Green Goat Gives Diesel Trains A Serious Head Butt

TH_greengoatmain_050805.jpg While a huge part of the global economy runs on commercial trucking, a substantial percentage is still taken care of by railways. One of the major benefits of a rail-style system is that once you get the freight moving, it stays moving. This minimal stopping means high efficiency for the engines responsible for pushing the cars cross-country. But in the freight yards where loads of freight have to be shuttled around to change tracks, the cars stop and start a lot. With tens of thousands of pounds of freight being pushed around, that can mean huge energy losses for the "Goats" -- the freight tug engines which do the pushing. Luckily, a Canadian company has an answer to this problem: Brawn and Batteries...Railpower Technology has rolled out a new Diesel-electric hybrid engine. Dubbed the Green Goat, this burly little fella is set to shake things up in the rail yard.

Diesel Electric isn't new for trains. Most Diesels on the tracks today actually run a generator with their fuel, and use that electricity to drive the wheels. The problem is starting up: If you think your little Corolla has trouble getting up to speed in first gear, imagine what a starting hundreds of thousands of pounds of freight moving would be like. You'd wear through a transmission a week. Instead, using electricity allows the motors to run at a constant gear ratio, and speed is controlled by varying power to them.

But even so, these trains suffer from huge losses because the large diesel engines needed to deliver the starting power (up to 3500 horsepower!) are kept on even when the power needs are nowhere near this level. This idling engine loss leads to massive amounts of fuel being burned unnecessarily.

The Green Goat substitutes a much smaller 250hp engine-generator setup, but also adds storage batteries capable of 2000hp for high-power starting. After the generator is no longer needed, it simply shuts off, eliminating idling losses. The train can then run off power from the battery banks.

This hybrid setup creates almost unbelievable advantages:

- Improved visibility because of lower generator housing.
- Improved traction, because of heavy weight of batteries.
- 80-90% reduction in NOX and Particulate emissions.
- 30-80% fuel savings
- First year is virtually maintenance free, and subsequent upkeep is simple because of small, light, standard parts
- Smaller generator makes operation very quiet

With tens of thousands of switching locomotives around the world, the introduction of the Green Goat could mean serious fuel savings, and cleaner air.
:: Railpower's Green Goat [by DM]



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