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Answering your frequently asked questions


The Environmental Benefits of Solar Water Heaters

Solar water heaters are special. There are very few consumer products which have environmental protection built in as part of their function. Anyone who buys one has made a decision to protect the environment in their daily lives, as well as save themselves costs in water heating.

Using The Sun To Heat Water

Water heating requires energy. The source of that energy will be the sun if you own a solar water heater.

With a solar water heater you can expect to save up to 95% of your energy needs depending on your surrounding climate and the Solahart model you own. Even with cloudy skies there is still some solar energy for your use.

If you do not have a solar water heater, 100% of the energy you need must come from some form of purchased fossil fuel, and indirectly, you cause air pollution as well as using a resource which is finite.



The most environmentally friendly hot water system in the world.

The Environment

In Australia, it has been shown that if all the users of electric water heaters were to convert to solar, a massive 20% reduction of present greenhouse gas emissions would result. No doubt this figure is similar in other parts

of the world. The environmental benefit is clear. Each solar hot water system can prevent up to 4.5 tonnes of carbon dioxide from entering the atmosphere annually. This fact has been taken up by governments around

the world who have endorsed solar hot water systems as an important means of controlling greenhouse gas emissions. The Dutch government has identified Solahart as the highest performing system on the world market. (see "The Big Switch", by Gavin Gilchrist).

When you buy a solar hot water system, you take part in daily environmental protection.

Getting Better Results

Except in the very hottest of climates, solar water heaters require some form of booster and the choice is usually electricity or gas.

Using a gas booster is the most environmentally sound approach because there is a more efficient conversion of gas energy into heat. Solahart's patented 'Natural Wonder' gas booster system uses gas as required, without a wasteful pilot light.

Without a solar water heater, 100% of the energy you need to heat water must come from some form of purchased fossil fuel, and indirectly, this causes air pollution as well as using a resource which is finite.

Boosting can be made more efficient and cheaper by using a simple time switch with your solar water heater. The environmental impact is lessened also by using hot water in the early part of the day, allowing the sun to replenish the hot water rather than the booster.

Whether the owner of a Solahart system uses gas or electricity, they play a daily part in pollution reduction.

Embodied Energy

How much energy does it take to make all the components of a Solahart solar hot water system? How long will it take to recover that energy by using a Solahart system?

The answer is about eleven months, based on the Sydney, Australia climate and an average family using a Solahart BCXII model.

The embodied energy of a gas or electric water heater is never recovered.

Comparing The Efficiency Of Water Heaters

With a usage of 200 litres a day for the southern Australian cities (using standardised climatic conditions), it is possible to calculate the "coefficient of performance" (the amount of energy input compared to output) for a range of typical fossil fuelled water heaters and two Solahart products.

The results show that only the Solahart products have a continuing environmental benefit and efficiency. Ordinary water heaters, no matter how efficient, have a continuing environmental cost.


Comparing the energy input with energy output (all the water heaters below the line are a cost to the environment.)


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