... μW≈ 60 %.At 320 lux, G = 320/120≈ 2 .67 W/m2. 162 Sustainable Energy Harvesting Technologies – Past, Present and Future 10 Sustainable Energy Harvesting Technologies: Past, Present and Future 4. ... 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...