well these only being 13w you can do all them on 1 cord im its got to handle it but you can put them all on one cord. im only using 5 of mine. thats only like 65 watts a normal house bulbs only 60w maybe 100w.so if your using these bulb you could be safe long as the cord can handle the load.also if you use like anything over like 20watts i wouldnt put any more then like 60watts worth of cfl's on a plug.
Thanks stoney_stoner, Yeah I was just going to put them on one cord. I got a mh. 175w that I'm just going to run to the breaker. And then run another wire for a pugin for the fans and stuff. I think it will be fine. I have to look at the breaker and see how me amps it is. I 15 amps breaker would would work fine with it.