As indications of climate change intensify and the world ponders the future of the Paris Agreement under the Trump presidency, every commitment by governments and businesses to combat this problem assumes additional significance. The announcement this month by Google, the world's leading internet services company, that it would by 2017 meet 100 percent of its corporate energy demand from carbon-free sources is therefore a critical signal of the corporate world's commitment to responsible environmental stewardship. Google's efforts are driven not just by a notion of corporate responsibility but also by business imperatives: Going green is smart, efficient and potentially profitable. That is the way to ensure that such policies are adopted more widely.

Google (or more accurately its parent company, Alphabet) is the world's second-largest corporation by market capitalization: It is worth more than $530 billion. Headquartered in the United States, it has a digital and physical footprint that stretches around the world; in addition to office complexes that house staff and scientists, the company has huge data farms dotted across the globe. Those farms house massive computing facilities that consume extraordinary amounts of energy. It is reckoned that Google consumed 5.2 terawatts of energy in 2015 — the equivalent of the energy needs of the city of San Francisco or half a million homes in the U.S.

In a bold move, Google announced in 2012 that it was committed to 100 percent renewable energy purchasing in its operations. This month it confirmed that it will by 2017 purchase enough green energy to meet all its energy needs. Currently, the company has commitments to purchase 2.6 gigawatts of electricity under long-term contracts, an increase from 2 gigawatts just the year before. This amount will match the energy Google consumes during a year of operations and make Google the largest corporate purchaser of renewable energy in the world — larger even than many utilities.