EU gas prices have spiked to historic highs, increasing 10-fold on the Dutch TTF in the last 15 months,

said Serhiy Makogon, the Director General GTS Ukraine Operator, wrote yesterday on Facebook. “Today at the European hub TTF, the price of gas with delivery next month crossed the border of 40 euros per megawatt-hour,” he wrote. “This is a historic maximum. And this is 10 times more than in May last year.”

This summer’s high gas prices will mean increases of 15-70% in winter heating bills for Ukrainians

, forecasts Ukrteplokommunenergo, the heating supply industry association. “If the price of gas continues to rise…we can predict growth [of bills] by 15-70%, depending on the region, city, local community, said Sergiy Dunailo, the Vice President of the association. Ukraine imports from Europe about 30% of its gas, overwhelmingly of Russian origin.

With Gazprom closing its Yamal-Europe pipeline tomorrow for a week of repairs,

Europe’s price of gas has climbed steadily reaching $450/thousand cubic meters. EU gas storage facilities are only 47.5% full — the lowest level in history and 15 points below the average of the last five years. With no price relief in sight, Nord Stream 1 closes on July 13 for 10 days of repairs. In previous years, Gazprom compensated for scheduled pipeline maintenance by sending more gas across Ukraine.