Does anyone have any information on plasma streetlights? Whatever happened to them? Were any installed on a large-scale basis?  I think they first showed up in the early 2010s if I'm not mistaken.

There were some disputes about these lights jamming Sirius satellite radio service.
Because morons at Sirius thought it is very wise strategy to save money by using "free" ISM 2.45GHz band instead of proper licensing of some brequencies when designing a system involving billion dollar investment into satellite fleet. And then later, when someone really uses the band for its original purpose (aka microwave energy transfer, with some inevitable leaks outside), Sirius starts complaining those lights must be made so they would not disturb their radio service. And moron courts sided with the radio, completely ignoring what the band primary allocation was in the first place.

Wow, never heard of them, that's super cool!

Here are some things that may be of interest,

https://www.forbes.com/sites/kerryadolan/2010/09/01/beyond-leds-indiana-town-goes-for-light-emitting-plasma-to-save-money/

https://www.researchgate.net/publication/330347309_Cost-and_Energy-Effi_cient_LED_Induction_and_Plasma_Roadway_Lighting_JOINT_TRANSPORTATION_RESEARCH_PROGRAM

https://www.google.com/maps/@38.6866421,-85.7703508,3a,15y,139.46h,112.45t/data=!3m8!1e1!3m6!1sy5SbFd9FtiK0sr2O0WvZ3w!2e0!5s20230601T000000!6shttps:%2F%2Fstreetviewpixels-pa.googleapis.com%2Fv1%2Fthumbnail%3Fcb_client%3Dmaps_sv.tactile%26w%3D900%26h%3D600%26pitch%3D-22.446525305680254%26panoid%3Dy5SbFd9FtiK0sr2O0WvZ3w%26yaw%3D139.46317349208232!7i16384!8i8192?entry=ttu&g_ep=EgoyMDI2MDMxNS4wIKXMDSoASAFQAw%3D%3D

One company who made these streetlights appeared to be called Luxim, who seemed to be at the wab address of http://Luxim.com , they seemed to be out of buisness by 2015. Unfortunatley the wayback machine isn't working for me right now, so I can't see what's in that site.

Hope this stuff helps.

There is quite detailed Youtube teardown video from Australia on dismantling sulfur microwave lantern.

As much as we all love conspiracy theories, I believe the system was buried by pure economical reasons:

- tremendously overcomplicated! Really visible in this video. Incessant RF shields to keep microwave energy at home. Two running fans to keep the thermal mode - imagine this in an outdoor lantern!!! An extra motor just to rotate discharge bulb.

- huge bulky expensive and inefficient transformer to power magnetron

- magnetron is inefficient by iself

- magnetron has a finite life of just a few thousand hours

...And moron courts sided with the radio, completely ignoring what the band primary allocation was in the first place.

That's not actually true, they sided with the lamp manufacturers. From Wikipedia: "In May 2003, the FCC terminated the proceeding that would have defined out-of-band emission limits for radio-frequency lights operating at 2.45 GHz, saying the record of the proceeding had become outdated and Fusion Lighting had stopped working on such lamps.[9] The order concluded:

We therefore decline to provide the requested relief from the Satellite Radio Licensees to prohibit operation of all RF lights in the 2.45 GHz band, as we find that the requested prohibition is overarching and is not warranted based on the circumstances. If there is evidence that any entity will seek to operate RF lights in the 2.45 GHz band and cause harmful interference to satellite radio receivers as a consequence, and our existing limits prove inadequate, we will at that time take appropriate action."
- https://en.wikipedia.org/wiki/Sulfur_lamp#Electromagnetic_interference