Perhaps the term "Holy Grail" is too sensational and carries far too many expectations even though energy storage is a huge issue for any technology going forward. We should use it in a watered down version.

The safe and useful storage of electricity is a tough nut to crack. But, there are considerably more dollars flowing into energy storage now, than ever before. Countries and many companies are showing a commitment to it.

The failure, (or extreme cost) of carbon capture continues to put pressure on oil and coal.