I have the same problem, and am a bit disheartened at the limited amount of mid-tier energy that can feasibly sustain a Matter Fabricator.
The easiest alternative, which I've come to embrace, is geothermal energy.
I play on the Ultimate Pack, so eventually I plan on having lava lake ages to support my lava needs, and that will pump through an endertank to my generators in the overworld. An endertank works the same way as an enderchest, but with liquids, from what I understand. After I've got 10-15 geothermal generators, I'm going to upgrade them into thermal generators, and then use that to power a matter fabricator. From there, I'll simply stock up on UU matter while I start compiling the other necessary materials to make the hybrid panels.
I like the fact that the made solar power endgame, but they may as well just remove the first two tiers of panels. They're virtually worthless, as by the time you have the silicon plates/UU matter necessary to craft them, your energy needs far outweigh what they can produce.