Are you allowing for cooling towers, water treatment, pipework, and so on? Also the grid connection hardware, spare turbines, cooling pumps, etc., and O&M costs?
$15/MWh is 1.5 ¢/KWh, right? that's pretty darn cheap and means that the other 10~20 cents would be transmission and fuel, yes?
20 cents? I pay 13/kWh.
You're within the stated range, do you think you have the most expensive electricity in the world? 25c/kwh isn't unreasonable. Ireland pays 52c/kwh.