Thanks for the figures.

There's another general issue with this in that I can position solar panels to be best for receiving light and the bulb best for projecting it. A glowing leaf needs to do both.

Perhaps there are other good uses, if this can be targeted to specific issues with a plant (e.g. make it happen when they're being attacked by bugs, or need watering, or something like that) then it could be used as a signal we can cheaply detect.