If you are concerned about saving money on hot water heating costs, a solar hot water system may be the right choice for you. This system is a cost-effective way to heat water for household use and can be utilized in any climate. The energy source that is needed to power a solar hot water system is completely free, it comes from the sun.

How Does a Solar Hot Water System Work?

Solar hot water systems feature a solar collector system and storage tanks. The system can be active, meaning that there are pumps which circulate the hot water, or passive, which means that the water is not circulated. Active solar hot water systems work best in warmer climates where the temperature does not drop below freezing. If the climate where the system is being operated does get below freezing, an indirect circulation system can be used. This system utilizes a pump to circulate a heat transfer fluid that will not freeze throughout the collection system along with a heat exchanger which will heat the water so that it flows constantly.

The least expensive option is the passive solar water heating system, but this type of system is not as efficient as the active solar hot water system. The passive system is much more reliable and can last quite a long time. There are two types of passive systems including:

• * Thermosyphon system: Where water flows in the system and the warm water rises to the top while the cool water sinks. The collector system needs to be installed below the tank where the water is stored so that the warm water will rise inside the tank. While these systems are completely reliable, contractors must pay attention to the design of the roof of the tank because the storage tank is quite heavy. These types of systems can be more costly than a passive collector-storage system.

• * Integral Collector-Storage passive system: if you reside in an area where the temperature does not go below the freezing level then this type of system will work well for your needs. These systems are also good for homes that require larger amounts of hot water.

Storage Tanks / Collectors for Solar Energy

The solar hot water system requires a very well insulated tank to store the hot water. These tanks usually have extra inlets and outlets which are connected to the collector. If the system has two tanks, then the water is preheated before it enters a conventional water heating system. If there is only one tank in the system, then the back up heater is contained in the single tank with solar storage.

There are three solar collector types which are used for residential needs:

Evacuated-tube – this type of solar collector has rows of glass tubes which each contain an outer glass tube and a metal absorber tube which is affixed to a fin. The coating of the fin helps it to absorb maximum solar energy and prevents it from losing that heat. These types of systems are used most often in the commercial applications.

ICS or Integral Collector-Storage – these systems have one or several black tanks and tubes together in a glazed and insulated box. The cold water moves through the solar collector, preheating the water. The water moves on to the regular water heater which ensures that there is a constant supply of hot water. These types of systems should only be used in climates that have mild freezing because any pipes located outdoors could freeze if the weather is extremely cold.

Flat-Plate – these insulated, weatherproofed boxes feature a dark plate that absorbs heat below a plastic or glass cover. Flat plates used for solar pool heating have a dark plate for absorption constructed of metal or polymer and do not have an enclosure or a cover.

Although solar hot water systems can save a great deal of money, the homeowner does still require a backup system for those days when the weather is overcast, and no direct sun can be utilized. The water is stored in a conventional storage water heater which offers extra backup of hot water when none can be gathered from the solar water system.

When you are trying to decide on a solar water heater you should conduct some simple research to know what type of system will work best for you. First, you will need to estimate the cost of the system as well as how efficient will be for your needs. You will also need to know the amount of solar resource that your site is exposed to so that you know how efficient the system will be. You need to know the size of the system that you will need to serve your hot water needs. Lastly, you need to know the regulations of your local municipality along with the codes and covenants that will apply to the installation of such a system. There are various parts that are required for solar hot water systems including heat exchanges and heat transfer fluids.

Installation and Maintenance of the System

Solar water systems need to be properly installed and that installation will rely on several factors. Those factors include the climate, the requirements of your local building codes, the amount of solar resource that you can access and the various safety issues.

Once the system has been installed, it needs regular maintenance so that it will run correctly. If the system is passive, it does not require a great deal of maintenance. If the system is active, then you will need to understand what the requirements are from the system provider and ensure that you are undertaking the proper maintenance procedures.

The maintenance required on a solar hot water system can be done once every 3 to 5 years and should be undertaken by a contractor who understands solar systems. The systems that have electrical components generally require replacement parts in about 10 years.

Having Solar Hot Water Systems Installed:

If you are planning to have the system installed by a contractor, there are some basic questions that you should look for in a contractor when it comes to installation and maintenance, for example:

• How many years has the company with the installation of solar systems and the maintenance of them?

• Do they have a list of customers that will offer references?

• Does the company have experience with the installation of the specific system that you want installed?

• Does the company have the proper certifications or licensing required for the installation of the system you want installed?

• Does the company offer maintenance of the solar hot water system you want to install?

Once your solar hot water system has been installed, you might need back up systems also installed so you should have those devices or systems installed at the same time so that you have a more cost-effective installation experience.

Images from Refined Plumbing Sunshine Coast