Question 1: Which solar panels are you using? Blutricity ones via Redpower, or the IC2 ones.
Question 2: Are you using Redpower solar panels with IC2 circuitry (that won't work)
Assuming we're talking straight IC2, do you have the following:
1. Unobstructed daylight
2. Either:
a. Batteries in your solar panel(s)
b. Wires leading from your solar flower to a batbox, MFE, or MFS?
3. Are you using long copper wire? If so, you might be experiencing severe energy degradation. This can be solved by moving your storage closer to the flower, or using glass fiber cables (expensive to make).
Also, Technic has been updated to Technic 6 (for some time now), so good luck using backdated crap.