written by Greg Shaw, Solar Energy Consultant and Managing Director, Hua Hin Solar Co., Ltd. Question: How many years will it take for my 5KW or 10KW system pay itself off? Answer: Explained in an honest manner in a recent email response to one of our customers. Dear [valued customer], Thank you for asking about two scenarios: best case and pessimistic case payback periods for your solar system. We will do our very best to give you a proper…