In its annual environmental report, US technology giant Apple has detailed the various steps it takes to ensure its data centers are relatively environmentally friendly.

Apple’s data centers are 100 percent renewably powered - this is achieved primarily through power purchase agreements, but the company also uses direct access solar arrays, local micro-hydro projects, biomass facilities and more.

How Apple keeps its data centers clean

The Environmental Responsibility Report covering fiscal 2016 explains what it has done for each of its data centers:

Maiden, North Carolina

  • Between 60 and 100 percent of the Maiden data center’s energy use is generated by two 20MW solar arrays, an 18MW solar array, and 10MW of biogas fuel cells.
  • Apple partnered with local utility Duke Energy to build five solar projects, with a combined peak capacity of 20MW.
  • The data center uses outside air cooling, with a waterside economizer switching on at night and during the colder months of the year. This, combined with water storage, allows for chillers to be turned off most of the time.

Newark, California

  • Energy is sourced primarily from wind farms in California, acquired directly from the wholesale market through the state’s Direct Access program. Wide availability of wind power has meant that the facility has been powered by 100 percent renewable energy since 2013.
  • After the 130MW California Flats solar project in Monterey County comes online later this year, Apple will supply power from the solar field directly to the Newark data center as well as other Apple facilities in the state.

Prineville, Oregon

  • The data center’s energy needs are partially met by two “micro-hydro projects” that are powered by local irrigation canals. The projects generate 12 million kilowatt-hours of renewable energy per year.
  • Apple has signed a “long-term purchase agreement” with Cypress Creek Renewables to buy energy from a 50MW portfolio of six solar arrays in Oregon.
  • The company signed a 200MW power purchase agreement with a new Oregon wind farm, the Montague Wind Power Project. The first wind project established by Apple itself, it will produce more than 560 million kWh of renewable energy a year. The Montague Wind Power Project is expected to come online by the end of 2018. 
  • Finally, Apple has signed a power purchase agreement with the 56MW Solar Star Oregon II PV array, which is located “just a few miles” from the data center. When it comes online at the end of 2016, the site will produce 140 million kWh of renewable energy a year.

Reno, Nevada

  • Nevada’s energy industry is highly regulated (see: Switch’s suit against NV Energy), so “Nevada did not offer a simple solution for us to create new renewable energy projects dedicated to [the] data center,” Apple said. As a result, Apple turned to NV Energy to develop the Fort Churchill Solar PV project.
  • Apple said that it “designed, financed, and constructed the project,” although the actual designer was SunPower. NV Energy operates Fort Churchill and directs all the renewable energy it produces to the Apple campus. A 20MW array with an annual production capacity of over 43 million kWh, it uses photovoltaic panels with curved mirrors that concentrate sunlight.
  • At the end of 2016, a second solar array, the 50MW Boulder II project, came online in Nevada. Apple said it was made possible due to collaboration with NV Energy and the Nevada utility commission, creating a “green energy option open to all commercial customers that does not require the customer to fund project development up front.” Apple added: “We’re proud that another Nevada data center operator has also used the new green energy option, twice.”
  • The new option has been used to establish Techren Solar, a 200MW solar array project announced earlier this year. Set to produce 540 million kWh of power, it should come online by the end of 2018.

Mesa, Arizona

  • Apple partnered with local utility, the Salt River Project, to build a 50MW solar array called Bonnybrooke. Operational since October 2016, it produces over 147 million kWh of energy a year, “which more than fully matches the energy used by the data center.”

Viborg, Denmark

  • The data center is still under construction, but the facility is expected to run on 100 percent renewable energy.
  • Located near one of Denmark’s largest electrical substations, it won’t require back-up generators.
  • The facility will capture excess heat and use it for local district heating.
  • Apple is partnering with Aarhus University (Viborg campus) to co-develop an agricultural waste biomass project. “Methane from the biomass digester reaction will be used to create renewable electricity for our data center,” the company said. The agricultural waste will mostly come from local farms, which will benefit from the byproduct of the digester, nutrient-rich fertilizer.

Athenry, Ireland

  • This data center is still under construction - in fact, it has been repeatedly delayed due to local disputes. If and when it opens, the facility will also be fully powered by 100 percent renewable energy (primarily through power purchase agreements).
  • The facility will be cooled by natural ventilation, rather than mechanical air-conditioning.
  • Due to Ireland’s abundance of coastal waters, Apple has partnered with the Sustainable Energy Authority of Ireland to support new ways of capturing wave energy and converting it into renewable electricity.
  • As part of this agreement, Apple “supports a new wave energy technology” from SeaPower, which was tested near the location of the upcoming data center in Galway Bay last October. SeaPower says that its 1.5MW Power Take-off systems will be located at least 4 or 5 kilometers offshore.

Colocation facilities

  • In addition to its own data centers Apple uses third-party colocation facilities, but it says that it includes those in its renewable energy goals. “Over 99 percent of our power for colocation facilities is matched with renewable energy generated within the same state or NERC region for facilities in the United States, or within the same country for those around the world,” Apple said.
  • The company added that it worked with one of its main suppliers of colocation services to provide renewable energy solutions to all of its customers.


  • “We also use third-party computing services to support some of our on-demand cloud storage-based services,” Apple said. While it has never confirmed which providers it uses, it is thought that Apple turned to Google Cloud Platform in March 2016 for the majority of its cloud needs, with some services reliant on Amazon Web Services and Microsoft Azure. 
  • Google expects to achieve the goal of being powered by 100 percent renewable energy later this year.

The dirty bit

Of course, no matter how many solar arrays are built, data centers do occasionally need to turn to diesel-powered emergency back-up generators to keep things going. In a footnote, Apple revealed how much diesel it used over the course of the year - a total of 261,580 gallons.