I use a purchased high power full spectrum (UV included) panel, from Amazon, for seedlings and cutting growth over winter. But my setup is very small. I've also tried a bunch of "daylight" LED light sticks, obtained from Habitat ReStore, in a tiered setup to maintain close distance. These did ok. You have to be super careful with cheap light sticks because they are often not moisture-safe (connected directly to the AC main without transformer or protective circuit). Grow lights sold at the home repair big box stores, were weak and just not worth it, but I've got one fixed on a citrus plant to supplement it.
A short while ago, Costco had a great deal on a three panel cob "garage light" of 8000 lumens, daylight color. Picked them up for $16 each. One lights up my SUV sized garage in a box, and another my garage. I'd definitely use a few of those as a start for a larger setup. I'm overwintering my Ashitaba plants in the SUV shed with one of those and they are looking very nice, if a bit deeper green - I don't think they are getting quite enough power due to the distance from the lamp, but they are producing new stalks, which is really remarkable to me. Twelve of those units would approximate the strength of a mixed sun and cloud day.
I have 2 sonlipo from Amazon and they are good so far, it's only been 2 years. They're not solar. I'd probably have to cover the greenhouse in solar panels just for a charge. I've also used t5 florescent but they give off a lot of heat.