I was surfing around on the City of Santa Rosa website and ran across this interesting information, Santa Rosa along with PG&E has set up a number of energy-efficient demonstrative street light fixtures (LED and Induction) to compare to the current high pressure sodium lights. It gives us all the opportunity to see these technologies in use next to each other, which is nice.
There are significant energy savings (more than 50%) for either LED or Induction when compared to high pressure sodium, but there are some higher inital product cost. There is more info on the city website, including the demostration intersection for those who are interested.
The LEDs have been installed throughout the country as an energy saving device. Personally, I like their intensity, making them easier to see, especially in inclement weather. I do find the “flashing” ones distracting (stop at the westbound intersection at Piner & Airway for an example when the green light initiates). I have read that LEDs do present a problem in colder climates… they do not develop the same heat as the old lamps, allowing snow and ice to accumulate and, eventually, obliterating the light from view. Hopefully, this problem will get resolved in an energy efficient manner as well.