#103 - The Rjukan Model

This week while searching news in the Blue Economy, I found a very cool case study linking to my university MSc dissertation (industrial symbiosis models).

Green Mountain (data center) × Hima Seafood (land-based aquaculture)

Distance: 800 meters

Industrial symbiosis: where the waste of one industry becomes the resource of another, is well-documented in academic literature. What's less common is seeing it operationalised at commercial scale, with embedded infrastructure and aligned incentives from the cradle.

A recent collaboration in Rjukan, Norway, offers a great example of how it should be done. Green Mountain, a data center operator, and Hima Seafood, a land-based trout producer, have built a closed-loop heat exchange system that turns thermal waste into productive energy. The system has been operational since Hima's facility came online in 2025, but the infrastructure planning began years earlier.

This isn't a pilot, It's production infrastructure. It has direct implications for how we think about site selection in capital-intensive blue economy sectors like land-based aquaculture.

Enjoy!

The Setup

Two industrial facilities in Rjukan, Norway, have operationalised a closed-loop heat exchange between a data center and a land-based trout farm.

• Heat source: Green Mountain data center (operational since 2014)

• Heat sink: Hima Seafood RAS facility (8,000 tonnes/year target capacity, 55 FTEs)

• Infrastructure: Underground pipelines installed during construction phase

• System: Closed-loop — warm water flows from data center to aquaculture facility; chilled water returns to support cooling

The companies are located just 800 meters apart in the same industrial zone. That proximity isn't incidental, it's the entire basis for the collaboration.

Why It Works

Proximity matters: 800 meters is short enough for heat transfer efficiency and cost-effective pipeline infrastructure, but long enough to avoid operational interference between two very different industries.

Timing was everything: Infrastructure was embedded early. Pipelines were laid before Hima's facility became operational. This wasn't a retrofit or an opportunistic add-on, it was designed into the system architecture from the start. That's the difference between industrial symbiosis as a planning principle and industrial symbiosis as a lucky adjacency.

Mutual dependency creates resilience:

• Data centers generate significant thermal waste and require continuous cooling

• RAS facilities need stable water temperatures and consume substantial energy for heating

• Both industries face pressure to improve energy efficiency and reduce carbon intensity

The byproduct of one becomes the input of the other. The result is a system that's more efficient and more resilient than either facility operating in isolation.

Operational Impact

For Hima Seafood:

• Reduced electricity consumption for water heating (exact figures not disclosed, but heating is a major energy line item in RAS)

• Improved temperature stability in production tanks, which supports fish health and growth consistency

• Strengthened operational resilience through diversified energy sources

For Green Mountain:

• Enhanced cooling efficiency via returned chilled water, reducing reliance on external cooling systems

• Productive use of otherwise wasted thermal energy, improving overall energy utilization metrics

• Strengthened sustainability credentials in a sector under increasing scrutiny for energy consumption

For Rjukan:

• Both firms are part of Sirkulære Rjukan, a regional circular economy initiative connecting multiple businesses through shared resources

• Demonstrates how existing industrial zones can be reimagined around resource flows and circular design principles, rather than just tenant mix or proximity to transport links

This is infrastructure that generates value for both parties while reducing aggregate energy demand at the industrial zone level.

The Industrial Symbiosis Lens

This is a textbook case of industrial symbiosis: two unrelated sectors creating value through co-location and waste stream integration. But what makes it notable is the execution.

What makes it replicable:

• No novel technology — heat exchangers, water pipes, and closed-loop systems are standard industrial infrastructure

• Embedded during construction — planned and built as part of the facility design, not negotiated retrospectively

• Aligned incentives — both parties reduce operating costs, improve sustainability metrics, and strengthen operational resilience without creating dependencies that introduce new risks

What makes it rare:

• It actually got built. Most symbiotic opportunities remain theoretical because coordination costs are high, planning timelines don't align, and infrastructure investment requires upfront commitment before both parties are operational.

Rjukan succeeded because the infrastructure was designed in from the beginning, not bolted on later. That required foresight, coordination, and a willingness to invest in shared systems before the operational benefits were fully visible.

Implications for Blue Economy Site Selection

If you're building land-based aquaculture at scale, co-location with thermal waste sources should be a site selection criterion, not an afterthought or a nice-to-have.

The energy economics of RAS are well understood: heating, cooling, pumping, and water treatment account for the majority of operating costs. Access to low-cost, low-carbon thermal energy can materially improve both the environmental and financial performance of a facility.

Potential symbiotic pairings worth exploring:

• RAS + data centers (as demonstrated in Rjukan)

• RAS + industrial process heat from manufacturing, refineries, or chemical plants

• RAS + district heating networks for urban integration

• RAS + wastewater treatment facilities (nutrient recovery and thermal energy)

• Algae/seaweed production + power generation or heavy industry (CO₂ capture and thermal inputs)

The Rjukan model demonstrates that circular design beats circular retrofitting. The earlier these relationships are identified and embedded into infrastructure planning, the more likely they are to succeed.

Conclusion

Hima Seafood's CEO, Annar Bøhn, noted: "This can become a model for how we build going forward."

As land-based food production scales, as energy costs remain structurally high, and as decarbonisation mandates tighten, site selection will increasingly favour locations where waste streams align and resource flows can be integrated. Industrial zones designed around circular principles will outperform those organised purely around transport access or labour availability.

The question isn't whether industrial symbiosis works: Rjukan proves it does, at commercial scale, with standard technology and aligned incentives. The question is whether planning frameworks, zoning policies, infrastructure financing models, and regional development strategies will adapt to prioritise and support it.

Industrial symbiosis shouldn't require exceptional foresight or unusual cooperation. It should be the default design principle for new industrial development, especially in energy-intensive sectors like aquaculture, data infrastructure, and advanced manufacturing.

Rjukan shows what's possible when waste (heat) stops being waste and starts being infrastructure.

Food for thought!

Read the full press release: Green Mountain announcement

OTI - H