Apple is producing more than 200 million electronic devices each year. And making all those iPhones, MacBooks and tablets takes an enormous amount of energy.

That's why it's a big deal when Apple (AAPL) says it wants to be the greenest company on Earth.

The company launched a massive clean energy program in October 2015. The goal was to convert all of its energy use in China to clean power sources.

Apple clobbered past that goal and is now working toward 100% renewable energy worldwide.

"In 2016, 96 percent of the electricity used at our global facilities came from renewable energy, reducing our carbon emissions by nearly 585,000 metric tons. We're 100 percent renewable in 24 countries -- and all of Apple's data centers," Lisa Jackson, Apple Vice president of environment policy, said in an annual letter released earlier this year. Jackson served as the administrator for the Environmental Protection Agency from 2009 to 2013.

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To go fully green, Apple has said it plans to "generate and source from more than 4 gigawatts of new clean energy worldwide by 2020," according to a document released this month.

So far, Apple is less than a quarter of the way toward its 4 gig goal, the equivalent of the energy needed to power about 4 million homes. It currently has 485 megawatts of wind and solar projects installed across China.

The company also said last September that it's committed to making sure all of the companies that supply parts to Apple follow its lead. Seven of Apple's suppliers have already committed to going 100% renewable by 2018.

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Not to mention Apple's new corporate headquarters, Apple Park, will be powered solely by renewables. And to save trees, the company says 99% of the paper used in product packaging is from recycled materials.

Tom Murray -- the vice president of the Environmental Defense Fund's EDF+Business initiative -- praised Apple's efforts. He says Apple has been a leading player in sustainable initiatives, and now more than 70 companies have followed suit by committing to use only renewable energy sources.

"For companies like Apple, usually 80 percent or more of the carbon footprint is in the supply chain. That's why its critical that Apple is looking beyond its own operations and working with suppliers to become 100 percent renewable as well," he said.