Many years ago, I thought we should be using hydrogen as stored electricity. Generate as much as possible when the sun shines and wind blows. Use excess electricity to make hydrogen. Store it in a big tank. Convert the tanked H2 into electricity when the renewables aren't as productive.

Hydrogen plants:

http://www.tiereddemocraticgovernance.org/blog_details.php?blog_cat_id=27&id=38

And yep, a hydrogen explosion is not as bad other kinds of explosions.