... Calculated based upon 8 hrs/day, a N series Bulb can last over 9 years.Easy to ... bulbItemsTraditional bulbCGX LED bulbLight sourceIncandescent bulbQTYLED CGX B series LED bulbQTY44w2,000pcs7.5w2,000pcsMaintenance fee1-year lifespan, ... 200 kWh /9 yearsElectricity fee$46,252.80 / year$7,884.00 / year$416,275.20 / 9 years ... years, totally 2,000pcs of CGX 6w B series LED bulb can save $345,319.20 electricity ...