Shouldn't the tags above be merged?
I think power-supply should be used when talking about powering the Raspberry Pi or its peripherals using the standard micro-USB charger.
While alternative-power should be used when not talking about the micro-USB charger. Such as solar, wind, or PoE.
I created the alternative-power tag since alternative energy is quite a large sector which the raspberry pi would be good for diving into at an experimental and hobbyist level.
When I realised not everyone agreed, I removed the tag (since it was only on one post) however I fully support bringing it back and believe it could be very interesting if people choose to use it.