“How can we operate wind power systems more efficiently and develop offshore farms in new directions? We want to make renewable energy less costly, produce it on a sustainable basis and foster harmony of man and the environment. This will benefit us and in particular our customers.”
Dr Claus Linnemann is our specialist for new technologies relating to the use of wind and solar power.
In the future, the energy that powers our world will be generated primarily from renewable energy sources like wind, water and the sun. This development permanently requires new technologies to safeguard our supplies going forward.
innogy is already one of the world’s largest operators of offshore wind farms. We intend to keep growing in this sector in the future. We are currently building new wind farms that have a combined capacity of several hundred megawatts primarily in the North Sea.
And we round off our commitment to environmentally friendly power supplies with projects revolving around other types of renewable energy sources such as solar power, hydropower and biogas.
Wind power. Onshore wind turbines still generate most of our wind power today. However, an increasing number of wind farms is being built in the open sea. Acceptance of these offshore wind farms among the population is also growing. Furthermore, offshore wind farms generate more electricity than the ones onshore, since the wind is much stronger and constant in the high seas.
innogy has been operating offshore wind turbines since 2004. Together with partners we have erected wind farms off the coasts of Germany, Belgium and the UK. In fact, we are building the Triton Knoll windfarm off the British coast together with partners. We were able to win the award for this 860 megawatts offshore wind project in an auction in the UK.
We have also been successful in the German auction for the Kaskasi offshore windfarm off the German coast, which is another milestone for the value-driven development of renewable energies. The site northwest of Helgoland is characterised by good wind conditions and moderate water depths of between 18 and 25 meters. The windfarm is currently expected to go into operation in 2022. Like Triton Knoll, Kaskasi also strengthens the competitiveness of innogy in demanding markets.
We intend to reduce the costs for the erection of offshore windfarms specifically in deeper waters even more. This is why we are exploring innovative methods when it comes to the design and installation of system foundations. As part of the GOAL project, we have been investigating together with partners since 2014 whether the present special mortar can be replaced by less costly conventional cement for the construction of foundations. A proven type of foundation is the so-called jacket, a steel structure on four legs. The jacket legs are placed into foundation piles which were rammed into the seabed before. The annular gaps around the legs are closed with special mortar afterwards.
Building these foundations at lower costs is key to success when it comes to increasing water depths and larger wind turbines of the next generation. This is why we are testing conventional cement mixed with seawater, a process which has already been applied successfully in the offshore oil and gas industries for quite some time. However, the material of wind power systems is exposed to totally different stresses. First results of the data evaluation are very promising.
“Our sophisticated methods of analysing the data from our wind turbines enable us to detect any damage very early on, long before it causes downtimes.”
Dr Kirsten Theobald’s aim is to make the use of wind power as efficient as possible
Plant security. Inspecting our wind energy systems involves risks for the technicians. Sometimes they are only secured by ropes when they are suspended from heights of more than 100 meters. Not only the examination of the rotor blades, but also the inspections inside some of the systems are a dizzying challenge.
Take, for example, the concrete towers at our Bedburg windfarm. The lower 80 meters consists of individual annular segments placed upon each other and tensioned with steel cables. These steel cables have to be checked regularly for potential damage.
This is where a little helper comes into play, which we are testing in the windfarm: the ELIOS drone of the Swiss manufacturer Flyability developed specifically for indoor environments. It comes with light and a camera on board, and is placed in a spherical cage. This provides protection in case it hits any structures when flying around near system components.
ELIOS produces high-resolution images and has been designed specifically for inspections in places that are hardly accessible to people. The pictures taken during the first test in cooperation with the company Spectair from Meerbusch are now being evaluated in depth. Moreover, we are determining other potential requirements for the technology. For instance, a drone with infrared camera could be attractive to inspect the power busbars inside the systems.
Photovoltaics. Electricity generated by photovoltaic systems can be competitive today, even when produced in our latitudes without subsidies. Innovations of innogy’s subsidiary Belectric also contribute to this favourable development. With its focus on commercial-scale photovoltaic power plants, the company has already erected installations with a total peak capacity of two gigawatts.
Belectric has developed a solution requiring much less material and expenses as an alternative to the usual, fairly solid substructures: using the so-called PEG system, installations in east-west orientation are erected only on a large number of precisely rammed steel rods – at much lower cost.
Moreover, Belectric develops solutions contributing to grid stability as the generation from renewable energy keeps growing. This is achieved by integrating battery storage facilities and their optimum design and management. These so-called hybrid systems help maintaining the frequency in the power grid and can also provide energy irrespective of current solar irradiation up to a certain degree.
Such hybrid systems can also be combined with other generation technologies. What is more, they can be used to ensure supply security in world regions far away from stable grids without having to rely on large-scale, conventional power generation units.
Biogas. innogy operates its own biogas installations in order to explore ways of generating as much energy as possible from renewable resources. We have commissioned a modern biogas plant in Paffendorf in the City of Bergheim (in the state of North Rhine-Westphalia) that generates energy in an environmentally friendly manner from renewable resources. We use a diverse mix of raw materials drawn from products used in the region’s farms, for example, whole plant, grass and maize silage as well as beets and alfalfa. They also test the use of new energy crops such as cup plants and wild flowers. The raw biogas that is generated is then processed to natural gas quality and fed into the grids in the form of bio-methane. This bio-methane can be used to supply heat to around 3,300 households.
Biogas plants are more profitable the more reliably they operate. This is why we are carrying out the Visko project at Paffendorf to investigate ways of preventing “blockages” at biogas plants. Such blockages can arise when the substrate – that is, the raw material that is used to power the plant – becomes too viscous. The bacteria cannot do their job properly if the substrate is too viscous, which in turn causes biogas production to come to a halt. We now deploy a measuring system at Paffendorf to continuously monitor the substrate’s viscosity and detect when it becomes too high. We implement the appropriate countermeasures to prevent downtimes at the plant.
In a biogas plant currently being erected at Neurath we are testing a technology right now which is designed to benefit the reliable operation of wind power systems in the future: we are collecting a lot of data of the system by means of sensors on an ongoing basis and provide them for evaluation via a link to the Cloud. Since the biogas plant is not very complex, only several hundred different measured values arise, which is perfect for a development project. In wind power systems, however, some 3,000 values are collected. Such a system is designed to help identify damage early on or even prevent it entirely in the future through the automated analysis of data on pressure, temperature, vibrations and a lot more.
Hydroelectric power. The main benefit of hydroelectric power is that it can be used to generate electricity largely irrespective of time of day or weather conditions. innogy operates run-of-river and pumped-storage power plants with a combined capacity of some 500 megawatts. These plants harness the energy of flowing rivers and work around the clock very reliably. We have over 77 turbines at almost 30 sites in Germany alone, for example, at the Moselle, Ruhr and Saar rivers. We operate 21 of such power plants in the UK. We also operate hydroelectric power plants in France, Spain, Portugal and Switzerland.
Hydroelectric power plants can be an obstacle for fish. They may be caught in the turbines especially when migrating downstream. Together with scientists of RWTH Aachen University we are therefore investigating how they can migrate without any risk.
Hydroelectric power plants are always equipped with intake screens. Their grating structures protect turbines from flotsam. It would be technically very complicated and expensive to reduce the spacing of the rods to such an extent that the fish would not be able to pass through. In the OVeR project we are therefore investigating if the intake screens can be designed in such a way that they guide the fish, which detect the barriers by means of a remote tactile sense, towards specific downstream ladder installations. In a laboratory-scale water channel of RWTH Aachen University we are testing various screen types with different fish species. This is intended to safely guide the animals past the screen and the dangerous area through a bypass.