NORWAY: An 800 million NOK expansion of operations at Nordlaks Smolt AS has resulted in one of the largest recirculating aquaculture systems in Norway. Even brief downtime can have serious consequences for the health of its young salmon, so reliable operation is key.
Since this is an energy-intensive industry, Nordlaks has prioritized its own sustainable electricity supply from a local hydroelectric power plant, even recovering excess heat to convert to energy. This means Nordlaks’ main focus is not on energy efficiency, as might be expected. Instead, reliability is the most critical aspect of the operations. For this reason, three emergency backup generators are installed, ready to assume power production should there be an interruption in supply from the public grid.
Problem-free harmonic mitigation
The installation is fed from the distribution network through three dedicated transformers. Calculations made during the planning phase showed that harmonic levels would be too high, particularly when running on the backup generators. Therefore, one active harmonic filter was installed for each of the three feeders. These active filters have ensured voltage harmonics are kept well within acceptable limits at all times.
“For me, as head of electro, no news means good news. The filters are online and doing their job and the voltage harmonic level is kept below 5% THDv at all times. So far we have not encountered any problems with harmonics. Danfoss and Comsys provide a simple, straightforward, well-proven and economic solution. At the same time, they follow up on their customers’ needs with high standards”
- Bram De Roy, Head of Electro Department at Nordlaks Smolt AS
VLT®AQUA Drive delivers superior load control
The Nordlaks facility in Innhavet is a complex plant with a large number of loads consisting mainly of pumps, fans and compressors. During the selection process for variable speed control, Nordlaks chose VLT® 6-pulse drives since they offered superior performance in terms of both reliability and high-frequency noise, compared to the next best alternative. Over two years, a total of 200 new VLT® AQUA Drive FC 202 units were installed to ensure variable speed load control and secure energy savings. The FC 202 drives are rated from 1.5 kW to 55 kW, primarily supporting the pumping operations.
In-depth support makes all the difference
Since reliability was the main selection criteria, trust and proven performance played a significant part in specifying the project. During the planning phase, Svein Robert Haldar of Danfoss Drives and Henrik Sjökvist of Comsys were constantly in touch with Bram De Roy of Nordlaks, to ensure he could make well-informed decisions, and to ensure successful commisioning of the plant. Despite the distance to Innhavet in remote northern Norway, the team met on multiple occasions, to ensure optimal solutions and successful start-up.
“We found it extremely rewarding to work with Danfoss and Nordlaks on this project. Danfoss drives are extremely versatile with broad compatibility with all typical technologies, regardless of make. So together we were able to use our active filters to achieve the most superior technical performance optimization possible, for this application. What’s more, we know Danfoss is as willing as we are to invest time with the customer in explaining the technology and providing on-site training. For this project, Danfoss and Comsys worked together to deliver truly in-depth knowledge sharing to Nordlaks. Now that is a solid team!”
explains Henrik Sjökvist of Comsys.