In order to meet the requirements of 2000 watts, you will need multiple solar panels which might stretch across the top of your roof.
Here's an example of a 2500 Watt solar panel set.
https://www.anapode.com/products/2500w_2_5kw_Complete_Solar_Panel_Module_Kit_DIY
Here's an example of the charging times of a big power pack(battery) made by Goal Zero.
http://www.goalzero.com/p/140/goal-zero-yeti-1250-solar-generator
If you scroll down to where it's written, "Charge Times" and the blue box highlighted is the one for the product being shown (Yeti 1250). Those Nomads with the #'s (that means number for those younger people, not hashtag) are the wattage from the solar panels, that Goal Zero provides.
Now this is not a set standard or anything like that at all, but I'm just trying to give an example -or tip of the iceberg- of what you might be getting into if you want to create a Solar Grow.
I've found a thread similar from a different forum.(I hope I'm not violating any rules by posting other forums).
http://www.rollitup.org/grow-room-design-setup/399377-solar-power-grow-room-can.html
If you check the 5th post down from the top, there's a person named Blazn. He has a little more information about a solar grow.
From the most part it seems like they are all very very expensive.
TL

R (Too Long

idn't Read)
It will cost more than an arm and a leg to have a solar powered grow, and it will require to gain more knowledge of how solar power works and the numbers that is needed for it to work.
I'm sorry for bursting your bubble and the long post. (>.<);; Here's a kitty for the long post and to cheer you up.