How Solar Water Heaters Work Vol.1:

A Guide by SUMMER

We at SUMMER deal in the business of solar water heaters. It’s been our modus operandi for over 44 years and our commitment to that is something we are very proud of. With the continued battle against climate change and the general public’s increased interest in renewable energy, we thought it’d be appropriate to throw our hat in the ring on explaining how exactly our solar water heaters work. In this blog, we’ll be detailing all things solar water heaters. We know this blog is all about solar water heaters to begin with, but this is about the solar water heater itself. 

Understanding Solar Water Heater Technology 

 Overview of Solar Collector Types 

 Flat-Plate Collectors: 

Flat-plate collectors are the stalwarts of solar water heating systems. These collectors consist of a dark absorber plate, typically made of metal, that absorbs sunlight. A transparent cover, often made of glass, traps the absorbed heat, creating a greenhouse effect. These collectors are versatile and commonly used in residential and commercial applications. 

Evacuated Tube Collectors: 

Evacuated tube collectors employ a different design, consisting of rows of glass tubes containing an absorber plate. These tubes create a vacuum, minimizing heat loss and enhancing efficiency. This design excels in colder climates and has gained popularity for its ability to capture solar energy even on overcast days. 

Concentrating Collectors: 

Concentrating collectors focus sunlight onto a small area using mirrors or lenses, intensifying solar energy. This concentrated heat is then transferred to a fluid, typically used in industrial applications or large-scale power generation. While powerful, concentrating collectors are more complex and are often utilized in specialized settings. 

How Collectors Convert Sunlight into Usable Heat 

As the name and infodump above suggests, these collect sunlight. From that, when the sunlight strikes the absorber plates within the collectors, it begins generating thermal energy. This energy is then transferred to a heat transfer fluid, usually a mix of water and antifreeze, circulating through the collector system. Below, we’ll talk more about what’s so important about these “absorber plates” and fluid circulation in this process. 

Importance of Absorber Plates and Fluid Circulation in the Heating Process 

Absorber Plates: 

The absorber plate play a pivotal role in this conversion process. Its dark surface maximizes absorption, ensuring efficient utilization of solar radiation. Materials with high thermal conductivity, such as copper or aluminum, are commonly used to enhance heat transfer from the absorber to the circulating fluid. 

Fluid Circulation: 

Fluid circulation within the collector system is crucial for transporting the absorbed solar heat to its intended destination. This continuous flow ensures that the captured energy is efficiently delivered to the water or heat exchange system, contributing to a consistent and reliable supply of hot water.

And with that, you know the components of what’s in a solar water heater.  Most solar water heaters operate with similar rules and principles to what we showed here today, but despite the mountain we’ve presented, this is only the beginning. In our next entry, we’ll talk about how exactly all of that allows us to harness solar energy for our SUMMER solar water heaters