According to "Power Forward 3.0," the latest in a series of reports on corporate involvement in green initiatives, published by the World Wildlife Fund (WWF), the largest companies in the United States are steadily increasing their clean energy and energy efficiency efforts, and improving their bottom lines at the same time.

"Overall, nearly half of the companies in the 2016 Fortune 500 have set targets to reduce greenhouse gases, improve energy efficiency, and/or increase renewable energy sourcing—up five percentage points from our last report in 2014," states the report.

The strongest efforts are being undertaken by the Fortune 100 companies, with 63 percent adopting or retaining goals. The report also shows strong improvement among the smallest 100 companies in the Fortune 500, with 44 percent of these setting goals in one or more categories, up 19 percentage points from 2014.

The most significant new trend among the Fortune 500 since the last report is the increasing ambition of goal setting, as more companies move to establish science-based targets and set 100 percent renewable energy goals. Almost 50 percent (48 percent) of Fortune 500 companies now have climate and/or energy targets.

Companies are also doing well in meeting their targets. On average, companies reported an 81 percent success rate in achieving or exceeding their targets on time.

Attracted by plummeting renewable energy costs, almost two dozen Fortune 500 companies have committed to power all of their corporate operations with 100 percent renewable energy (mostly wind and solar).

Fifty-three of these companies are setting renewable energy goals, up from 42 companies in 2014. Of those setting public renewable energy goals, 23 companies have staked out leadership positions with commitments to 100 percent renewable electricity goals.

Pursuing and achieving clean energy targets and goals are yielding financial benefits for these companies. Almost 80,000 emissions-reducing projects have led to $3.7 billion in savings by 190 companies in 2016 alone.