Do you live in San Mateo County? Peninsula Clean Energy (PCE) has big rebates for replacing your water heater!
 
You could be eligible for $2,500 or more if you replace your methane gas water heater with an electric heat pump water heater. Why switch? Heat pump water heaters are cleaner and safer than gas water heaters.
 
If you are a CARE/FERA customer, or if you are upgrading your electrical panel, you could be eligible for even bigger rebates.