Middle Eastern members of OPEC are finally diversifying their energy base, pouring hundreds of billions of dollars into harnessing that other resource they feature in vast quantities: sunshine.

But it isn't what you think. The Saudis, Abu Dhabi and Iran aren't racing to burnish their green credentials by reducing their carbon footprints. They are investing in solar-power production mainly for one reason: to help them export even more oil and gas.

'Logical Focus'

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