There is plenty of public discussion about the so-called ‘high electricity capacity’ that is moving through Elering’s grids and is seen as a priority. Less is said about the distribution networks that bring this electricity to our homes, even though it is the latter that determine the quality of everyday supply of electricity, writes the research portal Novaator.
Already in the next few years, 650 MW of solar power can be expected to be connected to the grid during the summer lunchtime hours, which the current electricity grid as a whole cannot absorb. To solve this problem, grid connection for small producers should be made fairer and local storage capacity requirements would also help, suggests Noman Shabbir’s PhD thesis* at Tallinn University of Technology.
Historically, Estonia’s distribution network has been structured in such a way that electricity can move well from producer to consumer. In the opposite direction, however, bottlenecks arise. But this opposite direction is increasingly needed. Nowadays, virtually every household that, until now, has only been a consumer of electricity in the traditional sense, can also become an energy producer, wishing to feed the electricity generated by it and left over from its own consumption back into the grid.
Shabbir’s thesis supervisor, Lauri Kütt, a senior lecturer at the Department of Electrical Power Engineering and Mechatronics at TalTech, said that the research was motivated by the realisation that Estonia’s distribution network is not very renewable energy-friendly. Something must be done to cope with the ever-increasing amount of solar electricity. Otherwise, we would soon be facing a failure.
The problem is further complicated by the fact that these small producers are predominantly involved in solar power. Its production peaks in summer for a fairly short period. This means that the large amount of electricity suddenly added to the grid may not fit into the distribution network. This is because the possibility was simply not taken into account when the network was built.
In his work, Noman Shabbir proposed that electricity producers should have a storage capacity at least equal to their own consumption. In addition, the management of such power banks should be set up in such a way that it does not only serve its own interests, but is able to store energy throughout the peak production period and to time its use to when it is needed elsewhere in the grid. In this way, the stored energy could also be used to stabilise the entire grid.
Other solutions proposed in the doctoral thesis of Tallinn University of Technology are available in the full article published in the Novaator portal.
*The research paper, authored by Noman Shabbir and supervised by Lauri Kütt, was awarded second place at the doctoral level in the field of engineering and technology at the 2022 National Contest for University Students.