Apple was reported as spending a hefty 500 per cent more on solar and now we know why, it's installing a floor that will harvest the power of the sun.

The Apple San Francisco Store will have a new solar glass walkway installed by OnyxSolar that is able to generate power to make the store 100 per cent renewable powered, claims electrek which spotted the deal.

The 130 module glass walkway will be able to generate over 90,000kWh of energy per year from solar power alone. This equates to offsetting 61 tonnes of CO2 per year.

Is this the start of a move to make all of Apple's buildings totally renewable? The new Apple Campus and Spaceship Office are going to be primarily powered by a solar system that churns out a whopping 5MW of power.

Tim Cook has previously expressed his desire for Apple to lead the way in eco-friendly design. He said: "We take the same innovative approach to the environment that we do with our products." Then, speaking directly to investors he pointed out: "If you want me to do things only for ROI reasons, you should get out of this stock."

How much Apple has spent on this setup is unclear but according to OnyxSolar documents it should pay for itself in just two years of power saving costs.

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