The Case Against Halogen
A 50W halogen downlight converts about 90% of its energy into heat and 10% into light. That heat accumulates in ceiling spaces and poses a fire risk, particularly where insulation is compressed around or over the fitting. Each 50W halogen fitting costs roughly $65–$90 per year in electricity to run at 4 hours per day.
A home in Rutherford or East Maitland with 15 halogen downlights is spending $975–$1,350 per year just on those lights — more if they're on longer. The ceiling heat accumulation in summer also increases air conditioning load.