What Is A Solar Hot Water System?Solar energy is one of the earth’s primary energy sources, an integral part of making our planet habitable by contributing significantly to plant growth through photosynthesis.Solar hot water systems are unique due to their ability to utilise energy from the sun to generate heat. This energy produced from the sun can be used to heat water for showering, space heating, solar cooling, or industrial processes.Solar hot water systems have the capacity to provide between 40–90% of your homes’ hot water requirements and are particularly useful in warmer climates that have high levels of sun exposure.Despite being around for 100’s of years, solar hot water systems have advanced significantly in the last 20 years. Absorber coating technologies have resulted in solar collectors that can efficiently convert approximately 50% of sunlight into a hot water supply which can be used throughout your home.One of the main benefits of using solar hot water systems is their ability to cut your household’s carbon footprint. Another key advantage of choosing a hot water solar system is the long term financial saving you get from reduced energy costs.
Types Of Systems AvailableFlat-plate collectorsThe flat plate collector system is considered the ‘traditional’ solar system. It uses a large solar-like collector to collect the sun’s heat rays and transfer them to an insulated hot water tank. This system has been acclaimed for offering a reliable supply of hot water for homes where evacuated tubes may not be feasible.Used for both residential and commercial purposes, the solar panel can be mounted onto the roof and is then connected to a solar geyser. Once the sun’s rays heat the panel, the water begins to heat and automatically rises to the top of the solar panel. From there the hot water it is fed into the solar geyser and is ready to be used in your home.What draws people to flat plate collectors is the fact that they are the more affordable of the solar hot water systems. Unfortunately, while they are more affordable, they are unlikely to work in cooler temperatures.Evacuated tube collectorsThe evacuated tube collector combines evacuated tubes with the rapid transfer capacity of heat pipes to create a system that can be used efficiently in just about any climate, ideal for both residential and commercial use.This system is run by attaching a series of cylindrical glass tubes to a frame installed on your roof. Thereafter, a chemical inside each tube will begin to boil when the temperature reaches anywhere between 30-40°C. This leads to the copper rods inside each tube heating up, resulting in the water passing through the manifold to heat up as well. Some evacuated tube systems connect directly to the solar geyser instead of going through a manifold.This system is slightly different to other solar hot water systems in that can be utilized as efficiently in any climate, hot or cold.Heat pumpUnlike the other main solar hot water systems, heat pump systems are unique in the way they collect sunlight. Heat pump systems draw heat from the air instead of directly from the sun, and use this to heat water. There is a small level of electricity needed to pump in hot air, but most consumers have argued that it is a tiny and almost negligible amount.Research shows that heat pump systems require approximately one-third of the energy needed to power up a conventional household geyser with the same amount of litres. This can result in astronomical energy saving within a household, up to approximately 70%.Roof mountThis entire system exists entirely on the roof of your home, including the storage tank and solar collectors. Most of these systems should be installed in a northerly position, ensuring maximum solar heat retention. Once the water is heated, it will be made accessible to you through mains pressure delivery.As the hot water in your house gets used up, cold water will travel through the solar collectors, heating up and refilling your storage tank with hot water. This ensures you will have access to hot water 24/7.Split systemSimilar to the roof mount systems, split system solar collectors are generally also installed facing north. The main difference is that the water storage tank is installed on the ground instead of the roof and is usually mounted near any area where hot water is used regularly, i.e. bathroom or laundry room.As the water is heated, a circulation pump is activated, which moves the water into the storage tank. Like most solar hot water systems, as hot water travels in, cold water travels out, ensuring you always have access to hot water.
Solar Hot Water System Purchase And Running CostsEach fully installed solar hot water system costs on average between $3,000 and $7000, depending on which system you require. When you are working out the overall cost of a solar hot water system it is also important to factor in the fact that each of these systems will likely cut your hot water heating bill by 70-80%, in the long run.Additionally, solar hot water systems that require gas boosters will cost between $500 to $1,000 more, in comparison with systems using electric boosters. Split systems are also known to be slightly more expensive than roof mounted systems.On average, non-solar hot water systems cost anything from $300 to $2,000. Comparatively, solar water systems prices range, as seen below:
- Flat plate collector: Prices begin at around $3,000 and generally will not exceed $4,500.
- Evacuated tube collector: Prices start at approximately $6,000
- Heat pump: Prices range between $3,000 and $4,000 (the more affordable of all the systems)
- Roof-mounted: Prices start at $2350, and can increase depending on litre size
- Split system: Prices start at $2625 and can increase depending on litre size