Years ago when my natural gas water heater broke I looked at various options. Solar wasn't feasible due to the orientation of my roof, and operational costs were the same with oil, so rather than pay to change over the piping I stayed with what I had and I regret it. Natural gas is provided by a monopoly utility that is constantly raising prices whereas oil is a competitive marketplace with many local dealers and prices have fallen over the years. Electric by the same utility is exorbitant and the worst way to go in my area.