I doubt that it was Russian sabotage but would not be surprised if the Europeans try to pin it on them,after all that dastardly Putin blew up his own gas pipeline just so he couldn't sell the gas to Germany (makes sense right ? )
As already mentioned above the most likely cause is the unreliable nature of "green" energy if the sun don't shine (unusual atmospheric conditions ! 😋 )
or the wind don't blow then you need a backup supply which can be Hydro oil,gas and nuclear and they need to be enough to fully replace the "green" energy at a moments notice if not well we have just seen what happens.