Ouch! Ditch one of the lights and get a different bulb or you'll burn your plants. You want maybe a 6500K or 5000K. You could maybe mix one 10,000K bulb and something like an HPS bulb (if your lamp supports that) to get a more natural daylight colour, but I think that 500W is going to fry your orchids and even 250W might be too much for some species. Watch out for heat buildup, you'll probably need a fan.

id get some compact flouros.they work great and use less electricity too.

Less electricity = less light. Pick a bulb that gives you the amount of light you need, and preferably pick an efficient one, so that you don't use more electricity than you need to.