Active or Passive Solar Water Heater?

Mon, 30 Aug 2021

solar water heater hardware

Everyone has to use electrical energy to power their home appliances. This racks up bills that can leave the homeowner with a hole in their pocket. To save on energy costs, many homeowners in Malaysia choose to install a solar water heating system -- a very practical move as the country is bathed in sunlight all year round.

However, with different types of solar heater systems on the market, such as active and passive, choosing the right one can be confusing for the uninitiated mind. In this post, we are pleased to provide you with an analysis of active and passive solar water heaters to help you decide which one suits you best. 


Active and Passive Solar Water Heater Mechanics

The main difference between active and passive solar water heaters lies in their mechanics. 

Active solar water heaters use an internal electric circulation pump and valve system to circulate water throughout the unit. 

Passive solar water heaters depend on gravity and the tendency of hot fluid to rise to distribute hot water throughout a home. Heated water rises to the upper tank without using external energy to transfer heat from the solar collector to the storage tank.


Advantages and Disadvantages of Active and Passive Solar Water Heaters 

Certain features make each of these solar water heaters desirable. After reading through the pros and cons, you will be able to make a well-informed decision regarding which unit you want. 

1. Cost

Active systems cost more than passive ones because of the internal setup of electrical components. Opt for a passive solar water heater if you want to save money when purchasing your solar water heaters. 

Although passive units are cheaper, the cost is also dependent on the size of the hot water system. Still, in general, they are more affordable than active systems.


2. Efficiency

Active solar hot water systems can function effectively in cold regions. They may have environmentally friendly antifreeze to transfer heat to the water, and they work as long as there is electricity.

Passive solar hot water systems require solar energy from the sun to function, making them less effective in cold regions. When there is no sun to supply the collectors with heat to be transferred to the water tanks, there will be no hot water to distribute throughout the house. Passive units are more effective in warm areas.


3. Maintenance

Active solar water heaters need regular maintenance to keep them up and running, and the maintenance charges can be quite high. Passive water heaters require less maintenance and are more affordable.


4. Spaciousness

Active water heaters take up more room inside a home. On the other hand, passive units take up less room because they are installed outside on the roof to collect direct sunlight.


5. Impacts on the Building 

Passive units are massive so that they can collect enough water to circulate throughout the house. More so, they have to be located up high on a building. They are usually installed on the roof in order to get enough sunlight to heat the water in the collectors.

The weight of this unit can have an impact on the building, causing damage. If you have a weak roof, you should avoid the passive unit.


Final Takeaways

If you live in a warm climate country such as Malaysia, a passive solar water heater is a better choice. You can make use of a sufficient solar energy supply to heat your home’s hot water system.

However, if you live in a cold area, an active solar water heater is more reliable. For further details regarding solar water heating systems, feel free to get in touch with our specialists for a full consultation.