Green storage battery

Andreas Hernandez — The new hydropower station in Lysebotn generates 15 percent more energy than the old one. How is this done?

Bjørn Honningsvåg — By producing more electricity with the same volume of water. The water flows from the reservoir, which is very high up above sea level, down into the valley through a new tunnel we have built that is almost eight kilometers long. The reservoir itself remains unchanged, and the surroundings were left largely intact. Almost all the work needed for the new structure took place inside the mountain.

What exactly do the new ANDRITZ units provide?

B. H. — When both high-head Francis turbines are running at full power, they provide a total of 370 mega watts. The old plant could only provide 210 megawatts. Lysebotn‘s annual capacity has increased to 1.5 terawatt hours. As the existing reservoir is utilized for the new units, there was no need to apply for a new environmental license for this, which would have been quite expensive and complex.

Why was this new construction needed in the first place? What is the significance of the power station for Lyse?

B. H. — One reason is the higher capacity, as I already mentioned. But that’s not the whole story. We will also become more efficient and more flexible. Well over 200 million euros have gone into the entire new construction, and we consider this a wise, long-term investment that will make us more agile and more competitive overall. An important driver is the EU ’s environment policy and strategy applying until 2050: The member states are intensifying the use of renewable energy sources, and they will possibly consume twice as much electricity in the future as they do today. We want to have a share in this. The higher generating efficiency is also giving us the opportunity to apply for Green Energy Certificates as an additional source of income for the power plant.

In what respect?

B. H. — One of the big advantages of hydropower is that production can be started and stopped flexibly – unlike thermal power stations, where starting and regulating are expensive and can also take several hours. Lysebotn II is like a huge, green storage battery that will supply Germany and the UK, as needed, with additional power as soon as sub-sea cables have been laid to increase the interconnection capacity between Norway and continental Europe/the UK . The respective construction projects are already underway.

What is the role of ANDRITZ in this context as Lyse's partner?

B. H. — ANDRITZ presented a very competitive proposal. In addition, we wanted a partner with a great deal of know-how and experience with high-head Francis turbines and found the match needed to meet our specific requirements in ANDRITZ. The water from the reservoir rushes into the plant from a height of 665 meters at a rate of 60,000 liters per second. These are very demanding conditions that exert extreme stress on the equipment. We need very robust, compact, and efficient turbines that are able to handle the tremendous forces reliably – turbines that can be started and stopped frequently as needed without any difficulty and are tailored precisely to our needs.

What does that mean exactly?

B. H. — The so-called condenser mode that can be used to operate the turbines is important in our view. Without delving too deep into the technical details, it means that the unit is operated in air (the water is drained from the runner and the generator is used as motor). In this operating mode, the unit can provide important auxiliary services to stabilize the frequency of the grid. If more and more fluctuating energy sources like wind and photovoltaic are feeding the grid, this could become a valuable service that we would like to sell to the network operator.

The new power station has been operating now for several months. What is your interim conclusion?

B. H. — Lysebotn II is running to our full satisfaction. Of course, we are constantly involved in fine tuning, but that’s normal. When we sealed the project in the contract with ANDRITZ in November 2013, we agreed on July 20, 2018 as the commissioning date. Thankfully, we also succeeded in meeting exactly this date although the logistical demands were challenging: All components had to be shipped through the fjord, the schedule was tight, and there was not a lot of space inside the plant for storage and maneuvering. Nevertheless, everything was completed on time, with only one moderately serious accident, and that is very important in our view. Occupational health and safety are our highest priority.

What is the next step? What plans does Lyse have for the future?

B. H. — We will be installing the Metris DiOMera system from ANDRITZ in spring 2019. This is a digitally supported tool that we can use for predictive optimization of maintenance work. DiOMera  constantly monitors a large number of sensor data that we receive in real time from power plant operations. We can use this to forecast the residual life of components and draw up precise maintenance schedules to keep downtimes as short as possible. Digitalization in this form has a clearly positive effect that we also want to use in other power plants in future. More flexibility and efficiency at lower cost: This is one of the major goals throughout the Lyse Group. ANDRITZ is helping us to achieve it.