The energy scene is shifting. The range of distributed power generation sources such as solar cells, wind turbines and cogenera-tion plants is growing constantly. And it is happening in tandem with the dynamics of a digitalization process that has already rocked some industries to the core. The combination of these two phenomena has led to the emergence of small-scale power networks or ‘microgrids’ – soon to be available from MTU as package solutions complete with battery and control system.
Photovoltaic systems, wind turbines, hydro-electric plants, diesel gensets and combined heat and power (CHP) modules – whether operating separately or in concert – can all be included in a microgrid. They are not new. In 2017, more than 500 gigawatts of installed wind power capacity and around 400 gigawatts of installed photovoltaic power capacity were already available. By comparison, global nuclear power capacity was just 391 gigawatts. So far, however, the major challenge has always been how to store that power and then release it just when it is needed. CHP plants and diesel-powered gensets are always available but compared with regenerative energy sources, they are not always economical
Microgrids now provide a solution by combining both types of power generation and including batteries and a control system to integrate all the elements in a smart system. “Microgrids combine cost-efficient and ecologically friendly regenerative energy sources with the reliability of our gensets to create a concept for the future of power generation,” declared Alexander Patt who heads MTU’s microgrid development team.
Battery containers from MTU
MTU is currently developing a battery container that incorporates 154 modules and 3,388 lithium-ion cells. Together, these elements can store around 1,000 kWh of electrical energy – that is about 14 times as much as a Tesla Model X. MTU’s battery container also boasts around 2,000 kW of electrical power and a capacity of 1,095 ampere-hours. A transformer adapts the output voltage of the MTU battery container to match the connected power grid. “The battery container will have a modular design to maximize flexibility for adaptation to our customers’ power needs,” said Patt.
Control at the core
Whatever else is involved, the critical component in a microgrid is the control system. “It has to be predictive, smart and self-teaching and it has to deliver exactly the right energy mix for the customer’s needs,” said Armin Fürderer, Team Leader for Electrical Systems, PowerGen at MTU. To enable the control system to decide which power sources to use, the customer has to specify the key parameters: Is his priority cheap power generation or is ‘green’ power from regenerative sources more important? Or is availability the key factor? Based on these parameters, the control system calculates which energy sources to use and when and whether to feed consumers or charge the batteries. This is where artificial intelligence also comes into play. “A modern microgrid control concept must be smart enough to accurately predict which energy sources will be needed to deliver the perfect energy mix. We are not going to achieve that with classical software architecture. We need to think outside the box here,” said Fürderer. The first stages on the journey to an MTU Microgrid will soon take visible shape. The MTU battery container constructed at the company’s Ruhstorf location will provide the first element for a planned new MicroGrid Validation Center at the Friedrichshafen facility where it will store power from the photovoltaic installation for supply to the MTU production section when needed. Several CHP modules from MTU Onsite Energy are available to take over when the battery container has been discharged.
The content of the stories reflects the status as of the respective date of publication. They are not updated. Further developments are therefore not taken into account.