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How to collect condensation with a water wise rainwater harvesting system

rainwater storage tanks collect condensation

One of the questions most frequently asked when considering the purchase of a Rainwater Harvesting System is whether it’s worth the effort or the expenses when living in an area with low rainfall, and when using it for irrigation, why use it when it is raining? The answer is YES on all fronts – and it is all because of condensation.

How does it work?

Condensation is nothing new. In fact, it is something we experience on a daily basis, whether drinking cold water from a glass, soft drinks from a can and even when we shower.  Condensation is when water changes from vapor or gas to its liquid form.  It occurs when warm air collides with a cold surface creating a dew-point that produces droplets of water.  It is this process that makes any Rainwater Harvesting System viable all year round, even though less water is collected during the warmer months, than during the rainy season.

How much water can a water tank collect?

Depending on where you live, you might just be surprised at how much water a rainwater harvesting system can collect during the dry season.  For instance, coastal areas will collect more water from condensation than other parts of the country.  Those living along the beach will find that the days are warm, but during the night the temperature cools down substantially. Inland areas with severe temperatures will benefit with only a slight drop in temperature, especially when catchment areas are in shaded areas.  A Rainwater Harvesting System can collect 3L of water from one square foot surface a day just with condensation.  It might not seem like a lot but over the total square area of your roof it adds up and this provides you with the opportunity to store water even when it is not raining.

Alternative water resource

A Rainwater Harvesting system does not mean you are not connected to your mainline water supply.  It is merely a secondary option that allows you to use more water at no additional cost and if you live in areas with water restrictions, it provides you alternative means of water apart from what your municipality allows. When your water runs low, simply switch back to your mainline water supply.

Invest in water saving systems

It is time to become water-wise at home