A hot water solar system is a great way to reduce your carbon footprint and reduce your energy bill at the same time. But if you already have a solar PV system, you don’t need to get a solar water heater.

When it comes to heating water for household use, solar thermal used to be the best option until the PV panels’ price dropped drastically. Thus, generating electricity and boiling water at home with solar is a lot easier to do than ever.

If you’re interested in hot water solar systems, keep reading.

This article discusses solar thermal systems, when to get them, and when to choose a solar PV system instead. 

We’ll also outline some of the disadvantages of solar water heating systems and the next steps for homeowners ready to switch to solar power.

What is a hot water solar system?

A hot water solar system uses solar energy to heat water. 

Given the abundant sunshine in Australia and government solar incentive, many Australians now realise the benefits of going solar. 

One top reason to go solar is the environmental benefits because they reduce your reliance on fossil fuels. 

In addition, solar water heating systems are a popular choice among homeowners because they are cost-effective.

How does a hot water solar system work?

Generally, there are two types of solar-powered water heating systems: solar thermal water heating and solar PV. How a hot water solar system works depends on the system used. 

How solar thermal water heating works

Solar thermal water heating system consists of three main components:

A collector converts sunlight to heat 

Solar collectors absorb sunlight that is converted into heat energy. The heat is then transferred to the storage tank.

The collectors are of two types:

  • Active collectors: These use pumps, controls, re-circulation lines, and valves to heat the storage tank on demand.
  • Passive collectors: These don’t require pumps or active controls because they rely solely on gravity to circulate water through pipes inside the collector. 

A tank stores the heated water

The size of the storage tank depends on how much hot water your household uses throughout an average day. 

A controller regulates water flow into and out of the tank

It ensures that your system operates safely and efficiently throughout the day.

How solar PV water heating works

A solar photovoltaic system, also known as a solar PV system, uses solar panels to convert sunlight into electrical energy. 

Note that solar PV is not just a traditional water heating solar system. It is a full-scale electricity-producing system that can be optimised with a water heating system. 

Solar PV systems are made up of solar panels, an inverter, wiring, and a mounting system. 

The panels are connected to the inverter, which converts the DC power produced by the panels into AC power that your appliances and electronics can use. 

Solar PV systems can either work on or off the grid

A grid-tied solar system works in tandem with your existing energy provider and exports excess electricity for a feed-in tariff. 

If your solar water heater is grid-tied, you want to learn how to read your electricity bill after installing solar. 

An off-grid solar system works like a typical home generator. 

But instead of powering your home directly from the mainline, an off-grid system generates its power with the help of batteries that store excess energy produced by your panels.

Solar PV systems are becoming increasingly popular due to their low cost and environmental impact.

Types of hot water solar systems

There are three types of solar hot water systems:

Evacuated tube collectors 

Evacuated tube collectors are one popular type of solar heater.  They use two vacuum-sealed glass tubes. The inner tube is the water pipe, which runs through a heat exchanger at the centre of the outer tube. 

As sunlight heats the air between these two tubes, it’s transferred to the outside of the inner tube through convection. This process helps keep your water hot even on days when the sky is overcast.

Collectors made from evacuated tubes are relatively easy to maintain and require no additional hardware to work correctly. As a result, they’re one of the most efficient types of solar panels available today. 

The flat-plate collector system 

The flat-plate collector system has a panel–like surface area that catches the sunrays and transfers heat to a water tank. 

It can be installed outside and manually moved throughout the day to face the sun, or it can sit directly on top of your tank and provide instant heating as soon as you turn on your faucet.

Some flat-plate collectors are made from dark-coloured metal that absorbs sunlight quickly. While these panels tend to lose heat faster than those covered in glass, they take less time to heat up when the sun is shining.

Heat Pump systems

Unlike conventional solar hot water installations that capture sunlight, solar heat pump systems utilise air to heat water. 

Heat pump solar systems consume electricity to pump hot air into the system, although this is a minor amount.

Solar thermal or Solar PV? Which is better?

When it comes to solar water heating systems, there are two main types: solar PV and solar thermal. Solar PV systems use panels to convert sunlight into electricity, while solar thermal systems use panels to collect heat from the sun.

Solar thermal systems are a great choice for homeowners who want to save money on their energy bills. These systems are affordable and easy to maintain, and they offer long-term savings on your utility bills. 

However, solar PV systems offer several advantages over solar thermal systems: 

  • 1. Solar PV systems are more efficient than solar thermal systems 

If you live in an area with little sunlight throughout the year, it may be better to get a solar PV system because it’s more efficient at converting sunlight into electricity.

  • 2. You can use solar PV systems to power electrical appliances 

If you use many electronic devices in your home, solar PV panels may be a better choice for solar savings than solar thermal systems.

  • 3. Solar PV panels are more durable 

It makes these panels an excellent choice for homeowners who want to use their solar system as part of an emergency preparedness plan.

  • 4. Solar PV panels are much lighter than solar thermal systems 

So, they are much easier to install on your roof or the ground outside your home.  

  • 5. Solar PV panels generate more electricity than solar thermal systems in an average year 

And the amount of energy they produce increases each year as new technology is developed.

The solar collectors (in solar thermal) typically stand about 10 feet tall when fully mounted, so passersby can see them if they aren’t concealed in trees or other natural features. 

When choosing between a solar PV and a solar thermal water heating system, several variables can help you determine which is best for your home. 

Keep reading to find out!

One of the most common questions homeowners have is how much solar heaters will cost, especially those who do not know how solar pricing works

How much does hot water solar systems cost?

The cost of a solar water heating system will vary depending on the size, type of system you choose, and your location in Australia. 

Most hot water solar systems cost between $2,300 and $8,600 to install, while solar PV systems cost between $2,900 and $14,100

This may seem like a lot of money at first, but the system will pay for itself in the long run, and you can take advantage of government incentives to reduce the installation cost. 

For example, homeowners in Victoria can receive up to $450 per kilowatt in STCs. So you can buy a $9,600 6kW system at $6,902.

Instyle Solar Australia has created an easy-to-use calculator so that you can get a savings estimate for your specific location.

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When should you get a solar hot water system?

Water heating usually consumes about 25 % of electricity in Australia. So when you are looking to cut that cost off your electricity bill, consider installing a solar water heater system. 

You may also want to take advantage of the Victoria solar hot water incentive.

The program offers eligible Victorians a 50% rebate of up to $1,000 to install hot water systems.

Advantages of a solar water heating system

Hot water solar systems offer numerous benefits to homeowners:

They are long-term investments

The cost of installing a hot water solar system, either a solar PV or solar thermal can be intimidating. But the investment pays off in the long run. 

If you’re using a solar PV, you will require no additional cost for a hot water solar tank which makes solar water heating even more cost-effective. 

They are environmentally friendly

Hot water solar panels are powered by the sun, so they don’t release any greenhouse gas into the environment. 

They are easy to maintain

Hot water solar systems require little or no maintenance because they don’t contain any mechanical parts that run on electricity. Since there aren’t any moving parts to a hot water solar system, you don’t have to worry about extra maintenance work.

Hot water solar collectors should be cleaned once or twice per year to remove debris from the panels, but these cleaning tasks only take a few minutes to complete.

When don’t you need a solar water heater?

There are a few situations when you may not need a solar water heater. These include:

  • If you only use a small amount of hot water each day

A solar water heating system may not be the best option for you. Solar systems are designed to provide free hot water for an entire household, so they may be overkill if you only use a little bit of hot water each day. 

A solar PV system will be a better investment in such a case.

  • If you live in an area without access to sunlight

While some types of solar heating systems can be used during the winter, these systems are less effective than grid-tied PV systems that work throughout the entire year. 

  • If you buy PV solar

A PV solar system will produce the electricity needed to heat your water and run your appliances. So in such a case, you don’t need to install a solar hot water system.

Disadvantages of solar water heating systems

While solar water heating systems have many benefits, they also have a few disadvantages:

  • They may not be effective in cold climates

Solar water heating systems are less effective in cold climates because the panels may not provide enough hot water for your needs.

  • They can take a long time to pay off

You won’t see these savings until years later because you’re only saving on water heating. With a solar PV system, you’ll see your savings sooner because you save on all your electricity uses. 

  • If most days are cloudy

Solar heating systems in cloudy areas will require a backup option because they’re less efficient without direct sunlight.

In such a region, a solar PV system is more suitable because it’s good enough to work even on cloudy days.

Our Guides to Solar Panels and More

We have a series of unique guides to solar, solar finance, batteries and more, if you are looking to do more in-depth research into solar panels check the below:

1. What Are Solar Panels? How Do Solar Panels Work?

To explain this in simple terms, solar panels generate current when sunlight knocks electrons out of the atoms. This current then powers the entire house. Read on for a more in-depth analysis.

2. What Does PV Mean?

The term photovoltaic (PV) was first used in 1890. The term derives from the Greek terms photo, ‘phos,’ which means light, and volt, which means electricity.

3. What Solar Panels Do I Get? How Many Do I Need?

You might also be wondering what is the ideal number of solar panels for your home, and the answer depends on several factors.

4. How Do You Choose Good Solar Panels?

Are you looking for good solar panels for your home? If so, ensure that you choose the right solar panel for optimum efficiency.

Next Steps…

Interested in solar? By clicking below, you can use our smart solar calculator to find out just how much you could save with solar, what rebate you are eligible for, and the impact you will have on the environment.

Don’t wait until next quarter’s bloated bill, and get started today!

Click here to calculate your solar savings!

Join over 20,000 homeowners who have made the switch with Instyle Solar or the 1000+ positive reviewers who have been more than happy with their solar install.

Otherwise, you can always contact us on 1300 133 556 or email if you prefer at [email protected].

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