The Rehabilitation

Any type of hydrotechnical structure needs overhaul in every 20-25 years. The structures of Enguri HPP, depending on their complexity and parameters, need to be repaired in every 10-15 years. As for the units and the transformers, the term of overhaul is even less. In the reality Enguri HPP appeared in, it was not possible to provide full-scale maintenance for 20 years. Therefore, by the end of the 1990s, most of the technical components of the enterprise required overhaul. However, financing from the budget was impossible due to the serious economic problems at that time. Even ongoing repairs failed over the years, instead of scheduled overhauls at the plant. This means that all the small and large equipment, that needed replacement or repair, could not be replaced or repaired.

Of course, preservation of Enguri HPP in a condition where it could generate even minimum electricity is the merit of the technical staff who were able to do all kinds of repair work on their own. Despite of the fact that in the 90s, the enterprise did not receive even the minimum required funds and therefore, it was not possible to buy spare parts either, the units worked and Enguri HPP provided vital electricity for the country. However, the technical condition of both buildings and equipment was gradually deteriorating. That's why since the beginning of the 2000s, we have reached the stage that Enguri HPP was practically shut down and needed urgent rehabilitation.

The study of the facility in this direction began in the late 1990s. By that time, one out of five units no longer existed in fact. In particular, an empty pit was left at the site of the third unit. The large-scale rehabilitation project of the Enguri HPP was developed in 1998-2001. Major rehabilitation works were carried out in 2003-2014 with the support of the Government of Georgia and the European Bank for Reconstruction and Development (EBRD).

What does the Enguri HPP rehabilitation project mean? 

If the technical equipment do not undergo timely maintenance and overhaul, they will automatically appear in such a technical state where they need not overhaul any more, but a larger procedure called rehabilitation or restoration. The same happened with the third unit. Accordingly, the rehabilitation project started, because it could no longer be considered as overhaul or other type of work. The rehabilitation project included immediate and urgent technical operations, which were directly related to generation of electricity. For example, this applied to units, transformers, turbines, etc. This was necessary for putting Enguri HPP into more or less output mode as quickly as possible. 

Depending on the scale of the project, the rehabilitation would cover the period of 15-20 years from the beginning. Fulfillment of similar works at the same time was even theoretically impossible. Therefore, it had to be written in phases and it happened. The first phase lasted from 2003 to 2009. It was at this time that three units were rehabilitated, while the rest of the electrical equipment was repaired. In addition, together with rehabilitation of Enguri HPP dam and derivation tunnel, other important works were carried out in 2006. Accordingly, three phases of rehabilitation were completed in 2015, and the fourth phase began in 2016, however certain works were added in 2020-2021. As a result of all these efforts, we got the fact that Enguri HPP and Vardnili HPP-I are working perfectly today. 
 
When will Enguri HPP rehabilitation be completed?

The final stage of the fourth phase of rehabilitation of Enguri HPP includes works to be performed in 2024-2027. Based on technical safety and priorities, technical stability, ensuring seismic stability and completion of diversion tunnel works are decisive in the planned process. In addition, this is the necessity of the accumulated capital works that Enguri HPP needs. This refers to replacement, adaptation, modernization, etc. of a number of electrical and hydromechanical equipment. Construction of roads is also provided here, which is necessary for safe operation and monitoring of the dam. 

According to the plan, The final stage of the fourth phase of rehabilitation should be completed in 2026-2027. If everything goes according to schedule,  Enguri HPP will not need overhaul in the next 15-20 years. Thus, after completion of the final phase of the fourth phase of rehabilitation, Enguri HPP will go into the mode of ongoing repairs, which will be its natural state.