How Does A Solar Hot Water System Work?

With prices rising, solar energy is becoming a widely popular alternative source of heating for those looking to save on their electric or gas bills. Solar water heaters are also a great way to reduce your carbon footprint and help the environment.

At Jetset Plumbing, our team is passionate about getting you set-up with the best possible solution. So, if you're interested in solar hot water but unsure of whether it will work for you, call us on 1800 443 996.

How Does Solar Hot Water Work?

Solar hot water systems rely on a system of roof mounted solar collectors to absorb heat from the sun. This heat is then used to heat the water directly or it is transferred to a heat exchanger before heating the water. This step depends on the type of solar collector.

Once the water has been heated, it is then stored in an insulated tank until required. Depending on the type of solar water heater, this tank can either be roof mounted or stored on ground level.

Rooftop vs. Split Solar

Rooftop Solar System

Simply put, a rooftop solar system means both the solar collectors and the storage tank are installed on the roof. If you have the roof space for it, these solar systems are a great option.

These systems are more energy efficient as they rely on a natural thermosiphon effect rather than an inbuilt circulator.

In a rooftop solar system, cold water naturally flows into the collector or heat exchanger and then returns to the tank as it is heated. This works because cold water is more dense and therefore heavier than hot water.

The heated water is then stored in the insulated tank until it is needed.

Split Solar System

For this style of solar water heater, the solar collectors are installed on the roof while the storage tank is installed on ground level.

These heating systems rely on an inbuilt pump to transport the cold water to the collectors or heat exchanger. There it is heated before circulating back to the storage unit.

Again, the heated water then remains in the insulated tank ready for use.

Two Types of Solar Heating

When discussing solar water heating, indirect and direct are two terms often referred to. These reference the type of collector being used. For example, a flat plate collector heats the water directly as it travels through copper pipes. However, evacuated tube collectors transfer heat to a heat exchanger where the water is then heated.

Flat Plate Collector

Flat plate collectors are shallow rectangular boxes, usually consisting of a dark aluminium body covered with a glass panel, which house a series of copper pipes.

As heat is absorbed by the flat plate it is conducted through the copper pipes, meaning as cold water moves through the pipes it can be heated and then stored for later use in an insulated tank.

These collectors are more commonly used as they have a lower upfront cost, however the flat surface means that they are not always in the direct line of the sun.

Evacuated Tubes

Evacuated tube solar collectors consist of a series of vacuum sealed glass tubes which all have internal, thermally conductive copper pipes and heat absorbing plates. The sun's heat is absorbed by a dark absorbent coating and is trapped by the vacuum created between the two glass tube layers.

The internal copper pipes then transfer the heat to a copper manifold (or heat exchanger) where it can then heat cold water.

The tube shape means these collectors work at higher efficiency than flat plate collectors as they are always perpendicular to the sun.

Advantages of a Solar Hot Water System

Solar hot water systems are a great way to increase your home's energy efficiency and lower running costs by making use of Australia's abundant energy source; sunlight.

While the upfront costs are higher, a solar water heater can use up to 60% less energy than electric or gas systems, making the running costs one of its biggest advantages. Hot water typically makes up 25% of the energy used in an average Australian home. With solar energy being free, you are bound to notice a considerable difference in your energy bill.

Solar water heating systems are also known to be very low maintenance. As with any hot water system, it is still a good idea to have it inspected every few years but the actual maintenance requirements for these heaters are minimal. Solar hot water systems are also incredibly long lasting with an approximate lifespan of 15-20 years.

And of course, they are the environmentally friendly option, using a renewable energy source to heat as opposed to electric or gas.

So, thinking a solar hot water system might be the best option for you? Here at Jetset Plumbing we supply, install and maintain solar water heaters throughout Brisbane and the Gold Coast. Call us on 1800 443 996 and talk to the team about your solar hot water options today!