Because somebody in Ukraine decided that Ukraine, at least, shouldn't supply the electricity:
The Russian government announced a state of emergency in the disputed Crimean peninsula late Saturday evening after power to the region was suddenly cut in an apparent act of sabotage in neighboring Ukraine.
You can't say Russia doesn't deserve that.
UPDATE: This is interesting:
Relations between Russia and Ukraine have further deteriorated as the countries clashed over gas and Kiev banned all Russian airlines from entering Ukrainian airspace.
The gas dispute will raise concerns that European supplies could suffer, and comes after the annexed Crimean peninsula was left without electricity at the weekend after saboteurs blew up power cables in mainland Ukraine.
Russia’s Gazprom said it would not ship any gas to Ukraine until it received prepayment. Later on Wednesday, Ukraine’s prime minister, Arseniy Yatsenyuk, claimed that he had ordered the state gas company to stop purchasing Russian gas. “It is not that they are not delivering us gas, it is that we are not buying any,” he said.
Yatsenyuk said Kiev had been offered a better price by other European countries, who import gas from Russia but could then send it back to Ukraine. Earlier this week, Ukraine’s energy minister said the country had enough gas in reserve to last through winter.
And the story reports that ethnic Tatars in Ukraine are trying to interfere with repairs to the electric lines in solidarity with Moslem Tatars in Crimea who oppose the annexation by Russia.
Note that Moslem Turkey is a natural champion of the Tatars.
Russia's Syria intervention isn't so much as a distraction from Ukraine as it is a link in a chain.
Russia wants Crimea to project power into the Mediterranean. Syria is the location of Russia's position in the Mediterranean. And Turkey lies between the two by controlling the Turkish straits, with interests in both Syria (from which forces could threaten Turkey's holdings in northern Cyprus and Turkish border regions claimed by Syria) and Crimea (and the Black Sea in general).
I wonder what Turkey and Ukraine talk about these days.