Cannabis needs lots of light.
The best option currently are still HPS lamps. They produce lots of light per electricity used. They are also inexpensive to buy.
On the downside HPS (High pressure Sodium) lamps produce lots of heat and use lots of electricity.
Alternatively, you could use LED grow lights. Quality ones will work just as well but are much more expensive to buy.
And, if you want to grow on a very small scale you could use CFL lamps. 1 x 150 Watt CFL will work for 1-3 plants.
I recommend you use HPS as its still the best all-round solution. These lights come with a ballast to run the bulb.