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 Available
Flat-plate collectors The 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 collectors
The 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 pump
Unlike 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 mount
This 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 system
Similar 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 Costs
Each 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
A flat roof
All solar panels must be angled in the direction of the sun; this can be difficult if your roof is flat. In this case, you will need to tilt the panels in the right directions which can cost you an additional $20 to $80 per panel.
Roof condition
If your roof is old or not in a suitable condition for the system to be installed on, you will need to do additional work before installation. This will contribute to your overall cost.
Installer demand
As the need for solar hot water systems rises across Australia, installation is in high demand. Depending on the season and demand for these systems, your overall price could fluctuate.
Solar panel quality
Depending on your exact requirements, you may need a specific type of panel. The more effective solar panels cost more but will save you money long-term.
Whilst some may argue that solar hot water systems are costly to purchase, they are far cheaper to run than electric or gas storage water heating equivalents. The cost of running a solar hot water system can vary depending on a variety of factors including location, temperature, and energy tariff. Research shows that on average, a household can expect approximately 50-75% reduction in their water-heating bill after switching to solar.
Why Choose Solar
There are many reasons why solar water systems are becoming more and more popular in Australia. Not only is domestic water heating in most Australian homes becoming increasingly more expensive, but it is also the highest contributor to greenhouse gas emissions. Solar hot water systems can help you reduce your carbon footprint and also help you save a fair amount of your hard earned dollars, every year. Furthermore, installing these systems in your home is known to increase the value of your home by attracting healthy government rebates. Given Australia’s warm climate, hot water systems in our climate are likely to provide up to 90% of your hot water requirements. Even on less warm days, your system will continue to work, especially evacuated tube systems, which are made to work efficiently in any weather condition. If installed and maintained correctly, solar hot water systems are a revolutionary household item that is exceptionally reliable and safe. Is a solar hot water system the right choice for me? If you are currently living in a dry and warm area, then a solar hot water system is perfect for your home. While payment upfront is more expensive, the long term cost saving will be well worth it. For those who live in the colder Australian temperatures, installation and usage of solar hot water systems is more complicated. Most homes in cooler climates will likely still be able to enjoy the long-term savings, provided the system is installed correctly. If you are unsure, it is best to get a full assessment and quote to ensure you are making the right choice.
