It's very simple. Just figure out how many watts your fluorescent bulb is rated for. Figure out how many watts your combined string of leds are rated for. The led's will be much, much less. In each case, divide your watts by 1000, multiply the watts times the number of hours you plan to have them turned on, and multiply by your utility rate. This will give you a dollar to dollar comparison of each.
utility cost = watts/1000 x number of hours x utility rate
LED uses less, but if you'd like an exact answer -
There's a new product called Kill-A-Watt where you plug the device into the wall, then plug in one electrical device at a time. It will tell you exactly how much you're using. You can go around plugging in your computer, fridge, etc and know where all the money is going.
References :
It's very simple. Just figure out how many watts your fluorescent bulb is rated for. Figure out how many watts your combined string of leds are rated for. The led's will be much, much less. In each case, divide your watts by 1000, multiply the watts times the number of hours you plan to have them turned on, and multiply by your utility rate. This will give you a dollar to dollar comparison of each.
utility cost = watts/1000 x number of hours x utility rate
References :