Frequently Asked Questions About Solar Energy

What is a solar water heater ?
A solar water heater uses the sun’s energy to pre-heat household water before it enters the conventional gas (or electric) water heater. In areas where an abundance of sunshine exists year round, a solar water heater can generate up to 90% of your annual water heating needs.
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How hot can solar heated domestic water get?
Water heated by the sun can reach temperatures exceeding 212º F, but the normal temperature for household use is only 120º to 130º F.
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Are there different kinds of solar water heaters?
Solar water heaters are divided into two kinds of systems: active and passive. Active solar systems, like the drainback systems, rely upon moving mechanical parts in order to transport heat, while passive systems, like the Ezinc Thermosiphon, simply use the sun to accomplish this action. Most of the systems installed worldwide are passive because they are simple and need no auxiliary power (electricity) to operate.
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How do active solar systems like the drainbacks work?
The collector is usually an all copper tube and fin absorber enclosed with an insulated aluminum frame or “box”, covered with a low-iron tempered glass glazing. The water contained within the gas or electric water heater is circulated through the solar panels in a single-tank system, or a separate tank is used to pre-heat the water before it enters the conventional water heater in a two-tank system. A two tank system is usually considered to be the best option but if properly managed, a single tank system can provide between 50 and 80% of the household needs for hot water. The water being circulated is gradually heated and the system should be sized to provide between fifteen to twenty-five gallons of hot water per person per day. A reliable automatic control to operate the pump is essential. Fortunately, pumps and electronic controls have evolved and can be expected to provide over twenty years (and counting!) of service.
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How do passive solar systems like the Ezinc Thermosiphon work?
Passive solar systems are popular because of their inherent simplicity and reliability. The storage tank is located on the roof and the heating effect of the sun causes warm water to circulate within it. Cold water from the city flows directly to the tank on the roof, and then flows to a conventional water heater located on the ground level. It is desirable to keep the distance between the solar system and ground level water heater as short as possible in order to reduce the amount of cold water sitting in the pipe between the two units. In a thermosiphon system, an insulated tank will prevent the loss of stored heat during the night.
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Will solar heating affect how much water I will have? Will I have to change my bathing and cleaning routine?
Yes and No. You will actually have much more hot water than ever before. If the system is sized well for your family, you will no longer need to wait for the water heater to ‘recharge’ between showers.

Solar water heaters are always installed in addition to your regular water heater. That means that even during bad weather you will still have hot water. To maximize your savings, you should attempt to use the most hot water in the late morning and early afternoon when the solar system is operating at its peak. Also, it helps to spread your cleaning load over the week. For example, instead of washing seven laundry loads all at once it would pay to do one a day. This will reduce the amount your regular water heater must operate.
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Will the solar system affect my existing water heater?
Yes. Since the water heater will operate far less frequently, solar will extend its life significantly. Some water heaters that were retrofitted with solar in 1974 are still in service today, over a quarter of a century later. The life of an ordinary gas heater without solar is between five and ten years.
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How much does a solar water heater cost?
The cost may vary from $4,000 to $6,000. It depends largely upon the following variables:

  • Size of the family to be served (and therefore the amount of heat required)
  • Size, type and brand of solar system
  • Type of roof upon which the panels are mounted
  • Building code requirements
  • Local incentives
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How much will I save?
It depends upon the size of the system and the needs of your family and the way you currently heat your water. The average annual cost for water heating is usually over half the annual gas bill. Typically a person uses between fifteen and twenty-five gallons of hot water a day, which can cost $5.00 to $25.00 per person every month. A family of four could be spending between $384 to $1200 a year just for heating water. A gas bill is charged at varying rates or tiers, and the most costly level or tier is levied in winter, when you are using the most gas. A solar system can reduce your daily gas consumption and thus you will be purchasing the less expensive Tier 1 or “Lifeline” rates. If you are using an electric water heater your savings are even more as electricity prices are much higher than gas.
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Are there any public incentives available to reduce the cost of a solar water heater?
Yes. There is a federal tax credit available to help lower the final cost. It is 30% of the cost with a maximum limit of $2,000. If the water heating system is used in a business then there is no limit or cap and accelerated depreciation (MACRS) can also be used to reduce the financial impact. In addition to that, state and local utility companies also can have incentives. For example, the city of Tallahassee pays up to $900 for a solar water heater. The best website to check for local rebates is
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How long does it take for a solar heater to pay for itself?
Solar heating does have a payback, and it can vary from 4 to 6 years. But it may be more useful to think of solar as an investment that yields an annual return, much as a bank savings account provides interest. A solar water heater will generate savings that can equal a bank account generating a twenty percent (20%) annual return, and the savings are not taxed as income, as is the interest you earn at the bank. The truth is, if you want hot water… you will be paying for that heat. You may prefer to pay the utility bill forever, or you may wish instead to go solar, and become your own utility. It is quite similar to the reason you once decided to buy your home and stop renting. Solar is simply the best investment available today because it guarantees a return on money that you will otherwise “burn” and helps you develop equity as you bank your savings.
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Can my Homeowner Association prevent me from installing solar equipment on my home?
Florida law forbids ordinances, deed restrictions, covenants, or similar binding agreements from prohibiting solar equipment use. Under this law, a homeowner may not be denied permission from an HOA or similar entity to install a solar collector or other solar energy device. Your HOA does not have the right to prevent you from installing solar panels on your roof. Other states have similar laws. For more information on the Florida Statutes, visit these links: Florida Solar Rights Law & 2010 Florida Statute 163.04.
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