My neighborhood in Washington, DC replaced its sodium streetlights with LEDs along its commercial corridor a few years ago. The replacements were going to be 40

My neighborhood in Washington, DC replaced its sodium streetlights with LEDs along its commercial corridor a few years ago. The replacements were going to be 4000K—not great for blue light. Luckily I was able to convince the city to source 3000K ballasts instead, which were just coming out on the market. They’re definitely “whiter” than sodium bulbs but 3000K has very little blue light and should be fine for melatonin. The number of streetlights was doubled, but power consumption was still halved; the LEDs paid for themselves. Finally, light pollution was reduced because the ballasts point down at a 45 degree angle. All of which is to say: with a bit of thinking and/or use of smart standards, it should be possible to use LEDs in streetlights to save energy, money, and reduce light pollution.