The Grid4EU initiative recently released its final report, and so the time is right for a review of what is one of the biggest and most comprehensive smart grid demonstrations, certainly in Europe, to date.
Some headline figures for the 4-year project include the involvement of 27 organizations from 15 countries, including six of the largest Distribution System Operators (DSOs) – together covering more than 50% of metered electricity customers in Europe – each running demonstrators directly involving a total of 275,000 consumers. The cost, €54 million, of which half was supported from the EU’s FP7 research programme.
Clearly Grid4EU – which was awarded the ISGAN’s 2015 Excellence in Smart Grids award - involved considerable effort, much more than comes through in the 246 page report. Commenting on the results, the words of coordinator Rémy Garaude Verdier sum them up well: “We are all proud of them.”
Grid4EU was developed as a large-scale demonstration of advanced smart grid solutions with wide replication and scalability potential for Europe.
The six DSOs leading the project were ERDF in France, Enel in Italy, Iberdrola in Spain, Distribuce in Czech Republic, RWE in Germany and Vattenfall in Sweden. Coordination was by ERDF while Enel was technical director and Iberdrola chairman of the General Assembly.
The initiative aimed at testing innovative concepts and technologies in real-life environments, in order to address barriers to the deployment of smart grids in Europe. It focused on how DSOs can dynamically manage electricity supply and demand. The main topics addressed are:
• Improvement of MV and LV network automation technologies to face the constraints introduced by increasing amounts of distributed resources and new usages (e.g. electric vehicles, heat pumps), to reduce energy losses and maintain or increase quality of supply
• Integration of an increasing number of small- and medium-sized distributed resources (PV, wind, combined heat and power, heat pump and storage)
• Balancing of intermittent energy sources with demand response and different storage technologies and services
• Assessment of islanding as a solution to increase grid reliability
• Increasing use of active demand including potential new usages and evolving customer behaviours.
The demonstrators are briefly outlined in the diagram below.
Grid4EU developed 67 technologies and possible applications with potential for scaling up, with nine key findings.
1. Solutions related to voltage and load control are beneficial resources to increase network hosting capacity in European distribution grids.
The advanced control of On Load Tap Changer at MV level in the Italian demonstrator and at MV/LV level in the French demonstrator is a major resource for increasing the hosting capacity. The grid reconfiguration approach tested in the German demonstrator also offers high potential for increasing network hosting capacity.
2. The scalability and replicability analyses performed point out that the interaction of distributed generation and demand curves is also a key aspect to increase the network hosting capacity. While depending mainly on the type of consumers and distributed generation technology, energy storage and flexible demand can help increase network hosting capacity.
Grid storage tested at MV level in the Italian demonstrator and at LV level in the French demonstrators, when correctly sized, was able to contribute effectively to voltage regulation and grid power flow control and thus increase network hosting capacity. This tool turns out to be easy-to-use and programmable. However, it is still too expensive when used only for distribution service.
3. The scale of residential and industrial flexibilities is inherent to the local customer engagement level, which in turn is strongly related to the local context. The high recruitment and commitment levels (in comparison to other pilots) achieved in Grid4EU may not be scalable.
Beyond the willingness to decrease the bill, the opportunities to act in favour of the environment and to contribute to improving the security of supply turned out to be major drivers. In the Spanish demonstrator, around 80% of the participants in the Customer Engagement programme changed their consumption habits.
In terms of engagement, customers tend to be more active at the beginning of the programme. For example, in the Spanish demonstrator 65% of customers stated they looked at the in-home display (IHD) more than once a day at the beginning, but in the long term only 30% used the IHD daily.
4. Fault localisation and restoration time can be further reduced in Europe through more automation at MV and LV levels.
The enhanced observability of the LV grid, enabled in the Swedish and Spanish demonstrators, is the first step towards grid automation. Grid automation, particularly at MV level, has a significant impact on frequency and duration of interruptions. The German demonstrator showed that the autonomous switching system providing dynamic topology reconfiguration of the MV grid has the potential to halve the time of fault localisation, isolation and restoration. The automated failure management solutions tested in the Spanish and Czech demonstrators have the potential to improve SAIDI. The automatic failure management at LV level also tested in the Czech demonstrator is technically possible and could reduce SAIFI and SAIDI but is not yet cost effective.
5. Automation at LV and MV levels also open up further levers to decrease energy losses.
Solutions dealing with the planning phase of the network, like grid reconfiguration in the German demonstrator, tend to strongly decrease losses. During the operation phase, the losses can also be reduced, but the total amount depends on the available resources. The solution tested in the Italian demonstrator, reducing losses due to the combined modulation of the bus-bar voltage and reactive power flow, also achieves a slight reduction of the losses. The use of storage systems (whose losses were measured in the French demonstrator) can also reduce network losses but usually tends to increase the losses because of the internal losses of the storage system.
6. For higher grid resiliency, it is technically feasible to operate the grid in islanding mode for more than 4 hours, while complying with requirements for continuity of supply.
In the Czech demonstrator, islanding was performed with a combined heat and power (CHP) unit. In the French demonstrator, the islanding was performed without any rotating generator inside the islanding area (only PV generation and electric storage). Two islanding processes, black starting and switching, were successfully developed and implemented.
7. It is necessary to foster “convergence” between electric distribution and communication infrastructures.
At this stage the maturity of the smart grid community tends to be high in the lowest layers of the Smart Grid Architecture Model and rather low in the highest layers.
8. Smart grids are not only technologies and the “human component” is of paramount importance.
With its scale Grid4EU needed huge coordination efforts. The active involvement from the beginning of the users of the smart grid solutions, whether the partners’ workers or customers, is key to enable the appropriate execution of these solutions.
9. A multi-site and multi-system project is an asset for large-scale information dissemination.
Major events, workshops and publications have all contributed to knowledge sharing on smart grids at the global scale, largely facilitated by the diversity of solutions implemented in Grid4EU.
The French demonstrator Nice Grid will be explored in detail in Engerati’s In Focus programme Nice Grid - A smart solar district starting 31 August.