How to Help Your Water Heater Save You Money | eHow.com. Almost everyone has a water heater. If you want to save money on your energy bill, starting with your water heater is a great place to begin. Simply replacing your 10 year old water heater with a new one will save you on energy cost as new water heaters have become very efficient over the past 10 years. Here are other tips to consider which will also help you save on energy costs.