Apple is offering free recycling of all its used products and vowing to power all of its stores, offices and data centres with renewable energy to reduce the pollution caused by its devices and online services.

The iPhone and iPad maker is detailing its efforts to cultivate a greener Apple company in a new environmental section on the company's website.

The site highlights the ways that the company from Cupertino, California, is increasing its reliance on alternative power sources and sending less electronic junk to landfills.

Apple has already been distributing gift cards at some of its 420 worldwide stores in exchange for iPhones and iPods still in good enough condition to be resold. Now all of the company's stores will recycle any Apple product at no charge.

Gift cards will not be handed out for recycled products deemed to have little or no resale value.

The offer covers a wide array of electronics that are not supposed to be dumped in landfills because of the toxins in them. In the past seven years, Apple has sold more than a billion iPhones, iPods, iPads and Mac computers.

The new initiative, timed to coincide with tomorrow's annual celebration of Earth Day, strives to position Apple as an environmental steward amid the technological whirlwind of gadgets and internet services that have been drawing more electricity from power plants that primarily run on natural gas and coal.

Technology products and services accounted for about 2% of worldwide emissions in 2012, roughly the same as the airline industry, according to statistics cited by Greenpeace in a report released earlier this month.

Some of biggest electricity demands come from huge data centres that house stacks of computers that process search requests, store photos, and email and stream video.

These online services, often dubbed "cloud computing", collectively consume more electricity than all but five countries - China, the US, Japan, India and Russia.

As the world's largest technology company, Apple is trying to hatch more environmental solutions than problems.

Lisa Jackson, Apple's vice president of environmental initiatives, said: "What the company wants to do is use all our innovation and all of our expertise to make the planet more secure and make the environment better."

Ms Jackson ran the Environmental Protection Agency under President Barack Obama before joining Apple last June.

Apple chief executive Tim Cook underscored the commitment by narrating a short video about the company's efforts to protect the environment. "To us, better is a force of nature," Mr Cook says.

The campaign appears to be more than just a public relations stunt, based on Greenpeace's high praise for Apple in its recent review of the technology industry's environmental responsibility.

Among the 19 companies covered in the report, Greenpeace described Apple as "the most innovative and most aggressive in pursuing its commitment to be 100% renewably powered."

Greenpeace also gave high marks to Apple rival Google and to Facebook, which makes one of the most popular apps on the iPhone and iPad.

All four of Apple's data centres - in North Carolina, Oregon, Nevada and California - already rely entirely on renewable energy, the company said. The electricity comes from a variety of alternative sources, including biogas, as well as wind, solar and hydro power.

About 94% of the power in Apple's offices in the world is now supplied by renewable energy sources, up from 35% in 2010, according to the company.

Apple is building a new headquarters in Cupertino that will be powered solely by renewable energy when it is completed in 2016.

About 120 of Apple's US stores, or nearly half of the outlets in the country, run entirely on renewable energy.

Sign up to our free newsletters

Get the best updates straight to your inbox:
Please select at least one mailing list.

You can unsubscribe at any time by clicking the link in the footer of our emails. We use Mailchimp as our marketing platform. By subscribing, you acknowledge that your information will be transferred to Mailchimp for processing.