Making recessed cans more energy efficient
Attempts to improve the energy efficiency and air leakage in recessed down lights have been difficult. One solution has been to install airtight fixtures into insulated areas (i.e., everywhere in a single-story house or on the top floor of a multi-story house) which will help avoid the leakage of air into unconditioned space. Moreover, it is stated in 67% of building energy codes that airtight fixtures are required in all insulated ceilings.
A way to improve lighting energy efficiency is through the use of compact florescent lamps (CFLs) instead of incandescent bulbs. By replacing incandescent lamps with screw-in CFLs lighting energy will be saved immediately but the light from a CFL will dissipate into the recessed fixture decreasing the effectiveness of the light. A solution to this problem would be to use reflector lamps. Unfortunately, there is not an amply supply of CFL reflector lamps currently available in the consumer market. Furthermore, the higher wattage of the screw-in CFLs bulbs generate a larger amount of heat inside the airtight recessed can. This high heat can decrease the life span of the CFLs and result in a lower light output.
This technical problem has proven to be difficult to solve due to the necessity of creating recessed fixture that meets numerous requirements yet it still affordable for the consumer market. They fixture must be airtight, rated for use in insulated ceilings and designed specifically for use with pin-based (not screw-in) CFLs.