Another driving factor is saving maintenance costs in applications such as street lighting, where man hours and equipment needs could cost hundreds of dollars just to change out a blown bulb. With the much longer life of LED based lighting systems, much of these maintenance costs can be measurably reduced. Also, it is just a matter of time when the light engine of an LED based system is in the price range of a CFL lamp. As adoption increases, the economies of scale will start producing significant downward price pressure, improving the cost of ownership. Finally, LEDs are advancing in both efficiency and cost. They work exceptionally well in cold weather and lend themselves to easy control. In the future, adaptive lighting will be the norm, not just for esthetics but as a strategy for energy savings.