Name of the Project
Koeberg nuclear power station steam-generator replacement (SGR) project.

Location
Western Cape, South Africa.

Project Owner/s
Eskom.

Project Description
The current steam generators in Unit 1 and Unit 2 have been in operation since 1984 and 1985 respectively. The aim of the project is to extend the design life of the Koeberg nuclear power station by 20 years to 2045.

The project involves the replacement of all six steam generators for units 1 and 2.

The SGR project  involves the design, manufacture and installation of three steam generators in each of the Koeberg power plant’s two operating units, as well as safety analyses and studies to comprehensively demonstrate the plant design integrity, with no adverse impact on public and worker safety and health or the environment, including the enhancement of nuclear safety.

The new generators will incorporate modern design features for easy maintenance and inspections, and improve heat-transfer efficiency, leading to an overall efficiency improvement of Koeberg.

The installation of the generators will be conducted during the scheduled refuelling, inspections and maintenance outages of the two units at the power station. Eskom is on track and progressing according to plan for installation during the next unit 1 and 2 outages.

The other major components of the life-extension plan include:

a refuelling water storage tank replacement project, which was completed in 2019;

the Unit 2 reactor pressure vessel head replacement, for which manufacturing is scheduled for completion in 2021 and the installation thereof for 2022;

the replacement of feed-train components on the conventional power plant, which is conducted during maintenance outages; and

the ongoing Koeberg safety aspects of long-term operation assessment. The assessment is designed to provide the equipment-ageing management confirmation to enable Koeberg  to operate beyond the original 40 years life span to at least 60 years.

This safety case on the life extension will be presented to the National Nuclear Regulator in mid-2022 to allow for approval of the Koeberg plant’s entering into long-term operation from mid-2024.

Capital Expenditure
Not stated.

Planned Start/End Date
Work on replacing the steam generators for the first of Koeberg’s two units is scheduled to start during a planned outage in January 2022, with the overall project taking two years to complete.

Latest Developments
Unit 2 of the Koeberg nuclear power station was taken offline on January 17 for refuelling and a five-month maintenance outage, which may strain overall electricity supply in the country.

Consequently, the unit’s three steam generators being replaced. The reactor pressure vessel head will also be replaced, with Eskom reporting that this will be a first for the plant.

Prior to the maintenance outage, Unit 2 had been operating uninterruptedly for 452 days since its last refuelling outage in October 2020.

A similar maintenance outage is scheduled for Koeberg Unit 1 later in the year, during which its steam generators will also be replaced. 

Eskom has said that, although the maintenance outages are planned at times of the year when the impact on the overall electricity supply is minimised as much as possible, the extended unavailability of the units may place additional strain on the grid.

“Nuclear safety is the paramount factor. We will progress the outage work diligently, making sure nuclear safety and safety of plant, personnel and public is top of mind,” Eskom chief nuclear officer Riedewaan Bakardien has said.

The equipment replacement is a precautionary safety measure and key to extending the life of the plant.

The successful replacement of the steam generators and reactor pressure vessel head is an important element of the safety submission being prepared for the National Nuclear Regulator in mid-2022, in support of extending Koeberg’s operations for 20 more years.

Key Contracts, Suppliers and Consultants
Framatome (main SGR contractor); General Electric (modifications to the balance of plant or secondary turbine system); and Jacobs Engineering (BoP hardware changes).
 
Contact Details for Project Information
Eskom media desk, email mediadesk@eskom.co.za.