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Answering your frequently asked questions


The Economic benefits of a Solar Water Heater

Water heating requires energy. Whether you need to purchase that energy or not depends on whether you have a solar water heater. With a Solahart solar water heater you can expect up to 95% of your hot water energy needs free from the sun. That percentage is related to the climate and the type of solar water heater you own.
If you do not have a solar water heater, 100% of the energy you need must come from some form of purchased fossil fuel.
The difference between using a solar hot water system and a gas or electric system has economic, and of course, environmental implications. (See Fact File 007 for the environmental benefits.)

The Economics

The economic benefits of using a Solahart water heater depend on geographic location, lifestyle and type of system. The energy contribution made by the sun (costs saved compared to using a conventional electric water heater) can vary up to 95%, depending on the Solahart model and the location. Whatever the location, these are significant energy costs saved by using the sun.

A solar water heater is a long term investment. Solahart products are warranted for either 5 or 12 years depending on the model. In practice, the life expectancy may be longer than 12 years depending on usage and water quality.

It is possible to do simple calculations that will compare energy savings with the capital cost and arrive at what is known as a "payback period." However, there are actually very few consumer items that such analyses are done on and it may be difficult to get any accuracy because costs depend on such factors as pattern of usage, quantity of water used and cost of energy.


A Solahart solar water heater is a long term investment.

Given the long expected lifetime of your Solahart quality solar water heater, comparisons can be made with cheaper, shorter lifetime gas or electric systems. A good quality solar water heater such as a Solahart can have the lifetime of 2 or even 3 cheaper heaters. There is of course no "payback" with an ordinary hot water heater - it remains a cost item to the household budget forever.  The economic benefits of solar water heaters are long term.

Comparing Water Heaters

From the economic point of view, there is no question that solar water heaters perform better. They use less purchased energy. The calculations are simple. The comparison shown in the graph is between a range of electric and gas storage water heaters and the Solahart BC XII model with an average daily water usage of 200 litres, and a standardised climate.

With a Solahart solar water heater you can expect up to 95% of the energy needs free from the sun.

The Solahart BC XII uses nearly six times less energy when compared to a standard electric storage heater, and over twelve times less when compared to a standard gas storage heater.  The actual cost savings depend on electricity and gas costs, but a good quality solar water heater always costs less to run.

There are also less tangible economic benefits.  If you own a Solahart solar water heater, you make less demand on the energy supply system.  In the end, a wider usage of solar hot water systems means less resources need to be spent on energy infrastructure.

Anyone who purchases a Solahart system is making a long term investment by using free energy from the sun, and spending far less on purchasing fossil fuel energy.  It makes sense for the family, it makes sense for the community.



Estrada do Algueirão,  31-1º  Dto.
2725 Algueirão - Portugal
Tel. (351)  21  922  9540 - Fax (351)  21  921  0418
Email:  solahart@digal.pt