Fortum eNext and operators of Forsmark and Ringhals nuclear power plants enter into a service agreement to guarantee availability of nuclear power in Sweden

14 June 2021, 15:51 EEST

Fortum eNext has agreed with Forsmarks Kraftgrupp AB and Ringhals AB on five years’ availability of Fortum’s balancing facility to ensure competent maintenance of the special water-cooled rotors on short notice.

A generator rotor in balancing at Fortum eNext's high speed balancing bunker in Västerås, Sweden.

Forsmark and Ringhals are nuclear power plants in Sweden operated by Forsmarks Kraftgrupp AB and Ringhals AB, both mainly owned by Vattenfall, a major producer of nuclear power in northern Europe. In 2020, nuclear generation represented around 30% of Sweden’s electricity production. In order to maintain the units’ high availability, the operators partnered with Fortum eNext to secure qualified repairs nearby and balancing for a total of 8 generators at Forsmark units 1 and 2 and at Ringhals units 3 and 4.

The reactors at Forsmark and Ringhals are a special type of boiling water reactor designed by Asea-Atom, and the generators are based on the original ASEA design with water-cooled rotors. Fortum eNext is the only independent service provider in the Nordics to provide the knowhow and the balancing facility with water needed to service this type of rotor. Fortum’s two balancing units are located in one single facility in Västerås, Sweden. The smaller unit balances rotors from 1,300 kg to 30,000 kg and the larger from 30,000 kg to 110,000 kg. An adjoining engineering office and workshop houses repair and modernisation operations.

The agreement covers five years’ availability of the balancing bunker with option to prolong it, as well as modernisation of the balancing facility and special equipment to provide cooling-water to the rotor and enabling electrical measurements of the rotor at operational speed. The agreement also includes regular training of the workshop’s staff. The operators will provide a rotor for training purposes, and once a year the rotor will be taken out and re-installed; twice a year Fortum will run and balance the rotor.

From the risk management point of view, the significance of having a local competent service provider has become even more evident during the Covid-19 pandemic. Maintaining the competence is equally in both parties’ interest.

“This is a true win-win case. With this deal the operators of Forsmark and Ringhals ensure access to a service provider in Sweden, a provider who is able to make repairs of the rotor and balance it with water-cooling on short notice. We are very pleased to be able to offer this service to them. Moreover, this gives us the opportunity to maintain and develop our knowhow on this very special water-cooled type rotor for nuclear applications,” says Senior Product Manager Gabor Csaba from Fortum eNext.

In April 2020, we told about a deal to service and balance the Forsmark FRR2 water-cooled rotor.

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