Gas Turbine Performance Recovery Advisor


Thread Starter


Dear all,

We have 6 gas turbines (9FA) and 3 steam turbines (GE D11). advice from OEM is to install the Gas turbine performance recovery adivsor at our site which will suggest when to do offline wash and inlet air filter replacement. It projects the optimal timing based on the FFH. But it deals to lot of amount of money and few times it may not be possible to do the washing at the recommended intervals either due to grid demand or to meet some other economical factors.

Please share your views. whether it is suggestible to install this software at our site. what are the pros and cons, etc.?

the GE performance monitoring package is very expensive, but good. It pretty well depends on what your needs are. You can do it yourself by running your machine, preferably at Base Load once a month or every two months. What you need to do is set up a spreadsheet in Excel, enter the data and convert to ISO conditions. You can find the conversion graphs in your GE manuals, usually in Vol. 1. If that is good enough for you, it is pretty easy to. It well lets you predict when you need to do Offline washes, and gives you good idea of the condition of your machine

Write back to us and let us know what you think.

I don't have experience in using that software. But in our site we are not using any software to determine offline WW and air inlet filter replacement. Offline WW is required when your turbine performance is very low at the base load. You can see some parameter such as MW and CPD. Also with air inlet filter replacement, you can see at DP air inlet transmitter. but you can also determine the lifetime of filter from filter manufacturer (Usually GE use Donaldson). with that data you can make preventive schedule for replacing air inlet filter.

So basically with parameter data that you get from HMI you can monitor the trend and make your own decision.

Hope this help.


Dear Sir,

Thank you very much for the feed back. Yeah we do feel its very expensive and does not make much more sense. Actually at our site we are practicing the offline wash when accumulated FFH crossed more than 2200 hours (again this time we are monitoring the MW and CPD also, before proceeding for wash and also grid availability etc) however not more than 2 times we are doing the wash in a year and mostly we are doing it during the offload season (winter time) etc.

Please clarify, whether our practice is right or wrong. we are conducting a test before proceeding for the offline wash and comparing the data set after the offline wash. but the question for me does the ambient conditions will make any difference in comparing the compressor efficiency. we have compressor efficiency trending using the formula based on ctd, cpd, atmospheric pressure and Ctim, but the isentrpoic efficiency is considering GAmma = 1.4. but does this trending give exact view????

When the Air inlet filter DP (IPDP) reaching the alarm limit based on the grid low load availability we are shutting down the unit and cleaning the inlet filters.(as we have 6 machines normally we are not declaring the machine is not available to the grid like that, if grid is asking more dispatch we are accommodating it with other standby machines), so dont have much issues for cleaning the filter and coalscer pads when it reaches alarm level except during summer season.

If you don't understand my context please let me know i will try explain a bit more clear.

However my present interest is if any one of the experts having any calculations sheet or trending formulas when to do offline wash exactly (condition based maintenance) and when to replace air inlet filters cost effectively, please share that would be great help. My mail address is [email protected]

We have PI historian computers so we can have the ready available data from Historian.

Sir if you have spreadsheet in excel to determine it please share. that would be great help.

Happy to share whatever the information you requires.

basically we are not interested in taking this software as it involves lot of initial capital and also requires annual maintenance fees.