What is the difference between PGT25+G4 DLE & PGT25+G4 SAC engines?

 

This was the first result found using my preferred World Wide Web search engine and the search term: PGT25+G4

https://www.geoilandgas.com/sites/geog/files/pgt25g4-aeroderivative-gas-turbine-flyer.pdf

DLE stands for Dry Low Emissions, and it's the aero-derivative version of DLN (Dry Low NOx). It includes additional fuel control valves, and I think the combustors are multi-zone (at least they were in the early days of development).

SAC stands for Single Annular Combustor, and it's usually a simple, single annular combustor with one combustion zone. To achieve low NOx emissions it's usually necessary to use water- or steam injection (which adds somewhat to the complexity of the auxiliaries).

Other than that, I believe they are basically the same engine--one has the DLE combustion system for low emissions without water- or steam injection (at least for gas fuel), and the other is a "plain" combustion system which must use water- or steam injection for low emissions.

Hope this helps!

By the way, I also found this site (which I personally hadn't run across before):

https://etn.global/about-etn/gas-turbine-technology/gas-turbine-products

Looks like a good way to quickly compare lots of different products for lots of different manufacturers.

 

Yup. Basically the same engine turbomachinery except for the combustor. The combustor difference drives a significant difference in the fuel system. A standard gas only G4 SAC engine will have 1 metering valve. A standard gas only G4 DLE will have 5 metering valves. All the added complexity in the DLE fuel system is designed to achieve lower emissions.

Also, a +G4 core can be mated with several different power turbines. Baker Hughes typically refers to a +G4 with their high speed power turbine (HSPT) as a PGT25+G4. The nominal speed for the PGT25 is 6100 rpm and is used most often in mechanical drive applications.

When Baker Hughes mates a +G4 core with a GE low speed power turbine (LSPT) they refer to it as an LM2500+G4. A low speed power turbine is typically use in power gen applications and so it spins at either 3000 rpm or 3600rpm as needed for the grid.