What lighting are you thinking of getting? Marine tanks make quite a dent in the powerbill, and most of this is caused by metal halide lights and chillers. Metal halides are also really hot, which is usually why a chiller is needed. I think you should go with LEDs. They use less power, provide heaps of light, and don't need to be replaced for ages. There are a few really good modular systems out there. From what I have read, the EcoTech Radion and Aqua Illumination Sol Blue look to be about the best ones out there. If I was starting a marine tank I would go with the AI Sol Blue because it is cheaper than the Radion, and you can use it to its full potential with the AI controller, whereas the Radion needs to be plugged into a computer and you need to download software for it, so in my opinion the Radion is best for serious reef junkys who are obsessed with all the technical stuff. Although I have never kept marines, I do a lot of reading on the internet about it because I would really love to keep reef aquariums one day
HTH