[2] Kovalchuk began working at the age of 14 in the district department of public education, where he was involved in the development and support of software for payroll calculations and the accounting of low-value and fast-moving items.
[3] In the early 2000s, Kovalchuk's activities were related to real estate, woodworking, furniture, building materials, and work in state enterprises, where he was involved in analysis and reform efforts.
As a result of this corporate governance reform, strategic oversight of the state enterprise's activities was carried out through a supervisory board.
[11] This allowed the company to implement international standards for information disclosure and maximum transparency in the construction of energy infrastructure facilities.
[12] In 2017, Kovalchuk introduced a "single window" for submitting documents for the connection of green energy generation facilities to Ukrenergo's networks.
[13] Overall, from 2015 to 2017, thanks to the active fight against corruption in state procurement, Ukrenergo saved more than 8 billion UAH,[13] reducing equipment and work prices by an average of 40%.
[19] In November 2017, Ukrenergo approved a plan of actions for synchronizing Ukraine's power system with the European energy network until 2023.
[21] Ukraine's dependence on the Russian power system, with which it was synchronized at the time, is eliminated, enhancing the country's energy security.
In May 2019, Susanne Nies, managing director for Strategy and Communications at ENTSO-E, acknowledged significant progress in cooperation with Ukrenergo.