Apple is considering directly funding at least six Irish renewable energy projects, which could result in total new investment of more than €400 million. The facilities will power its planned €850 million new data centre in Galway.

The company has this week sought partnership proposals from developers for a number of new green energy projects, each of up to 50 megawatts capacity. Its data centre in Athenry will require capacity estimated at more than 300MW for services such as iTunes, Maps and Siri.

Apple did not specify the type of renewable energy, although onshore wind, currently popular with funders, would appear a likely contender.

A 2014 report by the energy consultants Pyory estimated the investment per MW of new wind capacity at about €1.5 million, suggesting total investment of up to €450 million if Apple powered the entire facility with windfarms.

In a tender on Ariba.com, Apple said it is “most interested” in agreements with developers to purchase electricity. It also indicated, however, it “would consider purchasing in their entirety such assets” once they come onstream.

If it chooses to enter a power purchase agreement, it will enter into contracts of up to 20 years duration. “Additionally, if there is an opportunity for an acquisition or investment by Apple, provide the structure pricing for such an arrangement,” it instructed.

The technology giant said proposals must be eligible for subsidies under the State’s REFIT program, which applies to onshore wind, hydro and biomass. Apple only wants projects within the Republic of Ireland, and they must be ready in 2017 or 2018. Those in “proximity to Athenry” will have an advantage.

The State is pitching Ireland to big technology companies as a top location for their data centres, as the climate here requires less air conditioning of the data farms, which expel significant heat.

The Irish Wind Energy Association,a lobby group for windfarm developers, said plans for more data centres here are a “vote of confidence that shows renewable energy is an enabler of foreign direct investment”.

"Ireland is a hub for these facilities. We know of a long queue of companies similar to Apple who want to build them," said Kenneth Matthews, IWEA chief executive.

Google and Microsoft are among those with Irish data centres, while Yahoo recently indicated it was considering such an investment.