LED lights are more expensive to buy, but if you include the costs for maintenance (replacing light sources) and operation (energy consumption) and compare this to conventional light sources, investing in LED lights pays for itself pretty quickly.
Compared to mains voltage halogen, the investment pays for itself in just a few years in the average house, and after that you continue to save money during the years they remain in service.
LED lighting can cut energy consumption by up to 85% compared to incandescent light sources and by 50% compared to low energy lamps (compact fluorescent lights), all while lasting 4–40 times longer.