To calculate the time from which you will use your hot water for free, divide the cost of the solar system by the cost of the same service with another energy source.

The 190 liters TERMOSIFON system is suitable for hot showers for 4 to 5 people and has an approximate cost of **800 US$**.

The cost of a KWh (kilowatt hour) of public electric energy in Ecuador is about **0.20 US$** (incl. direct and indirect taxes).

The electric energy consumption for a person's shower is approx. 1.25 KWh per day.

The five people then consume 6.25 KWh per day, at a cost of approx. **1.25 US$** per day.

Energy consumption costs the family **37.50 US$** per month.

A year they have to pay for their hot water from the showers the sum of **450.00 US$**.

Sistema solar termosifón familiar

Dividing the approx. **800 US$** of the TERMOSIFON system for the annual cost of electrical energy of **450 US$**, results in **1,8 years**.

The cost of the TERMOSIFON system is paid in approx. **1,8 years**. So the family, which is using the TERMOSIFON system, has their hot water after less than **2 years** **FREE**.

It is worth mentioning that this amortization calculation is only applicable with equipment or systems that have a long useful life.

The TERMOSIFON systems due to their form of construction have a significantly longer life than other solar systems:

- Stainless steel tank

- Special glass vacuum tubes

- parabolic mirrors with special alloy

- Thermal insulation of the tank in polyurethane

- Nowhere with mechanical wear

- No moving part or parts

GR