one all-electric for running around town and the other non-plugin hybrid for longer-range use, if you're trying to maximize fleet fuel economy.
One question not yet clearly answered: are there battery-powered rail transit vehicles in use that are as practical as trolley-battery buses? Any record of their performance in the field, and their cost to purchase and operate?
