Tech-savvy users are adding more and more data to remote online storage every day. But what else are they putting into the cloud? A lot of smoke and grime from non-green fuel, according to a new Greenpeace report.

The report, "How Clean is Your Cloud?", ranked Apple (AAPL) and Amazon (AMZN) among the worst of 14 companies in categories that included energy efficiency and infrastructure, but also in their unwillingness to publicly disclose energy data or talk about plans to improve it.

The report said Apple's iCloud service didn't rely enough on clean sources of electricity. Amazon and Twitter received even worse overall grades. Hewlett-Packard (HPQ), IBM (IBM), and Oracle (ORCL) were among other bad performers, while Google (GOOG), Dell (DELL), Yahoo (YHOO), and Facebook were the best performers.

Public image is becoming an increasingly important factor for major corporations these days, especially in the hyper-competitive world of technology. Last year, Apple faced scrutiny and threats of a consumer boycott following reports of malpractice and labor exploitation at its Chinese manufacturing factories. In March, after an independent audit found proof of unfair working conditions, the company announced immediately that it would work on changing its systems.

For a company like Apple, image is everything, so it should come as no surprise the tech giant was quick to react to the latest environmental report. "They are very brand-conscious companies," Gary Cook, the lead author of the Greenpeace report, told New York Times. "They want to be presenting themselves as responsible and innovative."

Apple said the figures Greenpeace used in its analysis were incorrect, but the independent environment protection organization said Apple had been given the opportunity to provide the right figures and did not.

Apple was faulted largely for its apparent lack of effort to use renewable sources of energy to power its data centers. The report estimated that the company got about 55% of its electricity via coal, with its main data center in Maiden, N.C., receiving most of its power from Duke Energy's (DUK) coal plants. Duke also fought back, saying the majority of its power now comes from cleaner nuclear energy.

Apple added that the Maiden data center only consumes 20 megawatts annually, less than the 100 megawatts that Greenpeace estimated. It also said that plans to power 60% of the center through a solar farm and a biogas fuel cell installation were progressing rapidly.

Apple, set to announce its second-quarter earnings next week, relies heavily on sales of devices that provide user access to the iCloud. Apple is thought to have sold almost 30 million iPhones and 13 million iPads over the last three months.

Amazon's Web Services got two F grades from Greenpeace for transparency and use of renewable energy sources. However, the organization appreciated Google's energy unit, which plans to buy wind power from NextEra Energy (NEE), adding in its report that Google had plans to source 35% of its energy from renewable sources. Greenpeace also appreciated that Google was involved in lobbying for clean energy policies in the country.

Greenpeace's report also praised Yahoo's new data center in upstate New York, which draws on hydro-power, and Facebook's center in Sweden that can run entirely on renewable energy.

In 2010, a Facebook-powered campaign against oil company BP (BP) after the Deepwater Horizon spill had consumers turning away from the company's gas stations. According to one estimate, sales for major BP distributors and retailers fell 10% to 30% early in the crisis. 

Consumer opinion also seems to have moved coffee retailer Starbucks (SBUX), which announced plans on Thursday to stop using insect extract as food coloring after receiving hundreds of petitions.

Even Hollywood has involved itself in campaigns against unethical environmental and labor practices, calling even greater attention to companies' missteps. Actor Ryan Gosling has been advocating for a charity that raises awareness about illegal activities associated with the mining of materials in the Congo used in electronics. The charity, Raise Hope for Congo, names Canon (CAJ) and Panasonic (PC) among the worst in taking action.

In fact, Raise Hope for Congo ranks many major technology companies, placing them each in one of four categories: a gold star for those considered "conflict-free"; green for "on the right track"; yellow for "room for improvement"; and red for "falling behind."

Not a single one of the 21 major technology companies rated by Raise Hope for Congo -- including Research in Motion (RIMM), SanDisk (SNDK), and Motorola (MMI) -- received a gold star. Dell, HP, Intel (INTC), Microsoft (MSFT) and Nokia (NOK) are the only six to be categorized as "on the right track."

Apple falls in the yellow category, which encompasses companies that have "taken some steps to investigate their supply chains, and are members of the industry-wide effort, but more action is required of them."

While Apple has built its reputation on quality products, the more environmentally and socially conscious consumer now threatens the company's dominance. Apple faced mass protests in Europe this week when Greenpeace activists staged an hour-long demonstration on the roof of the company's continental headquarters in Cork, Ireland. The protestors placed signs with letters spelling out the words "clean our cloud" and handed out pamphlets to company employees. Demonstrations were also said to have been held at Apple facilities in Turkey and Luxembourg.

With another public relations nightmare for Apple just as the Foxconn controversy had begun to wane, it's no wonder investors have become cautious. Though Apple shares are still up nearly 46% so far this year, they've actually declined 2.48% in the last month. One wonders when this trend will begin to show itself in sales. Quick action -- like that taken this week by Starbucks -- is necessary if Apple is going to maintain its once-pristine public image, an image that has made Apple products some of the most sought-after in the world.

Aabha Rathee is a writer at Wall St. Cheat Sheet. As of this writing, she did not own a position in any of the aforementioned stocks.

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