Microsoft wrapped up what it says is the largest single corporate purchase of solar power in the US to date with a 315MW PPA for output in Virginia.

The IT giant will take the power from the Pleinmont I and II projects, part of a wider 500MW development planned by sPower.

Microsoft has a large footprint of facilities in the state and said the deal brings its total of directly contracted renewable energy to 1.2GW.

The software group, which recently signed its first deal for solar output in Asia, is working towards a goal of a 60% renewable power share at its data centres by 2020.

The Microsoft PPA – the term length of which was not disclosed – is the latest in a string of increasingly large corporate renewable energy deals being struck by US tech giants and other major corporations.

Corporates signed a record 5.4GW of clean energy contracts last year, with 2.8GW of that sealed in the US, according to data from Bloomberg New Energy Finance.

Just a few days earlier Facebook signed an expanded deal to take the full output of Enel’s 320MW Rattlesnake Creek wind farm in Nebraska.

sPower – a pioneer in US solar development that is also expanding in wind – said the Microsoft deal was a “game changer” for the Virginia developments, for which no construction schedule was given.

CEO Ryan Creamer said: “Their early commitment helped ensure that the project continued to move forward and come to fruition at a time of regulatory uncertainty. Microsoft’s large off-take also helped us offer very cost-competitive options for other buyers looking at our Virginia portfolios.

“This model broadens the ability for buyers of all sizes to participate in a large project like this, yet only take the megawatts they need for their business goals.”