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Algae cultivation heats households in Sweden

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Excess heat from an algae cultivation process is being used to heat homes in Gustavsberg, Sweden, as a result of a collaboration between energy company Vattenfall and AstaReal, a leading producer of natural Astaxanthin – an ingredient with applications in many sectors, including cosmetics, food and animal nutrition.

The production process behind Astaxanthin is highly energy-intensive, producing large amounts of heat as a by-product, which has historically been vented away into the atmosphere. This heat, that would otherwise be wasted during production, is being redistributed through the local grid and recycled into district heating to heat circa 2,500 apartments in Gustavsberg.

Seeking methods to improve the efficiency of its processes, AstaReal turned to Vattenfall for support in developing a sustainable solution, who designed and installed a specially adapted, on-site heat facility, integrating pumps to recover fifteen million kilowatt hours of wasted heat per year. 

Powering sustainable solutions

The project, which is the first of its kind in Sweden, now makes up 20% of Gustavsberg district heating. Fredrika Liffen Rappe, Quality Assurance and Sustainability manager at AstaReal, said:

“We have received certified climate neutral and EPD-certified power from Vattenfall for many years, and our sustainability collaboration has now led to us having a new facility for heat recovery. Our extended partnership fully aligns with our ambition to grow the algae as sustainably as possible and to be a positive force in society with a circular business.”

Electrical infrastructure specialist, Vattenfall Network Solutions, will continue to be responsible for AstraReal’s on-site facilities, operations and administration in the future. Via its Power as a Service (PaaS) model, the energy company will own and manage all high-voltage electrical installations on behalf of AstraReal, including its transformers and switchgears.

AstaReal’s Fredrika Liffen Rappe added:

“Our cultivation process is highly energy-intensive because algae need powerful and uninterrupted light supply to survive and grow. This is why it is crucial that we have a stable supply of power – and that the power reserve kicks in, in case of a power outage. Vattenfall’s PaaS guarantees us the energy needed for production.”

AstaReal production of algae
AstaReal’s production of Astaxanthin

Fossil-free living

Vattenfall Network Solutions have been developing and operating electrical networks for more than 100 years. Through its PaaS model, the division shoulders full financial and functional responsibility for their customers electrical facilities, and manages any compliance, regulatory and environmental issues.

Torbjörn Johansson, Head of Vattenfall Network Solutions in Sweden, commented:

“We’re proud to be able to support AstaReal’s ambition to find more fossil-free solutions, while at the same time they’re able to transfer all responsibility for the plant’s heat recovery through us owning, managing and ensuring its function.

“We look forward to expanding our partnership with AstaReal, who will be a pioneer in this new technical solution.”


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