Guide to hot water heaters
Traditionally, hot water heaters provide hot water by heating cold water and storing it in a tank for later use. This means that you can use only as much hot water at a time as your tank can hold, more or less, and that it is advisable to avoid overusing hot water so you don't run out of it just when you need it most. However, water heaters that don't need a storage tank are becoming more popular.
There are four main types of water heaters used in contemporary homes. Each type uses different technology to supply the household with warm or hot water on demand.
The Four Main Types of Water Heaters
Storage tank water heaters are extremely common. Electric water heaters employ storage tanks to hold hot water until it's needed, as do oil and gas water heaters.
As an alternative, tankless water heaters are available. These are usually installed near the point of use only, as they are not designed to meet the hot water needs of an entire house, but rather just a single part of it. Normally, they are used in supplemental applications, though they are becoming more popular as emerging technologies such as the low-mass water heater are able to efficiently deliver much higher volumes of hot water than a traditional tankless system.
Third, integrated systems are available which create hot water both for human use and for space heating. Certain types of furnaces, including those which use radiant heat distribution methods, rely on hot water to heat the house. Integrated systems help you save money by using a single means to generate hot water for cooking, bathing and space heating.
Finally, solar water heaters are the choice of many ecologically conscious homeowners. Rather than relying solely on electricity or fossil fuels to heat water, solar water heaters draw on the sun's energy to supplement the process. The most efficient solar water heaters are able to draw 50 percent of their power from the sun.
Heat pump water heaters, though less common than the four major types, are also extremely efficient at warming water and are favorably viewed by most consumption-conscious homeowners.
To find the water heater that's right for you, sit down and crunch some numbers. Look at the costs to buy, install and run each option. Higher purchase and installation prices are often offset by lower operational costs. The only way to know for sure which will be most cost-effective option for you is to track your hot water consumption and do the math.