Solar Hot Water Systems

Solar hot water systems work well in many different Climates and are extremely cost effective to run. Solar water heating has existed for centuries and has been used for bathing, hand washing, and home heating. It has always been a very effective method to heat water, but modern materials and knowledge have made the process far more efficient.

A solar water heating system is a rewarding investment. It can reduce your quarterly water heating bill while helping to protect our environment. Being informed and planning carefully will ensure that you’ve chosen the right system for you and your family.

What is solar heating?

Solar heaters, or solar thermal systems, provide environmentally friendly heat for household water and swimming pools. The systems collect the sun’s energy to heat air or a fluid. The air or fluid then transfers solar heat directly or indirectly to your homes water, or pool.

Solar water heaters, sometimes called solar domestic hot-water systems, are a good investment for you and your family. Solar water heaters are cost effective for many applications over the life of the system. Although solar water heaters cost more initially than conventional water heaters, the fuel they use—sunshine—is free.

Solar heating technologies can be used in any climate. To take advantage of solar energy, you usually need to have an unshaded area that faces north, northeast, east, west or northwest, such as a roof. The type of system you choose, including the type of collector depends on several factors. These include your site, your household requirements, the climate you live in and site specific installation considerations.

What are the basic components of a solar thermal system?

Solar water heaters are made up of solar collectors, and all systems except pool heaters have some kind of storage. In pool systems, the swimming pool itself is the storage, and the pool’s filtration pump circulates the pool water through the collectors.

There are different types of solar collectors available, they are flat-plate and evacuated-tube collectors. Flat-plate collectors are the most common type. Glazed flat-plate collectors essentially are insulated, weatherproofed boxes that contain a dark absorber plate under one or more glass covers. Unglazed flat-plate collectors are simply a dark absorber plate, made of metal or polymer, without a cover or enclosure. Unglazed flat-plate collectors made from polymer materials are typically used in solar pool-heating systems.

Evacuated-tube solar collectors are usually made of parallel rows of transparent glass tubes. Each tube contains a glass outer tube and metal absorber tube attached to a fin. The fin is covered with a coating that absorbs solar energy which inhibits radiative heat loss. Air is removed, or evacuated, from the space between the glass tubes and alows the metal tubes to form a vacuum, which eliminates conductive and convective heat loss.

Most solar water heaters require a well-insulated storage tank. Solar storage tanks include a conventional water heater and have an additional outlet and inlet connected to and from the collector.

Solar water heaters usually have a controller unit and may use small pumps to circulate water or glycol an anti-freezing heat-transfer fluid to and from storage tanks to the collectors. SolarGreen chooses to use extra pumps to circulate the water in cooler climates rather than an anti-freeze that could pose possible side effects if it were to leak.

Why should I invest in a solar thermal system?

The first question many people ask when considering a home expense is, “How much will it cost?” The answer depends on the quality and performance of the system, how you want to use it (water or pool heating, for example), and your geographic location.

Solar thermal systems usually cost more than a conventional gas or electric system (electric systems are being phased out in Australia). Today’s solar heating systems are cost competitive when you consider your total energy costs over the entire life of the system. Your gas or electricity bills will usually be lower and more predictable for as long as you own the house. You may even find that you have no ongoing electricity costs - this depends on the quality, installation, system performance and how you use your system.

Also, solar heating systems will insulate you from rising fossil fuel costs and protect you from gas fuel-price inflation over time let alone impacts from the new carbon tax. Investing in a solar thermal system could also increase the resale value of your home and increase the green rating required by the Federal Government before listing your home for sale.

Often, the entire initial cost of the system can be recovered when you sell your property. In addition, you will be earning an annual 6% to 25% tax-free rate-of-return on your investment, depending on how much hot water you use and how much energy you save.

Another important reason to invest in solar systems may be less tangible. When you purchase a solar heating system, you support technologies that are good for the environment. You are making a conscious, responsible decision to help reduce harmful emissions from fossil fuels, while maintaining your quality of life.