Solar eclipse of March 20, 2015: What impact on Belgian and European electricity networks?
The partial eclipse of March 20, 2015 could represent an important test for European network operators and for the coordination among them. Indeed, Friday's partial eclipse will imply a sudden shift in photovoltaic production (a reduction followed by a rapid rise of production) which might potentially disturb the European electricity network.
A partial eclipse impacting photovoltaic production
On March 20, a solar eclipse will cross Europe between 8h and 11h UTC. It will be total in northwestern Europe and off the coasts of the United Kingdom and Norway, and partial in the rest of Europe (80% moon coverage of the sun in Brussels).
Figure 1: Animation of the transit of the solar eclipse in UTC time
That eclipse, one of the most important since 1999, drew considerable attention from European electricity network operators, especially in view of the strong development of photovoltaic facilities in several European countries as well as the connections between national networks.
Figure 2: Installed photovoltaic capacities per country
European coordination and impact in France
The ENTSO-E, which represents numerous network operators in Europe, published a study on the impact of the eclipse in February . The results show that, with clear sky, European production would fall by around 20 GW during the first hour of eclipse and would increase by more than 35 GW during the last hour.
In Belgium, installed photovoltaic capacity is estimated at 3.2 GW on December 31, 2014 . That capacity is relatively low compared with the 39.7 GW installed in Germany.
However, photovoltaic energy plays a significant role nowadays in national forecasts carried out by transport and distribution network operators. Besides, a sudden shift in photovoltaic production could have substantial consequences on the local network, in areas where numerous photovoltaic facilities are concentrated.
At national level, a decrease of production is expected at maximum eclipse, varying between 280 MW and 1.32 GW according to meteorological conditions .
Figure 3: Impact of the eclipse on photovoltaic production in Belgium
Feedback about the experience of 1999 eclipse leads network operators to also pay attention to electricity consumption variations during the eclipse. On the one hand, an important part of the population could suspend their usual activities to observe the eclipse. That behaviour could produce a drop of consumption during the phenomenon, which would then offset part of the lack of photovoltaic production. The ENTSO-E study even mentions that those impacts would be stronger than the fall in PV production in the United Kingdom. On a behavioural viewpoint, the eclipse could also encourage the population to turn on the lights to compensate for the loss of luminosity.
On the other hand, the 1999 eclipse had an effect on outdoor temperatures: from -3°C to -5°C during the eclipse and -1°C until 12 hours after the end of the eclipse . In this way, knowing the influence of temperature on electricity consumption, especially in winter, the impact on consumption could last in the hours following the eclipse.
Sia Partners - Pierre Leplatois and Nicolas Taillard
NASA animation NASA of the eclipse transit: http://eclipse.gsfc.nasa.gov/SEplot/SEplot2001/SE2015Mar20T.GIF
Data from Solar impact analysis study - ENTSO-E: https://www.entsoe.eu/Documents/Publications/SOC/150219_Solar_Eclipse_Impact_Analysis_Final.pdf
Solar impact analysis - ENTSO-E : https://www.entsoe.eu/Documents/Publications/SOC/150219_Solar_Eclipse_Impact_Analysis_Final.pdf
Study carried out based on usual national PV production curves in March , on regional PV power data from the wind-PV dashboard of the General Commission of Sustainable Development and on NASA data about the eclipse.