Anyone who has taken a walk along the Kiel Fjord (located on the Baltic sea coast in North Germany in the state of Schleswig-Holstein) in the past will remember the large chimney and the cube-like buildings on the eastern shore. The old joint power plant was fuelled by imported hard coal and supplied 60,000 households with district heating in addition to its electricity production. This has been a thing of the past since 2019, and the coastal power plant, a modern, modular gas-engine CHP plant, was built right next to this truly non-environmentally friendly fossil fuel on behalf of Stadtwerke Kiel.
Speed is flexibility
Beneath the four characteristic chimneys are 20 gas engines, which are grouped into four blocks. They were designed from the outset to also run on hydrogen. The new power plant is now much more flexible in its electricity generation than the old coal-fired power plant, as the engines need less than five minutes to start up from standstill to their rated output of 191 megawatts. At the same time, they can generate a heat output of 200 megawatts during operation.
Balancing the grids
The electrode storage tank integrated into the power plant is another highlight of the flexible energy distribution system. In the 60 metre high storage tank, 30,000 litres of water can store up to 1,500 megawatt hours of energy in the form of heat and thus, for example, absorb the excess supply from wind turbines during strong winds. The heat generated can then be passed on to the more than 70,000 district heating customers with a time delay, and the fluctuating ratio of supply and demand is optimally utilised and buffered.
Not only effective, but also clean
The principle of combined heat and power generation in the Kiel coastal power plant is the most modern way of generating energy and heat currently known. The power plant has an efficient primary energy utilisation of 90%, and by dispensing with hard coal and using natural gas and, in future, hydrogen, over 70% less carbon dioxide is emitted than at the old joint power plant. In figures, that is 1,000,000 tonnes less per year. To ensure that the Schleswig-Holstein state capital of Kiel is supplied with electricity and heat, a well-coordinated team of experts works on and with the engines on a daily basis, using professional tools.
The team for safety
A permanent team of 10 heating technicians, made up of electrical engineers and industrial mechanics, takes care of the maintenance and servicing of the electrode tank and the heat accumulator as well as the 20 motors. Even though the power plant is still virtually brand new, all relevant assemblies still have to be checked regularly. An inspection of the plant takes place every 72 hours, as agreed with the responsible supervisory authority. And every four weeks, the engineers also check the safety devices of the electrode vessel. The heat storage tank alone has 36 temperature measurements for the individual layers. Should there be any deviations or a defect, an alarm is automatically triggered in the control centre. The team moves out, searches for the fault, checks the measurement or replaces defective parts.
Large calibre pliers
That's why in the part of the workshop we were allowed to visit, there are mainly very bulky pliers and bolt cutters next to huge ring spanners. Changing seals, securing stud bolts and cutting cables - KNIPEX can be found in every corner here. After all, the team has to rely on its tools to guarantee the power supply to the state capital. But smaller pliers are also well stocked alongside other branded tools in the technical service area of the power station. They are prepared for anything. Just like professionals.
The fascination of large machines
The large gas engines and the people who control and operate them exude a very special fascination. This will probably be the case with anything that can produce such quantities of energy. With the coastal power plant, the North German state capital of Kiel is well equipped for the future, and with this team and these tools, not much can go wrong.
