Picture: LEW / Timian Hopf

Photovoltaics and hydropower cooperate for emergency power

LINDA 2.0 investigates the possibilities of using green electricity, for example from solar energy, in the emergency power supply in the event of a blackout. Another aim of the overall project is to make renewable energy systems, such as photovoltaics or hydropower, usable for emergency power supply. The technologies developed in the first LINDA project are to function largely autonomously by means of appropriate software.

LINDA 2.0 is divided into two sub-projects that are being implemented in parallel and in several field tests:

1. Development of a new emergency power unit

It is intended to supply a local grid with electricity in the event of a power blackout in such a way that existing renewable energy power generation plants continue to feed electricity into the local grid. Up to now, emergency power generators have been operated in such a way that such plants shut down temporarily.

With the new approach, the plants could help meet electricity demand in the event of a power outage. In the project, the diesel genset is also to be equipped with a battery that can store surplus electricity and release it when needed. This means that less diesel has to be used, or a hybrid unit can be operated for longer with the same diesel supply.

2. Automated emergency power supply in stand-alone operation

In the second project strand, the approaches to emergency power supply developed in the first LINDA project will be continued. In the field tests planned for LINDA 2.0, ODK’s Leipheim hydropower plant will supply the pumps of the Niederstotzingen pumping station with electricity in isolated grid operation.

This emergency power operation should run as automatically as possible and without additional personnel. To this end, the project partners are developing the necessary programs and routines, which will then be tested in several field trials.

LINDA taps renewables for emergency power supply

Up to now, regenerative energies have not been available for the emergency power supply. The systems switch off in the event of a power failure or when an emergency generator is used, as they only feed in energy within certain frequency bands in the power grid.

Up to now, emergency power generators have deliberately been operated outside these frequency bands. The LINDA 2.0 project(Local island grid supply and accelerated grid reconstruction with decentralised generation plants in the event of large-scale power failures) is investigating how these plants can nevertheless be used to cover the power demand in the event of a power failure.

The Federal Ministry of Economics and Technology is funding the research project as part of the Energy Systems Research programme. LINDA 2.0 runs from 2021 to early 2024 and includes several field tests in the subprojects. In the first sub-project, the project partners want to gather experience in the operation of diesel gensets with battery storage systems, which are fed by PV systems in the local grid, for example. With such emergency power operation, less diesel would be consumed, and the CO2 balance would improve accordingly. Also, such a hybrid unit could possibly supply more households than a conventional one.
In the second subproject, the requirements for the supplying executive power plant in the automated emergency power supply are to be worked out. This would allow the emergency power supply to be started remotely without the need for staff to be on site.

Successful islanding trials in the first LINDA project

LINDA 2.0 uses findings from the previous project, which ran from 2015 to 2018. In several field tests, a stable island grid operation with renewable energies was successfully established. In the field tests, the stand-alone grid comprised individual large consumers, but there were also successful field tests covering several localities with more than 1,000 households as well as a large number of generation plants. The LINDA project was awarded the ISGAN Award (International Smart Grid Action Network) and the Bavarian Energy Prize.

In addition to the Augsburg University of Applied Sciences, the Technical University of Munich, LEW Verteilnetz, LEW Wasserkraft and Obere Donau Kraftwerke AG, the following project partners are involved in the LINDA 2.0 project:

  • State Water Supply Stuttgart
  • KIMA Automatisierung, company for electronic control engineering and construction mbH
  • AVS Aggregate Construction GmbH
  • University Hospital Leipzig AöR
  • MTU Onside Energy GmbH
  • Power electronics cluster

Information on the LINDA project is available at: www.lew.de/ueber-lew/zukunftsprojekte/linda-20.