While the initial cost of solar water heaters may be a lot higher compared to conventional water heaters, the photovoltaic energy people harness can yield more environmental benefits and savings than other energy sources. Heating H2O accounts for 18% of a property’s energy use, but doing this using solar energy could cut the heating bills by 50% to 80%.
This article explains how solar-powered heaters can help property owners tap into a renewable and free energy source, possibly saving a lot of money, as well as doing well for the environment. With this info, people can make the best possible decision about whether this device is a good investment for the property’s water needs.
To find out more about how these things work, click here for more info.
What are solar water heaters?
The basic function of this device is to expose H2O or heat-exchanging liquids to photovoltaic energy, then circulate the warmed liquid back into the house for domestic use. The main components of these devices are storage tanks and collectors to help trap photovoltaic energy (PTVE).
Collectors are flat plates, tanks, or tubes through which water or heat-transfer fluid passes, as well as absorbing PTVE. The liquid is circulated to the heat-exchange unit or water tank from there. While these things are usually used as energy-saving gadgets to preheat H2O before entering traditional devices inside the house, some devices store and warm H2O without the use of traditional tanks, offering 100% sun-powered hot liquid.
Kinds of sun-powered heaters
These things are divided into two categories: active and passive. The main difference between these categories is that active systems need circulating pumps to help move the liquid, and passive systems solely rely on the earth’s gravity to move the H2O. Active systems also need electricity to run and may use antifreeze solutions as their heat-exchanger fluid.
To explain passive solar collectors in the simplest way, the liquid is heated in tubes and piped directly to the home’s faucets if needed. Active collectors use antifreeze (which is passed from the collector into the heat exchanger that helps heat clean H2O for household use and storage) or heat the liquid directly, which is pumped to the water tank. Passive and active systems have subcategories that are considered specialized for different budgets, capacities, tasks, and climates. The one that is right for people will depend on various factors such as:
- The installation budget
- Building regulations and codes in the area
- The capacity requirements
- Availability of the sun
- Available space
Let us take a closer look at each type of system and how it can benefit a residential property.
What is PTVE? Visit https://www.energy.gov/eere/solar/solar-photovoltaic-technology-basics to find out more.
Active heaters
Although these devices are more expensive than passive systems, active devices are considered the more efficient system. There are two kinds of active heating systems.
Direct
In direct systems, clean and drinkable water directly passes through the heat collector to storage tanks for use. They are best suited for climates where temperatures don’t usually go below freezing.
Indirect
Indirect systems circulate non-freezing liquids through the collector and into the heat exchanger, where the liquid’s heat is transferred to clean and drinkable H2O. It is then circulated into storage tanks for everyday use. These systems are needed for places with cold climates where temps usually go down below the freezing point. Without this system, pipes will run the risk of bursting and freezing.
Passive heaters
These devices are a more straightforward and less expensive option but also less efficient compared to its counterpart. But these things can last longer and be more reliable, so people should not overlook them as a good option, especially if they are on a tight budget. All passive devices use gravity or pressure to circulate liquids and come in two forms:
Batch and integral collector storage (ICS) heaters
An ICS solar-powered water heater is one of the most straightforward photovoltaic H2O heating systems on the market today. The collector serves as a storage tank and heating system. They are pretty efficient but only work in places with little risk of freezing temps.
It can be as simple as a big black tank or smaller copper tubes fastened to the property’s roof. Devices with copper tubes heat a lot faster because of increased surface area. However, it loses heat much faster because of the same reason. This device is used to preheat liquids for traditional heaters. In this kind of system, when H2O is needed, it leaves the collector or storage tank and enters a traditional heater in the house.
Thermosyphon devices
This thing relies on thermal circulation. The liquid circulates when warm H2O rises, and cold ones descend. It features tanks like ICS units, but has a collector system attached going downwards from the storage tank to allow the thermal circulation of the liquid.
Thermosyphon collectors gather photovoltaic energy, sending heated liquid back to the storage tank through a heat or closed-loop pipe. While it is more efficient compared to its ICS counterpart, it cannot be used where constant freezing happens.