Uniper JV Builds Swedish Test Reactor in State Nuclear Push

(Bloomberg) -- A venture between Uniper SE and Sweden’s Blykalla AB has started work on a test reactor, the latest sign that the nation’s nuclear renaissance is gathering pace.

The small plant on the site of Uniper’s Oskarshamn atomic power station will be Sweden’s first new reactor in about 40 years. With electricity demand poised to surge in coming decades, the government sees the controversial technology as one of the main answers to boost supplies.

The unit won’t produce any power and won’t be loaded with nuclear fuel. Instead, the purpose is to shine a light on various processes, including safety features, that will be applied to a lead-cooled version of a small modular reactor — or SMR — that Blykalla is designing.

Uniper’s move comes even after executives repeatedly ruled out investing in new Swedish atomic plants. It’s motivated more by a need to further research and development of SMR technology, according to the company, which is currently owned by the German state. For Sweden, the test reactor is a step toward meeting a key 2022 election pledge for new nuclear.

“It’s a milestone for our company, and also a milestone for Sweden,” Blykalla Chief Executive Officer Jacob Stedman said in an interview. The facility will be ready by this summer, with tests set to commence in the third quarter, he said.

The plant is being built by Swedish Modular Reactors AB — a 50-50 joint venture between the German power giant and Blykalla. 

The firm aims to submit an application for the SMR in about a year’s time, Stedman said. It could then be up and running at the turn of the decade. 

The first nuclear SMR would have a capacity of about 70 megawatts. That’s much smaller than the nation’s six existing reactors, which are all above 1,000 megawatts. The next stage would be a series of 140-megawatt units. 

Blykalla has so far raised about 300 million Swedish kronor ($27 million) for the test reactor, including 100 million from the state, Stedman said. The firm will continue to raise funds this year.

Sweden’s center-right coalition is going all in with a goal to have several new reactors online by the middle of the next decade. The government expects power demand to double to about 300 terawatt-hours by around 2045.

But it’s a huge gamble, given how technologies such as solar and wind continue to get cheaper, and critics argue that energy storage and other rapidly developing technologies could balance weather-dependent power sources.

“The challenge with new nuclear is that it takes a very long time to build and historically it’s been extremely expensive,” Stedman said. “But with our SMRs, we have a solution that will be much cheaper and quicker.”

Uniper operates the Oskarshamn-3 reactor and also has stakes in other Swedish atomic units. 

“We entered the partnership to help boost the SMR technology and the possibilities it offers for new nuclear capacity, but more to stimulate research and development, which is something we need also for the existing assets,” Swedish head Johan Svenningsson said in an interview. 

(Updates with power demand in 10th paragraph. An earlier version corrected the timing for new reactors.)

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