I thought this might be of interest to some of you:
http://finance.yahoo.com/news/GEs-Evolution-Series-bw-15551743.html?.v=2
Ed
I’m sure GE is enjoying it. I would maybe guess the fuel economy has to do with the 12 cylinder engine.
Without knowing any specifics of either design, I am certain that the different consumption rates are the result of myriad of very subtle design and engineering differences between the prime movers, as well as the accessories that are necessary for line of road operation.
From the outside looking in, we would like to ascribe the differences to one or two specific things…the reality always goes to dozens if not hundreds of little things, that when all added together result in a much bigger difference.
… the fact that the GEVOS have four fewer cyinders than an EMD 16-710 is def. a factor. That is a major difference…
Off of the information I have been able to find there is very little displacement difference betwee the 12 cyl EVO and the 16 cyl 710 that EMD is using
EVO 9.84 in. bore x 12.59 in. stroke x 12 cyl = 11397.87 cu.in.
710 9.02 in. bore x 11 in. stroke x 16 cyl = 11246.45 cu.in
in theory, more cubic inches should consume more fuel.
Keep in mind that the EMD has twice as many firing events as the GEVO does due to it being a two stroke engine … but as it is, that’s still pretty good. The GEVO engine has a higher top speed in RPM.
3 things are different and make the Differance in the GE over the EMD prime Movers. One is the Turbocharger arrangnement. A clutch driven turbo/supercharger is a FUEL HOG til the motor is spinning fast enough to overrunnig the clutch. Second is the Air to Air Intercooler When you cool the charge of air that is feeding the cylinders you get a more complete burn and better more efficent motors also. Lastly a 4 stroke is plain and simple more efficant over a 2 storke design. The Piston is still going down when it uncovers the intake ports and the exhaust valves open dumping out any cahnce the 710 had to catch the EVO series at all.
In addition to prime mover differences, GEVOs have more advanced electrical transmission systems. For a given engine horsepower output, GEs put a higher percentage of that power down to the rail. This also helps in overall fuel efficiency.
What are those differences? Is the 6 individual inverters vs 2 on EMD?. Or is other items and how would all these items is be a factor in electric motors?
I know GE uses a Individual metered Injecter for each Cylinder. Emd still uses a Common rail setup with a Mechaincal linkage to the Governoer. GE has had Electroncis controling the Fuel Injectioon since the Dash-9’s. When each piston gets the perfect amount of fuel not any extra makes a differance. Also there are a few other things on the EVO,s that are way out there when the computer looks at the demands from the Engineer and then the power needed from the Prime mover to decide if it needs to increase the fuel flow that is why GE loads slower put while it is doing that it is pouring the amps if possible to the TM’s
Some notes from the EMD Power Products Brochure currently on their website.
“Fuel Injectors - Electronic Unit Injectors - needle valve”
“Since EMD is the only medium speed two cycle diesel engine manufacturer in the world, we are the experts. The fact is that the EMD 710 family has been Tier 2 certified since January 2005. EMD received our EPA Tier 2 certification in May 2006. So how did we do it? Common rail fuel injection, adding another turbocharger, new electronic controls? No none of these were required,”
M636C
…that is almost meaningless in terms of BSFB (engine fuel efficiency).
It’s the engine’s BMEP (compression ratio + boost, sort of) that’s important!
All of that fancy mumbo-jumbo and they still take forever to load up. Just another bean counter loco.
Does anyone know which engine is more reliable, the SD70ACe or the GEVO? I’d be curious to see which one on average costs more to service and/or repair.
Translation: “Since we are now owned by a cheapskate investment firm, we don’t have any R&D money to update our outdated technology. However, that won’t stop our Marketing Department from trying to sell it.”
What’s a typical price for the new GE vs the EMD models?
In the GM era EMD locomotives were historicaly more expensive than GE and GE offers one stop shopping for financing as well. Many years ago EMD lost an order for 100 locomotive from Conrail because they were $1000 each higher than GE’s bid. I also heard a rumor that even even some EMD’s were financed through GE. It was about this time that GMAC broaden there market into capital goods. As far as the report on fuel consumption I noted that the test were run in presumably cold weather and if you fiddle with the cooling fan temperature control switches you can get at 6% improvement by increasing the jacket water temperature from 150 deg to 190 deg. Alright railroad guys its time to place your bets.