100% renewables for their data centers. In the same way that Apple's total power is still partly dirty I'd think some of their offices won't be running entirely off the grid.
Apple is making great strides towards getting their offices off the grid as well. Their new campus has a considerable amount of solar deployed on-site plus they're partnering with other companies to provide power from off-site.
From Google's 2016 energy report: "And in 2017 Google will reach 100% renewable energy for our global operations..."