Solar water heaters are used to heat the water by collecting the heat from the sunlight. This solar water heater is very useful to heat your water without using electricity. This system can save you money as you do not have to spend money on fuel or grid power.
What is a solar water heater?
A solar water heater will heat the water by capturing the sun’s heat and transferring it to the water.
This system has four main components;
- Solar collector
- Circulation system
- Storage tank
- Backup system
A solar collector is the component of the solar system that collects the sun’s heat. There are 3 types of solar collectors.
- Batch collector
- Flat-plate collector
- Evacuated-tube collector
The circulation system is the part of the solar water heater that is used to transfer the heat from the solar collector to the storage tank. There are mainly four types of solar collectors.
- Direct circulation system
- Indirect circulation system
- Active circulation system
- Passive circulation system
The backup system is used to heat the water when there is no sunlight for an extended period.
How does a solar water heater work?
The way the solar water heater works, differ according to the solar collector and the circulation system.
The basic working principle is that the solar collectors collect the heat and transfer it to the storage tank by the circulation system. This storage tank is well insulated. So the temperature of the water inside the tank will increase when the heat is transferred to the tank by the circulation system.
Is the solar water heater any good (Advantages of the solar water heater)?
Yes, solar water heaters have many advantages. By using a quality solar water heater you can experience all these advantages.
- No need for electricity from the utility grid– when using solar power you do not need to worry about getting the electricity from the utility grid. So you do not have to worry about having power outlets or installing power outlets where you want to fix your water heater.
- Can use in rural areas and locations where there are no power lines- as solar water heaters do not need power from the utility grid you do not need to worry about having power lines at the locations you want to install your water heater. Installing new power lines can be very expensive.
- Can use even during power outages- as the solar water heaters do not rely on the grid power you can have hot water even during power outages.
- More environmentally friendly- production of utility grid power pollutes the environment in many ways. But by using solar-powered devices we can decrease environmental pollution as solar energy is clean energy.
- No operational cost- with solar water heaters you do not have to worry about any operational costs. Solar energy is free for everyone. But if you use a conventional water heater you have to pay for either fuel or electricity.
- The more safety-with solar water heater you do not have to worry about any electricity leakages as there are no wires that carrying electricity or power outlets near your shower. So solar water heaters provide more safety than conventional water heaters.
Disadvantages of using solar water heater;
- Need direct sunlight- solar water heaters need direct sunlight to operate effectively. Some solar water heaters can operate even under low light conditions. But the efficiency will be less. So they may not heat the water to too much higher temperatures.
- High initial cost- when compared to conventional water heaters, solar water heaters are expensive. You may find cheaper versions available in the market. But they are very low in quality most of the time. As there is no operational cost later, investing more money at the beginning is not a huge loss.
- Need extra roof space to fix solar collectors- as solar collectors need to be exposed to the sunlight, you have to fix them in a clear space without any shading. Most of the time rooftop is the best location for that. Unlike conventional heaters, you have to fix the solar collectors on the roof. So for that, you have to allocate space.
Why you should buy your solar water heater from a qualified manufacturer?
The main reason is, to work properly solar water heater has to be of high quality. If the materials or the structure are not up to standards, then the solar water heater will not work properly.
So always try to find qualified manufacturers when purchasing solar water heaters. Otherwise, your investment will go to waste.
How does a solar water heater work at night?
The storage tank for water heaters is very well insulated. So the heat will well capture inside the storage tank and keep the water temperature high. Even though there is no sunlight during nighttime, the heated water inside the tank will not drop its temperature much as the tank is insulated. So if you use water carefully during day time you can use the heated water during night time.
But if you are using water excessively then it is better to have either a storage tank with high capacity or a backup system. The backup system will heat the water for you during the nighttime.
Can you work your solar water heater during winter?
Yes, you can use a solar water heater during winter, as long as there is adequate sunlight. But sometimes solar water heaters can work even without sunlight as there is radiant energy from the sun present in the atmosphere.
But the efficiency will be less. So the maximum temperature that the water can reach is less. As the storage tank is well insulated, the low environmental temperature will not greatly affect this. Solar water heaters with flat-plate collectors and evacuated-tube collectors have good performance during the winter season and in snowy areas.
If you do not get sunlight for many days continuously it is better to have a backup system.
Is a solar water heater is a good investment for you?
The answer to this question depends on many factors such as usage, location, purpose, etc.
If you are living in a location where there is not much sunlight available throughout the year, it may not be a good investment for you. The main reason is the unavailability of adequate sunlight will prevent you from having the full advantage of your system.
Even though you are living in a sunny location, you have to make sure the sunlight is not obstructed by any means.
Then if we think about your usage, if you use hot water excessively then you have to go for a system with a large capacity. This system is not such a wise investment if you have to use the backup system continuously. As you have to pay an operational cost for your backup system.
Then the purpose of installing this system also can affect when deciding whether this is a good investment for you or not. If you are using this system just to decrease the power bills then you have to manage your water usage wisely. Also, to have a better idea you can calculate the amount of money you can save by using a solar water heater instead of a conventional water heater.
If you are living in a location with a high environmental temperature, this may not be a problem as there is not much time for cool off.
If you are just using this system as a step towards becoming off-grid, then this is one of the best options for you rather than using a conventional water heater that you have to power up by your home solar system.