Researchers have railed against the bigger-is-better vision to realise the dream of a solar-powered data centre opting instead for a less-is-more approach to overcome efficiency hurdles.

Apple is building a 40-hectare solar farm to power a green data centre, generating 20 megawatts. Meanwhile, Facebook has installed a 100kW array to generate electricity for its data centre in Prinville, Oregon.

More than 500 square metres of solar panels sit on the roof of IBM India's Bangalore offices, where energy from the searing subcontinental sun is converted into 50kW of electricity.

However, only a handful of technology giants can afford to connect solar panels on such a huge scale. For the remaining companies and consumers, the dream that the sun can solve the world's energy problems has been grounded by solar power's fundamental weakness: it can't match the power of electricity generated and distributed on the grid.

One major hurdle is the requirement to convert the electric current generated from the sun's rays. Solar panels naturally generate DC but this is usually converted to AC — and back to DC — at various points in the supply chain. So the electric current has weakened by the time it reaches the final product or, in this case, processor.