Siemens recently unveiled its latest microgrid at Wildpoldsried in Germany’s Allgäu region and its effectiveness may see uptake by municipalities keen to demonstrate greater resiliency and commercial opportunity.
Markus Reischböck, (right) product manager for Siemens ( FWB: SIE ) Microgrid spoke to Decentralized Energy about the potential benefits of the latest incarnation of the company’s microgrid technology.
The project, part of the IREN2 research programme, aimed to technically and economically optimise a smart energy system with distributed power generation. The company partnered with universities and network specialists in Germany to develop a microgrid aimed at incorporating distributed renewable energy more effectively.
The main beneficiary in this successful case, incorporating solar photovoltaic (solar PV) and small scale wind energy with intelligent control, was Allgäuer Überlandwerke, and it’s not the first time this municipality has participated in new power technology research.
“Most of our past projects were lab-based with no customers involved, no utilities involved no real utility grid involved,” says Reischböck. “We have been collaborating with this local utility for the last seven years. For this latest research project, we got community acceptance there to operate a portion of the village as a microgrid. It’s not a lab, it’s a real network with real customers. It’s a real microgrid with no simulation in a real community grid.”
At Wildpoldsried, the experts initiated a deliberate power failure, putting out the lights in the affected part of the low-voltage grid. They then restored the power supply, but as a local isolated network. Now that Siemens has proven its latest microgrid concept, it’s set to be rolled out in other German regions and beyond.
“We are in discussion with several cities – mainly smaller communities so far, mostly with around 10,000 inhabitants who are interested in such solutions mainly for two reasons – one they would like to promote themselves as the go to utility in their region through this kind of different customer value proposition they are offering.”
While presently the German renewable market offers a great deal of subsidies, that chapter of energy policy is to draw to a close. So the inclusion of these types of microgrids offer the chance for municipalities to stand out for potential regional customers, such as PV owners.
“They could market their power to the German electricity market as a kind of aggregator. If they have commercial contact with solar PV, biomass producers and wind owners they can additionally provide to the community the possibility of microgrids. They bring the capacity to the market on one side and on the other side provide a kind of insurance to be able to supply power when the German or EU grid is down.”
“It’s an additional value proposition and is mainly for the smaller utilities as German regulation for them is not valid – so they can be producers, consumers and network operators.”
“The inhabitants of this village are selling energy to the market, as they produce five or seven times more energy than they can consume- that is their business case.”
Despite the advances made, microgrid island operations serve as more of an insurance or back-up in Germany, unlike some developing nations, where, in the absence of a sophisticated grid, the microgrid can be the main event.
In terms of the returns for those who provide their power to the grid in Germany, that’s based on the needs of the grid and the available assets of the grid at the time.
“So in such a village you have solar PV but the sun doesn’t shine in the night so the question is if you want to have microgrid running during the night. You take a battery and then you have to add another business case for the battery –maybe pooling it and using it for the primary reserve market, secondary or tertiary reserve market.”
“A more valid or cheaper option is local CHP because they produce heat and electricity. Of course, you would have to adapt these assets a little bit to make them work in an island.”
For all these primary assets you need a business case where they can make 99 per cent of their money through market participation or selling energy or ancillary services and then you have an additional investment for running it in island mode. This investment is hard to judge. It’s mostly control and automation of the assets so I would say it’s not a seven-digit number.”
At Wildpoldsried, solar PV, biomass and battery storage are all in action, with the additional safety net of seldom-to-be-used diesel generation.
At the heart of managing that selection is the microgrid controller. While it doesn’t require the bulk of the financing for such projects, it’s a key component for proper use of assets and particularly in blackout conditions.
“We are using a typical microgrid controller based on a Siemens automation platform which we also sell to other projects around the world. This project here is a main test site where we test the implications for innovations in microgrids.”
“Automation is normally 10 per cent of the investment. One portion of that is the controller and the other is the communication. You cannot use standard communications such as mobile as in blackout situation normally your phone doesn’t work anymore as the tower will only have a long-time reserve of 15 to 20 minutes. So, when you think about a microgrid you also have to think about a communication concept.”
The German government does recognise the value of microgrid technology but it remains marginal to policymaker thinking for now.
“It’s perceived mainly as ancillary services as all large power plants are being shut step by step, with nuclear and coal to go. However, on the research site its getting more acknowledgement by some politicians and officials, although not in the mainstream, of its potential to increase the resiliency of the German grid if we have no large power plants anymore.”
“At the moment, in the case of a large blackout, we would need to restore the grid from France or elsewhere. So, while this activity is still more at the research level, they are pushing projects dealing with how microgrid can help in case of blackout, even if it’s not yet part of the regulations.”