The environmental movement has shown no signs of slowing down nearly half way through 2018. In advance of Earth Day, Apple announced that it was going full clean energy, powering all of its offices, data centers, and stores with a variety of environmentally-friendly power sources. Apple also wrangled some of its suppliers into committing to 100% clean energy, too.

Apple and other tech companies have gone to great lengths to project an awareness of the environmental impact of their business models. Many now release yearly “Environmental Impact” reports and one-up each other with admirable strides toward cleaner technology use.

But the reality, as a number of environmental organizations continue to point out, is that most of these companies are reliant on a business model that requires consumers to buy new phones, laptops, and tablets frequently. And that creates a lot of waste.

SEE: IT Data Center Green Energy Policy (Tech Pro Research)

The problem has little to do with how we use a device and more to do with how we acquire it and get rid of it. There are more than 65 million metric tons of e-waste worldwide now, yet 70-80% of the energy footprint of a device occurs during manufacturing, according to Greenpeace.

The manufacturing of these devices, which occurs mostly in China and Southeast Asia using products mined in dangerous conditions across the globe, requires extensive waste and coal burning. Some companies are beginning to address this, with new recycling programs and energy-conscious supply chains. Here are the five greenest tech giants, as ranked by Greenpeace.

1. Apple

When it comes to going green, Apple has had a very successful year so far, after facing heavy criticism last fall following allegations that it may have intentionally degraded the batteries in their phones. Apple has been more transparent than many companies about its supply chain and the need to make it more energy conscious. They have invested more in recycling programs that can harness some of the materials needed for devices outside of the mining process.

Their massive data centers are powered 100% by renewable energy, according to a press release. They have come out in support of the Paris Climate Agreement and have worked to root out child labor issues amongst larger efforts to move to a closed-loop supply chain.

2. HP

HP is one of the few companies striving to do the opposite of most other tech companies. Oversaturated markets have forced some companies to make products that degrade quickly. According to Greenpeace, the average smartphone lasts only two years now, forcing users to buy new models with increasing frequency. But HP, along with Dell and a few others have moved in the opposite direction, making products that do stand the test of time and are upgradeable.

SEE: Green tech initiatives: Best practices and breakthroughs (free PDF) (TechRepublic)

HP set concrete goals on reducing emissions throughout their supply chain and actually publish a list of materials that they restrict during the manufacturing process. The company claims to have seen a 21% reduction in greenhouse gas intensity in its supply chain since 2010, and has been able to strong arm more than 90% of its suppliers into setting emissions targets.

In addition to their internal efforts, HP also backed the Paris Climate Agreement. According to their Sustainability report in 2016, HP has worked hard to bring their consumption down to 900,000 tons of materials used in 2016 for products and packaging and 119,900 tons of equipment collected for recycling.

3. Dell

Dell is one of the only major tech companies that openly provides a detailed and extensive list of suppliers in addition to what kind of services were rendered for each deal. Like HP, they are bucking the trend and making devices that are lasting longer and easily upgradeable. When it comes to their plastic use, its on a closed-loop, so anything used is recycled and reused. They claim to reuse more than one third of the plastic involved in their manufacturing process.

The firm heavily markets their refurbished devices and laptops, designing them specifically with repair in mind. Dell also sells spare parts widely, and releases extensive manuals on how to repair their laptops and tablets. Due to a reliance on cobalt, they have worked with authorities to clear their suppliers of child labor. Transparency has been one of Dell’s major focuses, and they worked to identify, contain, and limit the use of dangerous chemicals necessary for their devices.

4. Microsoft

Although it has been on the receiving end of criticism for the short lifespan of its devices, Microsoft has been public about its support for green initiatives, backing the Paris Climate Agreement and the Clean Power Plan. The company also supported environmental efforts in Japan.

The repairability of their devices can range widely, but they have a robust offering of refurbished devices and do report some of the materials used in the manufacturing process. They have also been working to make their data centers more environmentally conscious as they expand across the globe, as noted in a blog post. The targets for emissions they have set are lower than those of Apple, but they are one of few companies to actually set any goal at all.

Many of the company’s products and suppliers are listed in an effort to combat trafficking or child labor within their supply chain.

SEE: CBS News finds children mining cobalt for batteries in the Congo (CBS News)

5. Lenovo

Lenovo has worked hard to surpass its Chinese peers by presenting clear plans demonstrating how it will cut its emissions, which are growing steadily each year. They provide a detailed snapshot of their greenhouse gas emissions and carbon footprint, according to a recent sustainability report.

Lenovo has also committed to ending its use of certain hazardous chemicals and recycles some of the plastic used in its manufacturing process, the report said. The company has worked to sell lines of refurbished devices and controls nearly 20% of the global laptop market.

As noted in the report, Lenovo made a commitment to cut greenhouse gas emissions in their own operations by 40% before the year 2020. When it comes to their suppliers, they have forced most to set some emissions goals, but could do more.