No, I don't think so--they are only 18W and they are the incorrect spectrum. You are going to want higher wattage lights and something in the 6500K range for vegging. If you use them for flowering also, you need tubes in the 2500-3000K range.
The tubes that are thicker are not T5s. The number after the T denotes the size of the tube in 1/8s of an inch--i.e. T5s are 5/8" in diameter, T8s are 8/8 or 1", T12s are 12/8 or 1-1/2". The T5 has substantially more lumens per watt than either of the other 2 types of bulbs, which is what makes the T8s and T12s not a good choice. The T5s will put out as much or more lumens per watt as MH lighting. But as mentioned, the spectrum is also important. Something in the 4100K range is made for people, not plants.