... W/m2.162 Sustainable Energy Harvesting Technologies – Past, Present and Future 10 Sustainable Energy Harvesting Technologies: Past, Present and Future 4. Hybrid flexible energy harvesting and energy ... Circuits and Systems, vol.2, no .4, pp.251-259, 2008.168 Sustainable Energy Harvesting Technologies – Past, Present and Future 14 Sustainable Energy Harvesting Technologies: Past, Present and Future At ... from rest of the circuit,160 Sustainable Energy Harvesting Technologies – Past, Present and Future 2 Sustainable Energy Harvesting Technologies: Past, Present and Future μW. Indoor light intensity...