I put up a whole thread on just this topic. See here for much more discussion:
https://www.rollitup.org/led-other-lighting/489381-cheapo-14-watt-225-diode-2.html
Consensus seems to be that these are worthless for actually growing cannabis, but might be OK for sprouting seedlings or maintaining clones. I think something like this would probably work well for maintaining a houseplant that doesn't really need intense sunlight, and that's really all these small panels are intended for, anyway.
Comparing these low-end 13-14 watt panels to incandescent bulbs doesn't make sense, since incandescent bulbs put out a relatively poor light spectrum that isn't useful for growing plants.
As a very rough rule of thumb, you can figure a high quality (that's key) LED can put out light equivalent to 2 - 2.5x its wattage in HPS lighting, or maybe 3x its wattage in fluorescent.
So a good 13 watt LED might work as well as say 25-30 watts of HPS, or maybe 35 watts of fluorescent. In other words, at best a small LED panel like this might be adequate to light one really tiny plant.
Realistically, though the spectrum put out by one of these cheap panels probably isn't nearly as good as an HPS or even a CFL, and you're probably not really going to see 2-3x the per-watt efficacy. An ordinary $5 26 watt CFL with a good reflector will probably do as well as this LED panel.