(CNN) -- In the narrow winding lanes of Old Delhi, the knotted masses of electrical wiring hanging across the streets are sometimes so thickly entwined they blot out the sun. In the streets of Bangkok, electricity wires loop and run in chaotic bundles from concrete power poles. In the slums of Mumbai to the townships of South Africa, electricity infrastructure is a triumph of make and mend. For power utilities in emerging markets, collecting the bills from this tangled skein of wiring is a nightmare and slow payment - even outright energy theft - remains a powerful disincentive for new investment in the sector.
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The city of Tshwane in South Africa is installing pre-paid electricity smart meters
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The city has endemic problems of late payment, long-term debtors and electricity theft
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It's hoped smart meters will bring much-needed investment in the sector
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Poor electricity infrastructure in places like Africa or India makes energy theft easy
So far, some 3000 smart meters have been rolled out in @placeholder, particularly among high consumers of energy.