**2. Energy efficiency and reliability**

Improving energy efficiency and reliability goes in several ways. Some of the solutions are to continuously monitor and supervise vital equipment in power plants, like generator trans‐ formers, in order to improve maintenance and reduce costs. Additional advantage is deci‐ sion support, where results taken from online monitoring systems are analyzed by external experts that help plant staff and management to make decision about plant operation when

some of the possible malfunction of transformers is detected or expected [4]. This also could yield to proper time schedule of transformer replacement [5].

Modern control systems in power plants cannot be realized without the modern system of monitoring of process parameters or parameters of machines and systems. Continuous moni‐ toring includes continuous monitoring of machine operation (online), automatic storage of information and the possibility of automatic or subsequent processing and analysis. It also includes the generation of specific alarms and their submission to the operator and control system, according to a certain procedure [6]. Diagnostics of the generator are based on a wide range of data from off‐line and online testing generators and data analysis. All test data, oper‐ ating data and data of the machine are stored in a database for generators. Thus, all test data from any laboratory, repairs, unexpected events and failures are available for analysis. The data in the database with each successive inspection and testing are updated. The database is very flexible and has the ability to expand for all possible new types of tests, acquisition of photo records of visual inspections and so on [7].
