The graphs below outline the Cumulated Energy Demand and the Global Warming Potential (GWP) of the use phase in comparison with manufacturing phase. For the calculation of the CO2 emissions resulting from the use phase, an electricity mix causing 0.55 kg CO2 emissions per kWhEl was taken as a basis. Of course electricity production during use is also responsible for other environmental impact categories, but this depends very much on where the lamp is used. For this reason we have only depicted the CO2 impact, which may also vary depending on the location of use.
Equally depending on the electricity mix, a compact fluorescent lamp may also be responsible for mercury emissions during use. This is due to the comparatively high ratio of coal power plants in some electricity mixes, which emit mercury by burning lignite or hard coal to produce electricity. Nevertheless, in comparison to incandescent and halogen lamps, compact fluorescent lamps are associated with far less mercury emissions during use. This is due to their energy efficiency which is responsible for saving up to 80 percent of electricity and thus for reducing mercury emissions resulting from electricity production by coal power plants. In many regions of the world, the amount of mercury 'saved' is higher than the amount contained in a compact fluorescent lamp.
