4 Different Kinds of Solar Water Heater
One of the most recommended water heaters worldwide is the solar water heater. This is due to the series of benefits it provides to its users. For instance, since it uses the sun’s energy to heat water, electricity bill will likely reduce to 80%. Moreover, the environment could also take advantage of it due to the reduction of carbon footprint. Solar water heater has different types suitable only for a specific area or situation. Aside from knowing its types, it’s best to know its features as well. To help you about it, here are some of the four known types of solar water heater:
- Thermosiphon system
Thermosiphon is a type of solar water heater that has the capability to heat water and antifreeze fluid such as glycol. In addition, the fluid elevates by a natural convection that comes from the solar collectors to the storage tanks. These are mostly installed in higher areas. Opting for thermosiphon system, no pumps are needed. On the other hand, there’s a fluid movement and heat transfer that arises along with the temperature. With that being said, thermosiphon is a system suitable for places with high levels of solar exposure.
- Direct-circulation systems
In contrast to the thermosiphon system, direct circulation system needs a pump to operate. The aforementioned is used to pump water coming from the storage to the collectors during sunny hours. Moreover, freeze protection is obtained by recirculating hot water from the unit’s tank or through flushing the collectors. The energy consumption increases due to the recirculation while the flushing procedure reduces the hours of operation. Direct-circulation system is only utilised in areas where there are infrequent cold temperatures.
- Air system
When the air system operations, the collectors will heat the air. This is moved by a fan by an air-to-water heat exchanger. After this, the water can be used for household purposes such as cooking and laundry. Lastly, the efficiency of the heat exchanger is deemed to reach up to 50% range.
- Drain-down systems
This type of solar water heater is also known as an indirect water heating system. The water, regardless if it’s treated or untreated will be circulated through a closed loop. Then, heat is conveyed to a potable water through a heat exchanger if there are situations having more than 85% efficiency. When there’s no solar heat available, the collector fluid will drain because of gravity. This is a way to prevent convection loops or freezing. Most of the time, the most common fluids being used for freeze protection purposes are the water-ethylene glycol and water-propylene solutions.
Pump-activated, thermosiphon and direct-circulation systems require constant maintenance especially when the area experiences freezing temperature. In addition, indirect air and water system are more suitable for most countries. On the other hand, even if air solar systems are more efficient in contrast to water systems, you might want to opt for the latter if you’re more concerned with the cost maintenance since it neither burst nor leak.