Published by Green by Design under Renewable Energy

One of the most overlooked and forsaken appliances is the the hot water heater. How many of us pay any attention to it until the hot water runs out in the morning shower? It should be on our immediate list of appliances for an upgrade to a greener alternative.

You should start by visiting your storage or utility closet and see if you are hiding a large round 40 to 60 gallon water tank. That water in your closet is being heated when you are sleeping, at work or on a vacation. Not a great way to save on those rising energy bills.

For the “green home” the tankless hot water systems make the most sense. They are “on demand heating” so water is heated only when you need it in real-time.

They come in two common forms: gas and electric. The gas tankless water heaters are most commonly used for whole house applications and are normally more powerful, but come with more requirements than electric. Electric models are best used for single point or point-of-use. Examples would include a bathroom or kitchen sink.

Savings range from 15% to 50% over a conventional hot water tank and can be further increased by adding solar thermal to have the ultimate green hot water solution.

Even though design does not really factor into the buying choice, Rinnai (image left) and Stiebel Eltron (image above) have come out with some attractive gray/silver box covers…though there is nothing bad to say about the plain white box. What I would look for is the required heating capacity of the water you will use and then compare price. Prices start as low as $200 for a point-of-use electric, then $400 for smaller homes and over $1200 for the medium and larger homes. Each manufacturer has several models to choose from. As an example Bosch tankless water heaters include AquaStar 2400E ($1240), the most energy efficient in the Bosch line, or the 1600PS ($750), specifically designed as a backup to preheated water produced by solar-based systems or from woodstoves.

Note: Though many do-it-yourself homeowners are able to install them, it is recommended to use a professional.