Solar Hot Water

What is Solar Hot Water?

High efficiency solar collectors on the roof of your home, capture the sun, which heats the water in the solar hot water system. The hot water is then stored in a tried and proven tank and can then be used for showers, cleaning or heating your home. It’s that simple. At this location, we are going to learn why using the sun to heat our water is so good for our environment.



Running a solar hot water system is environmentally friendly. The Greenhouse Effect is the most pressing ecological problem facing our planet.

One of the most cost effective ways to reduce greenhouse gas emissions is to minimise our consumption of fossil fuel generated energy.

A clean, green energy source is solar and a solar hot water system is the perfect alternative for your hot water solution.

How does it work?

Solar hot water systems capture the sun’s energy to generate heat.

“Closed loop” systems, which are preferred in cold climates (where freezing temperatures are common), utilize flat panel solar collectors and a non-toxic heat transfer fluid to collect heat. A heat exchanger is used to transfer the heat, then a system of valves, pumps and controllers circulate the heat transfer fluid throughout the collector. Thereby heating water in the storage tank.

The heated water is then useful for everything from washing laundry to heating a pool. Solar hot water systems are up to three times more efficient than photovoltaic cells! That means solar hot water systems are one of the best uses of solar energy when it comes to efficiency and cost-effectiveness.

Water heating accounts for almost 30% of the average household’s energy usage. Getting your hot water free from the sun not only saves energy, it also saves the greenhouse gas emissions that would have been produced in the generation of that energy. By replacing an electric storage water heater you can reduce greenhouse gas emissions by up to 3.5 tonnes a year depending on the system and your situation.

Did you know?

Solar collectors collect direct sunlight as well as solar radiation. So, even on cloudy days, there is ample solar radiation to provide significant performance.

Solar hot water systems are up to three times more efficient than photovoltaic cells!

Solar hot water can even be used to heat the house or pool. Go Solar Go!

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Types of Solar Hot Water Systems

There are two types of collectors used with solar hot water:

* flat plate collectors (suitable where tank mounting is required)

* evacuated tubes (more efficient and great for frost prone areas)

Flat plate solar collectors

Flat plate collectors work on copper pipes running through a glass covered collector, often connected to a water storage tank on the roof. The hot water can then thermo-siphon itself in and out of the tank, thus heating the water.

Evacuated tube solar collectors

Evacuated tubes use a glass tube with a vacuum inside it and copper pipes running through the centre. The copper pipes are all connected to a common manifold, that is then connected to a slow flow circulation pump, which pumps water to a storage tank below. Thereby, heating the hot water during the day. The hot water can be used at night or the next day due to the insulation of the tank.

Solar hot water systems may be used to heat water for a wide variety of uses, including home, business and industrial uses. Heating swimming pools, underfloor heating or energy inputs for space heating or cooling are more specific examples.

Solar HOT Water to the GLOBAL RESCUE.

Avoids 3,000 kg of CO2 per year (equivalent to a small car).

* Saves 30% of your household greenhouse gas emissions.

* Slashes (AUS) $300 to $700 off your energy bill each year.

* Reduces the impact of ongoing electricity price increases.

The Facts

There are many ways to save water.

- The use of water saving washing machines.

- The use of water saving toilets.

- Avoid planting water loving plants.

- The use of native grasses that do not require a sprinkler system.

- Replace your showerhead with an ultra low-flow version.

- Turn off the tap when brushing teeth or shaving.

97% of the water on Earth is salty ocean and 2% is frozen.The remaining 1% is available to meet the needs of plant and animal life which includes all of us humans.


QUIZ 10: Solar HOT Water

Solar Hot Water is one of the best solutions we have to reduce our personal and collective CO2 emissions. The sun provides a constant source of

energy. We only need to capture it or convert it. Helping the planet also means you get to save time, money and energy, which is a winner for everyone! Are you ready for the next quiz? Most of the answers can be found in the previous section but some questions may require you to dig deeper. So, consider the internet, go to the library or ask a friend. Happy energizing!

1. What is solar hot water and how does it work?

2. How does solar hot water help to reduce CO2 emissions?

3. What are the two types of solar hot water systems?

4. Can solar hot water still work when it's cloudy?

5. List 3 ways you can save water today.

6. True or false. Solar hot water can be used to heat the house and the pool?

7. True or False: The Earth receives enough energy from the sun in 1 hour than humans use in an entire year?

8. Activity: Use a bucket to measure how much water comes out of your shower in 15 seconds and multiply that figure by 4 to give you the amount of water used in 1 minute - How long was your shower today?

- How much water did you use in the shower?

- How much water would your family use per day?

- Now multiply this figure by 365 to work out your households water usage for the year.

9. Describe what a grey water system is?

10. Can a grey water system utilize your used shower water?

11. Does your school use solar hot water? Form a committee today to make it happen and remember there

are many government programs to help you achieve this.

Solar Word Find (image)

1. Solar Hot Water systems utilize energy

from the ... to heat water?

2.Solar Hot Water systems heat water up

using a .....?

3. True or False? The sun contains most

of the mass in our solar system?

4. True or False? A Solar Hot Water system

can produce hot water equal to a gas or

electric system?

5. Solar panels often go on the ....?

6. Solar hot water can even be generated

on ...... days

7. Solar hot water can NOT be generated

at .....?