Pay as You Go Solar

Targeted toward people in poor countries, this power supply, sold with a photovoltaic panel, provides electricity only after the user sends a code from a prepaid card over a mobile phone. The code unlocks the system until a set number of kilowatt-hours is consumed. Users buy cards until the cost of the entire system has been paid off, after which it unlocks permanently.
Product: Simpa solar energy system
Cost: Starting at $150
Availability: January 2012
Source: www.simpanetworks.com
Companies: Simpa Networks
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