Hot water is the second largest energy consumer in American households. A typical 80 gallons (300 l) electric water heater serves a family of four consumes approximately 150 million BTUs in his 7 years of life. It costs about US $3,600 (US$ 0.08 per KWH), excluding fuel costs rising. It will then be replaced by another like him. Hmm. Perhaps we should rethink this...
Make an investment in a solar water heater is the stock market every day, each decade without risk. Initial return on investment on the order of 15 per cent tax exempt, and goes as a gas and electricity prices climbing. Many States have tax credits and other incentives to sweeten these figures still. What are we waiting to for? Forget the stock market. If you have invested in a House, you should be your next investment in solar hot water.
In this article, I will be the most commonly used options for the solar water heating, principles of operation, and some historical perspective on what works and what does not cover.
A Checkered Past, A Bright Future
Solar thermal past is a good example of why everyone should be skeptical State participation in energy. Lucrative federal tax credits for solar energy were begun under President Jimmy Carter in the 1970s, and suddenly eliminated under President Ronald Reagan in 1985. This deals with the solar industry of a devastating "one-two punch", from which it always has not yet recovered.
The intention was to stimulate sales for solar thermal systems. But an aggressive promotion of tax credits solar energy tax credits surrendered. The baby industry was overwhelmed, to meet the demand. The demand disappeared, were disposed of as tax credits, and a majority of solar thermal company went out of business. Thousands orphaned solar systems were left behind the search after a service technician.
The solar thermal industry experts has washed the tax credit telemarketing and overnight. Today's solar thermal industry includes reliable, efficient products and well seasoned professionals who have seen it all. Solar water heating is one of the best investments you can make for your home and the environment.
First Things First The best savings in hot water come from no cost or low cost options. Before you tackle solar hot water, take these steps:
Turn the thermostat down. Many water heaters are set to between 140 and 180°F (60 and 82°C). See how low you can go. Try 125°F (52°C) for starters. A hot tub is 106°F (41°C). How much hotter do you need?
Wrap the water heater with insulation. Insulated water heater "blankets" are usually available where water heaters are sold. (Be careful with natural gas or propane fired water tanks. They use an open flame to heat the water. You need to provide a space for air at the bottom of the tank, and at the top where the flue exits the tank. Safety comes before efficiency!)
Fix those drips. They may not look like much, but they are a constant and persistent drain on your water heating load, and they waste water too.
Use flow restrictors and faucet aerators to reduce your hot water consumption.
Find other ways to use less hot water. Wash only full loads of clothes and dishes.
Insulate your hot water pipes.
How Large a Solar Hot Water System Do You Need?
Hot water use in the United States is usually 15 to 30 gallons (55-110 l) per person per day for home use. These include above all bathing, washing and dishwashing. But your commitment to efficiency has much to do with your actual use.
Below: A 40 gallon batch heater.
The hot water tank is usually to be that to treat one day in consumption. So for a household with four, it would be useful daily water requirement of 20 gallons (75 l) per person a 80 gallons (300 l) tank, and day are based.
Smitty and Chuck at AAA solar in Albuquerque have based on your climate area use dimensioning according to generally accepted rules of thumb for solar thermal collectors:
In the Sunbelt, you use 1 square foot (0.09 m2) collector area per 2 gallons (7.6 l) fuel capacity (daily use in the household).
In the Southeast and mountain use States, 1 m2 collector area per 1.5 gallon (5.7 l) fuel tank capacity.
In the Midwest and Atlantic States, you use 1 m2 collector area per 1.0 gallon (3.8 l) fuel tank capacity.
In New England and the Northwest, you use 1 m2 collector area per 0.75 gallons (2.8 l) fuel tank capacity.
Based on these rules of thumb, a household with four with a 80 gallons (300 l) tank is required about 40 square meters (3.7 m2) of the collector in Arizona, 55 square meters (5.1 m2) of the collector in South Carolina, 80 square foot (7.4 m2) of the collector in Iowa, and 106 square metres (9.8 m2) of the collector in Vermont.
Of course, there are these great ballpark calculations that will be affected your incoming water temperature, hot water set point, the actual use and the intensity of solar resources in your site. You should generally assume that this will give you 100% of your hot water needs in the summer and about 40 percent of your hot water needs throughout the year.