IKEA has been promoting compact fluorescent lightbulbs since 1997, when they sold over half a million CFLs at nominal cost. Not only did they manage to raise awareness of energy efficiency, they also managed to tackle the issue of mercury. Even today many CFLs contain mercury – IKEA took the bulbs back in-store for recycling, avoiding landfills and incinerators.

The IAEEL estimated the impact of that campaign to 35 GWh of reduced energy demand – equivalent to over 6 million tonnes of CO2 (using 0.19 kg/KWh for natural gas, 15 million tonnes for coal at 0.43 kg/KWh). To me the biggest impact was increasing competition at a critical time, and making these bulbs mainstream.

Links:

http://www.worldchanging.com/archives/006278.html

http://www.iaeel.org/IAEEL/newsl/1997/tre1997/LiMa_c_3_97.html