Is anyone discussing _reliability_? as in Google/Apple/etc are making this move not just "to be green" but to ensure that they do have power without being subjected to the whims & issues of providers when they're just one of many customers? When you have literally hundreds of millions (billions?) of customers, you want to ensure your own resources are absolutely reliable (within your, not someone else's, requirements).

It's like me wanting to put solar panels on my roof: I'm not so much interested in cost savings, but want to ensure a massive grid failure doesn't take my household with it.