Active VS Passive Solar Water Heating System: Know The Difference
There are several types of solar water heating system that are commonly used nowadays. But the important thing to know is these systems are always a bit different from each other. Which solar water heating system meets your requirements is what you need to know. Among the types of solar water heaters, the two most common types are active solar water heater and passive solar water heater. In order to know, which one would suit you the best, read on to find out their differences.
One of the main difference between these two types of solar water heating system is that, on one hand, the active system uses a pump to move the liquid through the systems. On the other hand, the passive system mainly relies on gravity to move the liquid. Active systems usually use environment-friendly anti-freeze in order to transfer the heat energy to the water. This is something a passive solar water heater does not do.
Another difference is the solar collectors. In a passive solar water heating system, the water is heated in the solar tubes that are exposed to the sunlight. If you need hot water, a latch opens up, and the hot water moves freely from the pipes to the outlet. For an active system, solar collectors are different. The hot water is heated using these collectors and then there are two things which the pump does. The hot water is either transferred to the storage tank or the anti-freeze is transferred to a coil in the tank. This coil then heats up the already stored cool water in the solar tank.
An active solar water heating system uses external sources like electricity to start the pump. But a passive solar water heating system does not rely at all on any external resources and only uses the heat absorbed from the sunlight. This is why, in case of bad weather conditions; a passive system might not be effective enough to produce hot water. But, on the other hand, as it does not use external sources, the water you would be using will be free of cost entirely.
Therefore, both active and passive solar water heating system has its own negatives and positives of their system. If you live in a place where you face a lot of bad weather conditions, it is best to use an active one. On the other hand, if you don’t face any severe weather conditions, but you want to be free of external sources totally, you should go for a passive solar water heating system.