The Challenges Of Managing Renewable Power

Europe is running into a situation of paying people to use power (h/t Ritholtz):

The 15 mile-per-hour winds that buffeted northern Germany on July 24 caused the nation’s 21,600 windmills to generate so much power that utilities such as EON AG and RWE AG (RWE) had to pay consumers to take it off the grid.
Rather than an anomaly, the event marked the 31st hour this year when power companies lost money on their electricity in the intraday market because of a torrent of supply from wind and solar parks. The phenomenon was unheard of five years ago.
With Europe’s wind and solar farms set to triple by 2020, utilities investing in new coal and gas-fired power stations no longer face stable returns. As more renewables come on line, a gas plant owned by RWE or EON that may cost $1 billion to build will be stopped more often from running at full capacity. It may only pay for itself on days like Jan. 31, when clouds and still weather pushed an hour of power on the same-day market above 162 ($220) euros a megawatt-hour after dusk, in peak demand time.

It would seem like pumping water to fill elevated reservoirs or some other fairly inefficient storage solution would be preferable to this scenario.  What about water electrolysis to store hydrogen for use in a fuel cell or something?  This would seem like the same kind of issue nuclear plants have run into over the years, but it is hyped more because it is renewable.  Overall, it seems like a very solvable problem to have.