Here’s two easy ideas to help save you money and the planet. Adjust your water heater. If you lower the thermostat on your hot-water heater from about 145 to 120 degrees, the change isn’t likely to be noticeable. This step could save you more than $20 a year if you heat water with gas and more than $50 if your water heater is electric. Buy a programmable thermostat for your home. They cost between $30 and $100, but that’s money you’re sure to make back over the course of a year because your energy bills will drop. A programmable thermostat allows you to adjust your home’s temperature on a predetermined schedule, so you don’t unnecessarily waste energy when you’re not home or when you’re sleeping.