# are they solar panels? **URL:** \ **Category:** Factual Questions\ **Created:** [May 2, 2003, 3:00pm UTC](https://boards.straightdope.com/t/are-they-solar-panels/172635 "2003-05-02T15:00:47Z")\ **Posts on this page:** 8\ **Page:** 1
**Author:** ![idol\_mind](https://avatars.discourse-cdn.com/v4/letter/i/94ad74/32.png) [@idol\_mind](https://boards.straightdope.com/u/idol_mind)\ **Post date:** [May 2, 2003, 3:00pm UTC](https://boards.straightdope.com/t/are-they-solar-panels/172635/1 "2003-05-02T15:00:47Z")
okay, this is a question that has stumped my friends and i ever since we noticed these things on the side of highways (possibly the sides of roads somewhere but we’ve only noticed them on highways)…they basukly look like solar panels. they’re stuck in the ground and on a pole probably 5 to 8 feet tall. there aren’t any wires going from them to somewhere else that we can see (if its connected to something else the wires are underground) i first noticed them on my way to work one day and started asking people but nobody had any idea what i was talking about…so i started showing people what i was talking about and they had no idea what they were for can someone PLEASE help me figure these things out i’m pretty sure they’re solar panels, but what are they for? ---
**Author:** ![friedo](https://avatars.discourse-cdn.com/v4/letter/f/8edcca/32.png) [@friedo](https://boards.straightdope.com/u/friedo)\ **Post date:** [May 2, 2003, 3:05pm UTC](https://boards.straightdope.com/t/are-they-solar-panels/172635/2 "2003-05-02T15:05:08Z")
Are they near street lights? A given section of street lights are usually connected to a small solar panel which closes a relay circuit to turn the lights on when it gets dark. ---
**Author:** ![Mangetout](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mangetout/32/19_2.png) [@Mangetout](https://boards.straightdope.com/u/Mangetout)\ **Post date:** [May 2, 2003, 3:07pm UTC](https://boards.straightdope.com/t/are-they-solar-panels/172635/3 "2003-05-02T15:07:13Z")
I’ve seen roadside equipment (weather monitoring/traffic counting stuff) that is solar powered; a grey box with a tall pole\*, then an angled solar panel and often some radio antennae. I suppose it makes sense, rather than having to run power to the thing or change batteries periodically). I assume the tall pole is just to keep the panels out of reach of vandals. ---
**Author:** ![idol\_mind](https://avatars.discourse-cdn.com/v4/letter/i/94ad74/32.png) [@idol\_mind](https://boards.straightdope.com/u/idol_mind)\ **Post date:** [May 2, 2003, 3:10pm UTC](https://boards.straightdope.com/t/are-they-solar-panels/172635/4 "2003-05-02T15:10:01Z")
that could be it, but i’ve only notice 1 of them on this highway by my house, and there are lights all along the highway, but if this were the case wouldn’t they be on all highways, and wouldn’t it take more than one to power a stretch of highway?..maybe i’m just not noticing exactly how many are out there ---
**Author:** ![Mangetout](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mangetout/32/19_2.png) [@Mangetout](https://boards.straightdope.com/u/Mangetout)\ **Post date:** [May 2, 2003, 3:10pm UTC](https://boards.straightdope.com/t/are-they-solar-panels/172635/5 "2003-05-02T15:10:28Z")
Like [this](http://www.sunlightsolar.com.au/Solar%20power%20Systems.htm) ---
**Author:** ![idol\_mind](https://avatars.discourse-cdn.com/v4/letter/i/94ad74/32.png) [@idol\_mind](https://boards.straightdope.com/u/idol_mind)\ **Post date:** [May 2, 2003, 3:14pm UTC](https://boards.straightdope.com/t/are-they-solar-panels/172635/6 "2003-05-02T15:14:33Z")
yes that is very very similar to what i’m seeing, thanx, now i can go tell my friends i’ve figured it out ---
**Author:** ![friedo](https://avatars.discourse-cdn.com/v4/letter/f/8edcca/32.png) [@friedo](https://boards.straightdope.com/u/friedo)\ **Post date:** [May 2, 2003, 3:14pm UTC](https://boards.straightdope.com/t/are-they-solar-panels/172635/7 "2003-05-02T15:14:52Z")
> [@](#): > > \*Originally posted by idol mind \* > that could be it, but i’ve only notice 1 of them on this highway by my house, and there are lights all along the highway, but if this were the case wouldn’t they be on all highways, and wouldn’t it take more than one to power a stretch of highway?..maybe i’m just not noticing exactly how many are out there The solar panels don’t power the lights, they just control the switch that turns them on and off. Their only purpose is to sense when it gets dark. So a single panel may control many hundreds or thousands of individual lights for many miles. They could also be weather stations as **Mangetout** points out. ---
**Author:** ![idol\_mind](https://avatars.discourse-cdn.com/v4/letter/i/94ad74/32.png) [@idol\_mind](https://boards.straightdope.com/u/idol_mind)\ **Post date:** [May 2, 2003, 3:16pm UTC](https://boards.straightdope.com/t/are-they-solar-panels/172635/8 "2003-05-02T15:16:51Z")
ohhh