Apple is staying true to its promise to move to 100% renewable energy, putting plans in place for a large solar farm in Reno, US, where it is building a giant data center.

It is working with local utility NV Energy to build the solar farm in Northern Nevada on 167 acres of land which will provide 18 to 20MW of power for its data center in the Reno Technology Park, managed by the Unique Infrastructure Group.

In an earlier interview with FOCUS, Unique Infrastructure Group CTO KC Mares said Apple is looking for a “strong mix of renewables” at the site.

“They’ve also considered installing renewable-energy infrastructure at the Reno Technology Park,” Mares said.

The park itself has earmarked room for 20MW worth of solar capacity at the site and Apple will now use this 137-acre piece of land to build its array – called the Ft Churchill Solar Array - adjacent to its data center.

The array will use a special mirror technology, according to 9to5mac, that increases the amount of light it can capture by seven times that of farms using solar arrays on their own.

The solar array is expected to produce 43.5m kW of energy. Excess energy can be sold back to the energy company for the local grid.

Apple said it also plans to use geothermal energy to make up its planned 100% renewable energy mix at Reno.

The Reno data center will be Apple’s largest facility with 15MW being planned for launch this year, a figure that will increase by 5MW a year until it reaches 35MW in 2015-2017.

In Apple’s 2012 environmental report it said the Reno data center will be built to be as environmentally responsible as its Maiden data center, which Apple claims uses the US’s largest end user-owned on site solar photovoltaic array.

This 20MW farm, situated on  100-acres, can provide 42m kWh of renewable energy which will double in capacity with the construction of a second 20MW solar photovoltaic plant nearby that will be operational later this year.

Apple also built a 4.8MW fuel cell that provides 40m kWh for the site and expects to increase this to 10MW in future.