Well, the gas knew an incredible outbreak in the summer, with its peak in August, which had a direct consequence on the wholesale price of electricity during this period. At the origin of this outbreak, the concerns related to the shutdown of the Nordstream gas pipeline, combined with the fact that the European States wanted to guarantee their energy supplies for the winter and bought accordingly: the disproportionate demand compared to the supply caused already very high prices to soar: the peak of 350 euros per MWh for gas at the end of August is 17.5 times more than the June 2021 price.
The quarterly indexing system means that this huge increase is reflected in the variable contracts, from October 2022, and at least for the whole quarter. We can see it: for gas, the index has almost doubled, for electricity, it has more than doubled!
This slight difference is explained by the fact that for gas, it is the September price which is envisaged, whereas it fell slightly after the August peak, while for electricity, it is the average for the quarter (July-August-September), peak included, therefore, which is envisaged.