chris kennedy
Senior Member
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- Miami Fla.
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- 60 yr old tool twisting electrician
Saturn_Europa said:
Anyone have anymore info on this? Genny size, motor type?
Thanks
Cat genny issues?
- Thread starter chris kennedy
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Anyone have anymore info on this? Genny size, motor type?
Thanks
kwired
Electron manager
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- NE Nebraska
I read the thread you got that from. The issue there has to do with newer diesel emissions laws. I don't know all the details of how how emissions are being controlled but understand a diesel engine that is not loaded has higher level of emissions problems then one that is loaded, the exhaust gases are not hot enough for the emissions cleanup devices to be as effective, so if you have prolonged limited load periods you will have performance issues compared to if you were constantly running at a higher load.
I know when some of the new trucks first came out that had to comply with these emissions laws, if they sat there idling for long periods of time the emissions cleanup devices essentially become plugged, you lose output power ability because of it, and are going to sit there for some time with engine revved up to a high speed to burn off the contaminants before you gain sufficient output power again.
Sitting there at idle or maybe even at high speed but limited load will likely be a problem over enough time. I can see this being an even bigger issue for off road uses where a diesel powered machine maybe isn't always used at a high load level.
JFletcher
Senior Member
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- Williamsburg, VA
Sounds like wet sumping and it isnt limited to Cats.
If I may on Saturn Europa's problem: gensets for WW plants are beasts, and they are usually designed for one thing: running the complete plant off grid. Yes, I know about paralleling them with POCO power to peak shave; at least the design goals. In practice, such a light loading causes the gensets to run far below what they are designed to do, they dont heat up to proper operating temps, and you have more problems than if you run them full song (at capacity). Those problems are high oil consumption, higher emissions, high fuel consumption relative to power, and increased maintenance. It is not cost efficient to run on internal power for any amount of time, for any reason. You do it because you have to maintain treatment.
I was at Nansemond plant when they got their twin Cat gensets, a massive improvement over the gas turbine that was there. Problem was the plant had vastly different power needs based on one thing: being able to gravity flow to the outfall. Normally, you can, and you dont need the (up to) 3 700HP final effluent pumps. But the gensets are sized to run the entire plant off grid, and pump that water against gravity, say like when a hurricane causes gravity outfall to become impossible due to storm surge. 1 Generator cannot run the entire plant, and 2 is massive overkill for all but the rarest condition (power loss during a monster hurricane).
Operationally, is it easier to reduce electrical loads by shifting anything that would be a batch operation to off-peak hours, than run a generator trying to reduce power costs.
They also had an 800HP gas driven aeration blower designed to run on digester gas. It's so massively oversized to gas production that it sits there, a very expensive toy, something some engineer thought a great idea (and it is), but grossly hosed up on the calculations.
Chris, probably 12-16cyl Cats in the 1MW range, tho I dont know SE's plant size
If I may on Saturn Europa's problem: gensets for WW plants are beasts, and they are usually designed for one thing: running the complete plant off grid. Yes, I know about paralleling them with POCO power to peak shave; at least the design goals. In practice, such a light loading causes the gensets to run far below what they are designed to do, they dont heat up to proper operating temps, and you have more problems than if you run them full song (at capacity). Those problems are high oil consumption, higher emissions, high fuel consumption relative to power, and increased maintenance. It is not cost efficient to run on internal power for any amount of time, for any reason. You do it because you have to maintain treatment.
I was at Nansemond plant when they got their twin Cat gensets, a massive improvement over the gas turbine that was there. Problem was the plant had vastly different power needs based on one thing: being able to gravity flow to the outfall. Normally, you can, and you dont need the (up to) 3 700HP final effluent pumps. But the gensets are sized to run the entire plant off grid, and pump that water against gravity, say like when a hurricane causes gravity outfall to become impossible due to storm surge. 1 Generator cannot run the entire plant, and 2 is massive overkill for all but the rarest condition (power loss during a monster hurricane).
Operationally, is it easier to reduce electrical loads by shifting anything that would be a batch operation to off-peak hours, than run a generator trying to reduce power costs.
They also had an 800HP gas driven aeration blower designed to run on digester gas. It's so massively oversized to gas production that it sits there, a very expensive toy, something some engineer thought a great idea (and it is), but grossly hosed up on the calculations.
Chris, probably 12-16cyl Cats in the 1MW range, tho I dont know SE's plant size
chris kennedy
Senior Member
- Location
- Miami Fla.
- Occupation
- 60 yr old tool twisting electrician
Yeah, thats why I asked. I deal with many and hadn't heard of this issue.
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