The home factor was the highest in my carbon footprint, and though that was mostly due to the lights in my house, I know that some of that was due to water heating. I like to take to take hot showers, and they tend to be on the longer side. Besides taking shorter showers, another way to reduce the energy used to heat the water used in my showers is to use solar water heaters.
Solar water heaters use sun as their fuel, so they are energy-saving as well as cost-efficient. Sunlight is used to heat water that is then supplied to the house by a pump. Solar water heaters are a great idea for those, like me, who like long, hot showers!