Changing from 18h of light to 24h?

Hello. Originally, I started with 18h of light to keep my electricity bill down. I read an article, and it said that plants under 24h will grow faster than plants under 18 hours of light. Can I switch to 24 hours of light? Will it effect the plants? Thanks.

well i run mine during veg at 24/0 , but i use fluorescence bulbs. intensity of lights/heat are not an issue for me.
depends on your environment/intensity of lights ... if you are running HID and find your temps getting too hot for them... than 24 hrs is probably not the best.

yes you can switch to 24 hours no problem... Just make sure temps don't get to warm in the hottest part of the day..

CFL's will keep your bills right down and will deal with any heat issues you might course by switching to 24/0. They are also cheep to buy and easy to get your hands on. What lights are you using and how's the ventilation on your grow room?