Power outages are a rare phenomenon in Germany but this could all soon change: Extreme weather conditions – such as those that recently caused blackouts in North America – are also being seen more and more often here and are pushing our comparatively robust grid to its limits. Our infrastructure is also under threat from cyber attacks and physical attacks. Several homes in Munich were recently left without electricity for two days following an arson attack. Although the continental networking of energy supply systems can help balance out differences in supply and demand, it can also lead to a snowball effect – for example, a small issue in Croatia caused a power cut across large parts of Southern Europe as recently as January this year. And last but not least, large power plants are being replaced by numerous small photovoltaic and wind power plants. This decentralised and increasingly smart grid, however, bears stability risks.
How can we develop a resilient smart grid against this background? Research groups at TU Darmstadt are examining precisely this question. A team headed by Professor Max Mühlhäuser in the Department of Computer Sciences is, for example, developing algorithms that split the smart grid into viable islands in the event of a power outage. These islands would then automatically reunite again as soon as possible.
Rolf Egert, doctoral candidate and head of the group “Smart Protection in Infrastructures and Networks” (SPIN) wants to integrate consumers into the process to a much greater extent: “We need their cooperation in order to develop a robust electricity grid – and not just as investors in renewable energy”. Egert is focussing above all on private households. “They are responsible for around one quarter of the electricity consumed in Germany – and the proportion of them who are also electricity producers is growing at the same time”, he says.
We need their cooperation in order to develop a robust electricity grid.
Egert, Mühlhäuser and other researchers have published a vision paper that was preceded by a scientific survey of private citizens. The aim was to gain an initial impression of how aware customers are about existing problems and how willing they are to play their part. If there is a power cut on the national grid in the future, the researchers anticipate that, for example, solar power plants, wind power plants and batteries will still be able to supply some electricity decentrally but demand will typically exceed supply. In the event of an extreme shortage in supply, the local operator is currently forced to intervene, leaving some streets with a full supply of electricity while shutting off the supply to others – and potentially also shutting down vital equipment and local energy producers.
In a smart grid, the households who draw electricity should be able to decide which devices remain switched on and which are turned off. This creates a complex problem: How can a fluctuating supply satisfy the various needs of different people?
Idea puts many people off
In general, consumers could allow their devices to be switched on and off remotely. If there were a supply shortage, the grid operators would switch off, for example, any heat pumps or water boilers. This idea horrifies many people because of the fear that their energy provider would, for instance, suddenly switch off the warm water while they are taking a shower. Therefore, it would be much more sensible for consumers to actively get involved with the smart grid.
The team headed by Egert is developing a prototypical framework that can intelligently network local resources. This requires them to overcome numerous challenges – many things that work successfully in industrial companies cannot simply be transferred to private households. It is also important to take the preferences of each household into account. “As a private citizen, I can then define which devices can be switched off and at what times”, says Egert. “For example, I can permit my air conditioning system to be switched off on workdays for up to five hours when I am not at home”. Machine learning can be used to help understand the habits of electricity customers and then make appropriate recommendations. But this also requires people to engage with the subject matter and make decisions.
In addition, it is important to prevent antisocial behaviour. Some individuals could fool the system by pretending that they have high priority needs, thus ensuring that their local neighbourhood is hit even harder. How can people be motivated to make a positive contribution instead? “It seems reasonable to believe that people would respond to a reduced electricity bill or financial incentives”, says Egert, who is working together with experts from the field of psychology.
Extrinsic motivation not sufficient
“However, this type of extrinsic motivation usually only works in the short term”. Even ideas such as simply visualising consumption data, as is possible on some smart meters, or green electricity suppliers providing the customer with information on how much CO2 has been saved are not sufficient – both of these things are too abstract. “People would be much more motivated if they knew precisely what could be achieved through their engagement”, says Egert. “For example, they could be informed that by sacrificing their own comfort, it will be possible to continue supplying the local school with electricity.”
This approach could be combined with nudging. Nudging is effective in many different sectors: It is already known, for example, that people will impulsively buy sweets in a supermarket if they are placed near to the cash till. If healthier dishes are placed in the same location, they are also purchased more frequently instead. Nudging has also proved to be helpful when users are asked to define a password on the Internet – some websites indicate how secure the selected password is while it is being entered by the user. Similar techniques could be used to highlight the consequences of the decisions customers make about their energy consumption. Another possible option is so-called gamification which utilizes principles found in video games: A consumer receives points for adapting their electricity consumption and they can then look to see where they stand in the local rankings – anonymously– with respect to their neighbours.
It is important for electricity suppliers to have a clear overview of not only their active customers and their preferences but also the possible costs of offering different supply tariffs and where possible negotiated feed-in remuneration for households that produce electricity. Operators must be able to quickly decide which resources they can utilize in the event of a shortage or surplus of supply. The framework conditions can be technically complex. For example, it is not advisable to always switch the same devices on and off because they could wear out more quickly. The physical proximity of consumers to the source of the power cut is also sometimes decisive.
We believe that the key lies in whether people have sufficient knowledge about the current electricity grid and the potential of the smart grid.
However, the biggest challenge is generating awareness about a resilient energy grid. “We believe that the key lies in whether people have sufficient knowledge about the current electricity grid and the potential of the smart grid”, says Egert. More knowledge creates a greater affinity for energy-related themes and motivates people to switch between their dual roles of consumer and producer. “Actively engaged consumers are also more receptive to the energy transition – and the more of them there are, the quicker the political decision-making process and the transfer of technology will tend to be”. Both of these things are indispensable for the resilience of the grid.
„Exploring energy grid resilience: The impact of data, prosumer awareness, and action“, Rolf Egert, Jörg Daubert, Stephen Marsh, Max Mühlhäuser. Patterns, Vol. 2, Issue 6, 100258, June 11, 2021 (Open Access)