What Is a Solar Water Heater?
A solar water heater is a device that harnesses the power of the sun to heat water for domestic, commercial, or industrial use. It is an eco-friendly and cost-effective alternative to traditional water heaters that rely on electricity or gas.
The basic components of a solar water heating system include solar collectors, a storage tank, a heat exchanger, and a control system. Solar collectors are the devices that absorb sunlight and convert it into heat energy. There are two main types of solar collectors: flat-plate collectors and evacuated tube collectors. Flat-plate collectors are the most common type and are made up of a flat, rectangular box with a dark absorber plate and a transparent cover. Evacuated tube collectors, on the other hand, are made up of a series of glass tubes containing a vacuum that provides insulation and reduces heat loss.
The storage tank stores the heated water until it is needed. There are two main types of storage tanks: integral collector-storage (ICS) tanks and conventional tanks. ICS tanks are used in passive systems and are integrated with the solar collector, while conventional tanks are used in active systems and are separate from the solar collector.
The heat exchanger transfers the heat from the solar collector to the water that is stored in the tank. There are two main types of heat exchangers: direct circulating systems and indirect circulating systems. Direct circulating systems circulate the water through the solar collector and the storage tank, while indirect circulating systems use a heat transfer fluid to transfer the heat from the solar collector to the water in the storage tank.
There are two main types of solar water heating systems: passive systems and active systems. Passive systems rely on natural convection to circulate the water, while active systems use pumps to circulate the water. There are also two main types of passive systems: thermosyphon systems and integral collector-storage passive systems. Thermosyphon systems rely on natural convection to circulate the water, while integral collector-storage passive systems use the ICS tank to store the heated water.
How Does a Solar Water Heater Work?
A solar water heater is a renewable energy system that uses the sun’s energy to heat water for various applications. Solar water heating systems are typically classified into two main types: active and passive systems.
Active Solar Water Heaters
Active solar water heaters have a circulating pump that moves the heat-transfer fluid or non-freezing heat-transfer fluid from the collector to a storage tank. These systems are further classified into two types: direct and indirect systems.
- Direct systems: In a direct system, the heat-transfer fluid circulates through the collector and then directly into the storage tank. These systems are suitable for areas where freezing temperatures are not a concern.
- Indirect systems: In an indirect system, the heat-transfer fluid circulates through the collector and then through a heat exchanger into the storage tank. These systems are suitable for areas where freezing temperatures are a concern.
Passive Solar Water Heaters
Passive solar water heaters do not have a circulating pump and rely on natural convection to circulate the heat-transfer fluid. These systems are further classified into two types: direct circulating system and indirect circulating system.
- Direct circulating system: In a direct circulating system, the heat-transfer fluid circulates through the collector and then directly into the storage tank. These systems are suitable for areas where freezing temperatures are not a concern.
- Indirect circulating system: In an indirect circulating system, the heat-transfer fluid circulates through the collector and then through a heat exchanger into the storage tank. These systems are suitable for areas where freezing temperatures are a concern.
Heat Pump Water Heaters
Heat pump water heaters are another type of solar water heating system that uses electricity to move heat from the air or ground to heat the water. These systems are highly efficient and can save energy and money on utility bills.
Solar water heaters work by using the sun’s energy to heat the water in the collector. The collector absorbs the sun’s energy and transfers it to the heat-transfer fluid or non-freezing heat-transfer fluid, which then circulates through the system to heat the water in the storage tank. The storage tank is insulated to minimize heat loss and keep the water hot until it is used.
Overall, solar water heaters are a cost-effective and environmentally friendly way to generate hot water for various applications. They can be used in any climate, and the fuel they use – sunshine – is free.
Advantages of Installing a Solar Water Heater
Switching to a solar water heater has several advantages. Here are some of the benefits of installing a solar water heater:
Cost Savings
One of the primary advantages of a solar water heater is the cost savings. Solar water heaters are cost-effective and can save homeowners a significant amount of money in the long run. According to the Department of Energy, a solar water heater can provide up to 50% savings on water heating costs compared to traditional water heaters that use electricity or gas.
Energy Efficiency
Solar water heaters are energy-efficient and use renewable energy from the sun to heat water. This makes them an eco-friendly alternative to traditional water heaters that rely on fossil fuels. By reducing the amount of energy needed to heat water, solar water heaters can help reduce overall energy costs and utility bills.
Low Maintenance
Solar water heaters require very little maintenance compared to traditional water heaters. They have fewer moving parts and do not require electricity or gas to operate. This means that homeowners can save money on maintenance costs over time.
Rebates and Incentives
The Department of Energy offers rebates and incentives for homeowners who install solar water heaters. These incentives can help offset the cost of a solar water heater and make it more affordable for homeowners.
Backup System
Solar water heaters typically come with a backup system that ensures hot water is always available, even during periods of low sunlight. This backup system can be a gas or electric water heater that kicks in when the solar panels are not producing enough energy to heat the water.
Long Payback Period
While the initial cost of a solar water heater may be higher than a traditional water heater, the cost savings over time can make up for the difference. The payback period for a solar water heater is typically around 4-8 years, depending on the cost of electricity in the area.
Overall, installing a solar water heater has several advantages, including cost savings, energy efficiency, low maintenance, rebates and incentives, a backup system, and a long payback period. It is a great investment for homeowners who want to reduce their energy costs and carbon footprint.
Tips for Buying a Solar Water Heater
When selecting a solar water heater, there are several factors to consider. The following tips can help you make an informed decision:
System Size
The size of the solar water heater you need depends on the hot water demand of your household. A professional installer can help you determine the appropriate system size for your needs.
Energy Star and Federal Solar Tax Credit
Look for Energy Star-certified solar water heaters, which meet strict energy efficiency guidelines. Additionally, you may be eligible for a federal solar tax credit, which can help offset the cost of installation.
Hot Water Costs
Consider the cost of heating water with your current system versus a solar water heater. In many cases, a solar water heater can save you money on your monthly utility bills.
Professional Installation
It is recommended to have a professional installer handle the installation of your solar water heater. This ensures that the system is installed correctly and safely.
Repair
Make sure to choose a solar water heater with a warranty and reliable customer support. This can help minimize repair costs and downtime.
Frequently Asked Questions
Before purchasing a solar water heater, it is important to have all your questions answered. Some common questions include:
- How does a solar water heater work?
- Can a solar water heater provide enough hot water for bathing and laundry?
- Will a solar water heater work in all climates?
- How does a solar water heater affect plumbing and other home systems?
Photovoltaic (PV) System
If you already have a photovoltaic (PV) system installed, consider pairing it with a solar water heater for even greater energy savings.
By considering these factors and doing your research, you can select a solar water heater that meets your household’s hot water needs while also helping you save money and reduce your environmental impact.
3 Best Solar Water Heaters in Malaysia
Aqua Solar L66 (300 Liters)
The Aqua Solar L66 is a solar water heater that has a capacity of 300 liters or 66 gallons. It is a part of the Lite & Easy series by Aqua Solar Technology. Here is a short summary of the Aqua Solar L66:
Pros:
- High-temperature mid-efficiency
- Qualified installation
- 304 grade stainless steel (1.2mm thickness)
- Pressureized system
- 10 riser tubes for each panel (Higher Efficiency)
- 1-year guarantee + 9-year warranty
- 100% full set anti-rusted material
- Relief valve setting 850kPa (Higher Pressure)
- Backup heater
- Outer casing – Stucco Aluminium
Cons:
- None found
Specifications:
- Capacity: 300 Liters / 66 Gallons
- Dimension: L2438mm x W1830mm x H584mm
- Overall Weight (Empty): 93kg
- Overall Weight (Full): 398kg
- Storage Tank Cylinder Material: Marine Grade Stainless Steel
- Outlet Cylinder Case Material: Aluminium Stucco
- Insulation Material: 50mm High Density
Aqua Solar L66 is a great choice for those who want a reliable and efficient solar water heater. It is made of high-quality materials, has a pressureized system, and comes with a 1-year guarantee and a 9-year warranty.
Solarmate SM 300-C Solar Water Heater
The Solarmate SM 300-C Solar Water Heater is a reliable and efficient system that can provide hot water for your home or business. It is designed to be environmentally friendly and energy-saving, making it an excellent choice for those who want to reduce their carbon footprint.
Pros:
- The system is made of AISI standard stainless steel with a thickness of 1.2 mm, which makes it durable and long-lasting.
- The low iron tempered glass solar panels ensure that the system can withstand high pressure.
- The system comes with a 10-year warranty, which gives you peace of mind knowing that you are protected against any defects or malfunctions.
- The backup heater ensures that you have hot water even when there is no sunlight.
Cons:
- The initial cost of installation can be high, which may not be feasible for everyone.
- The system may not be suitable for areas with limited sunlight.
Specifications:
- Capacity: 300 liters
- Material: AISI standard stainless steel (1.2mm thickness)
- Solar Panels: Tempered Glass
- Pressure: 850kPa
- Warranty: 10 years
Solarmate SM 300-C Solar Water Heater is a durable and efficient system that is environmentally friendly and energy-saving. It comes with a 10-year warranty and a backup heater to ensure that you always have hot water. However, the initial cost of installation can be high, and it may not be suitable for areas with limited sunlight.
Summer CX300 Solar Water Heater | 300 Liters
The Summer CX300 Solar Water Heater is a high-quality solar water heater that can provide hot water for every home and family. It is designed to be energy-efficient and eco-friendly, making it an excellent choice for those who want to reduce their carbon footprint.
Pros:
- High-quality solar water heater that can provide hot water for every home and family
- Energy-efficient and eco-friendly design
- Comes with a rain shower set for easy cleaning and maintenance of the temperature of the water flow
- Solar water pump system full set included
- 10-year warranty for tank and panel leaking
Cons:
- The initial cost can be high compared to traditional water heaters
- Requires sufficient sunlight to operate efficiently
Specifications:
- Capacity: 300 liters
- Type: Solar water heater
- Material: Stainless steel
- Warranty: 10 years for tank and panel leaking
- Dimensions: 191 cm x 67 cm x 56 cm
Summer CX300 Solar Water Heater is an excellent choice for those who want an energy-efficient and eco-friendly solution for their hot water needs. With its high-quality design and 10-year warranty, it is a reliable option that can provide hot water for every home and family. The rain shower set and solar water pump system full set make it easy to clean and maintain the temperature of the water flow. While the initial cost can be high compared to traditional water heaters, the long-term savings on energy bills make it a worthwhile investment.
