4 Best Solar Water Heaters

Sep 20, 2022 01:26 PM ET

Solar water heater is becoming popular nowadays. Whether you are exploring an additional off-grid source of power or looking to supplement the existing ones, water heater solar is becoming a component you won't want to miss. Nonetheless, using the sun to heat water is not new and is at least a decade-old tradition. With growing technology, these devices have been significantly evolved and refined to make them more capable of satisfying growing needs. Some of the improvements that have been made include solar absorption capacity, quality, and weatherproof properties.

What is a solar water heater?

It is a device that relies on sunlight for the production of energy used to heat water. The device has a solar collector placed on the roof of an apartment or building. The collector is then linked to a water tank. 

A solar power water heater can work in two ways depending on the type.

  • In the first method, unheated water flows from the tank and the collector and is heated.
  • In the second way, the water is heated via high-capacity fluid warmed in the collector. The fluid moves the heat via tubes, warming the tank water.

Benefits of using solar water heaters

Solar water heaters are important home-use devices. If you are in a location with a lot of solar energy, you will likely see reduced energy spending. Below are some gains you get with solar powered water.

Reduced carbon footprint

Stainless steel compact solar hot water heater uses carbon-free solar energy to warm water that can be used domestically. By taking advantage of solar water heaters, you help keep the environment clean by tackling bad gases.

Access to freely-available energy

Solar is an off-the-grid energy source. That saves on the usual energy bills.

High reliability

Well-maintained solar water heaters can give a service of up to 25 years. When in an area of sufficient solar, you are guaranteed a reliable and consistent energy supply.

Lower costs compared to solar PV panels

Do you know that fewer solar water heaters are required than traditional solar PV panels? That allows a lower initial cost and less roof space. Besides, cheap solar water heater equipment carries a simple technology. That makes them more affordable than advanced solar systems and helps you save huge amounts of money

Easy to mount

Passive solar water heater is one of the simplest to install. Little or no plumbing know-how is needed. With the passive systems, the management is also simple since no wiring or pumps are required. Very limited hardware is also purchased.

Little maintenance needed

There are no moving parts. As a result, there is no tear, wear, and breakages that would raise the costs of maintenance. Besides, care only involves cleaning the tubes to remove any dirt. That assures low prices of keeping the equipment.

What to consider when choosing the best solar water heaters?

Solar water heaters have distinct characteristics. The best solar water heater can be chosen based on:

Type

Solar hot water heater systems are different on the collector and circulation systems. 

Batch collectors

Integrated Collector Storage systems or simply Batch collectors are used in dark-colored storages. They do not work well in cold climates.

Flat-plate collectors

Flat-plate collectors come with a metal casing and flow tubes. They also have an absorber plate. The absorber's role is transferring solar energy to the water flowing via the tubes.

Evacuated tube collectors

The third, evacuated tube collectors, feature a metal/glass tube. The tube contains the water, while on the outside is a larger glass tube that creates a vacuum for heat retention. Evacuated tube collectors are very effective in low temperatures of up to minus 40°C.

Regarding circulation, there can be passive or active, direct, and indirect systems. 

Passive systems

In the passive class, no pumps are involved, and water from the collectors moves by natural forces. The water heaters can be easily maintained and are sold at a lower cost.

Active systems

In an active system, water is moved by electrified pumps and controllers. Active systems are more costly due to equipment needs. The systems need expertise and are also difficult to maintain.

Direct systems

A direct system moves water via the collectors.

Indirect systems

An indirect system allows the solar heat to move via a non-freezing liquid. 

Capacity

What are the water requirements? The selected solar water heaters should be able to warm water that meets the domestic or commercial demands. The capacity is normally given in Liters Per Day. A capacity of 500 liters per day would be the starting point for commercial uses. The capacity can be increased depending on the level of water usage.

Size

Size matters for solar water heaters. The collector area is an important consideration. A 20-square feet collector area would be sufficient for a family of about 2. 

Besides, a small 50-60 gallons storage tank would be ideal for 1-3 people, which can be increased to 80 gallons or up to 4 people. The rule of thumb is that the storage tank capacity relates to the collector.

Service life

In most cases, the service life of solar water heaters will reflect the care taken on them, the environment, quality, and installation. They can last between 10-25 years before you replace them. The ideal solar water heater has a defined lifespan and carries a warranty for a specified period. To ensure that your solar water heater lasts a while, follow the following key steps:

  1. Check them regularly for any defects
  2. Clean the solar panels and the exterior of its tank on a regular basis with mild soap and water
  3. Annually flush out the sediments in the tank.
  4. Descale the solar water heater every few years to eliminate tough deposits accumulating in the tank

Temperature regulation

Select solar water heaters that keep water temperatures in check. Those with thermostatic features allow temperature control to a required threshold which prevents scalding effects. Normally a temperature range of 60-70 degrees Celsius would be preferable.

Water pressure system

Water pressure is a key ingredient since it affects the operation of the heating apparatus. The correct system keeps a pressure equilibrium between the system and the water supply line. Also, consider the installation area, whether a flat or pitched roof, as this will determine the type of system to use.

User reviews

Solar power water heater users can give important insights that can guide your purchasing decision. Positive reviews indicate an efficient and quality system that you need to consider. Also, evaluate other key aspects and judge a product comprehensively rather than solely relying on user reviews.

Do solar water heaters work in winter?

Yes. They work in winter since they have efficient insulation with radiator fluid features. In winter, diffusion radiation heats the water, ensuring an uninterrupted flow of warm water. 

Can solar water heater generate electricity?

Solar water heaters do not produce electricity. That's because they use sunlight to generate heat rather than energy. 

How much money can be saved with a solar water heater?

Savings on solar water heaters vary. However, estimates of energy savings due to solar water heaters' usage can go up to upwards of 50%.

How much does a solar water heater cost?

Residential solar water heaters cost between $3,000-$9,000. For passive devices, the average price is $1,000. The cost excludes potential federal tax credits. The expenses of the unit and installation may vary.

6 Best solar water heaters 

Duda Solar 180 Liter Standard Passive Water Heater

Duda Solar 180 Liter Standard Passive Water Heater

Specifications 

  • Capacity: 180 liters 
  • Material: Galvanized or painted
  • Tank diameter: 460mm or 18.1 inches
  • Internal tank material: Food-grade stainless steel 
  • 58mm by 1800mm vacuum tubes 
  • High boron silicon 3.3 glass 

Reasons to buy

  • Duda solar heater has a high energy absorption effectiveness of up to 96%.
  • The heater takes a few minutes to have the water warm up, even when the weather is unfavorable.  
  • Stainless steel is ideal in areas where the water may be salty, preventing rusting. 
  • Duda solar heater is easy to install, and it does not require any complex tools. 
  • The solar heater is made from durable material, and does not need constant replacement of parts. 

Reasons to avoid 

  • Performance largely depends on weather patterns, with minimal output during winter. 
  • The heather is cumbersome in weight and size when moving around. 
  • It is relatively slow in comparison to the conventional electrical powered water heaters. 

Features 

The heater is solar-powered and has an internal battery

Has an attached water tank for direct heating of portable water 

The heating unit has an electric backup water heating a TK-7Y controller

The tank’s hot water outlet links directly to your home water tap. 

Check price Duda Solar Heater

SunRain Solar Vacuum Tube Collector- 20 Tube Solar Water Heater

SunRain Solar Vacuum Tube Collector- 20 Tube Solar Water Heater

Specifications: 

  • Weight: 250 pounds or 113 kgs 
  • Number of tubes: 20
  • Warranty period: 5 years 
  • Material: Aluminum, copper

Reasons to buy: 

  • It is the most powerful solar heater that is made for durability and effectiveness. 
  • Made of layers that have a strong heat conducting capacity and are extra-durable.
  • More efficient collector with twice as large collector compared to other available solar heaters. 
  • It is the most effective solar unit in maximizing energy from the sun, even on less sunny days. 
  • The solar heater is easy to install with no complex plumbing skills required. 

Reasons to avoid:

  • SunRain solar heater is relatively slow and may take longer to charge.
  • The unit is bulky and less portable. 
  • It has a short manufacturer’s warranty period. 

Features:

  • SunRain is fitted with a vacuum tube and enhanced heat pipe technology
  • The inner tube lining is made of food-grade aluminum nitrogen coating, an absorbing coating material.
  • The film coating 3Hi’’ vacuum tubes apply a three-system for maximum energy absorption. 
  • The water heater has multiple roof mounting options. 

Check price SunRain Solar Heater

Sportneer Solar Heating Portable Shower Bag

Sportneer Solar Heating Portable Shower Bag

Specifications:

  • Measurements: 11.8 x 5.9 x 2.8 inches
  • Weight: 1.2 pounds or 0.54 kgs
  • Colour: army green
  • Material: PVC
  • Capacity: 5 gallon/20L

Reasons to buy:

  • A large water capacity makes the solar water heater suitable for high demands
  • Good for frequent travelers and camping lovers. The water heater is the right one to ensure you get hot water anytime. The device can heat water quickly and is highly portable
  • Value for money due to the quality offered
  • Very light weight which makes installation and carrying easy

Reasons to avoid:

  • Water temperature of not more than 50 degrees Celsius

Features

  • The device heats water for up to 45 degrees Celsius in only 3 hours. That guarantees you quick access to warm or hot water whenever needed.
  • Sportneer consists of a durable and tough PVC material. That allows it to have high resistance and enhances quick heating. 
  • With a capacity of 5 gallons or 20 liters, Sportneer is the right solar water heater when the water demands are high. 
  • Sportneer features an upgraded version. The new version has a convenient switch control for opening and closing to control the flow of water. Similarly, a longer hose allows a very flexible valve that is leak-free. 

Check price Sportneer Solar Heating Bag

SunQuest Solar Pool Heater Panels

SunQuest Solar Pool Heater Panels

Specifications:

  • Measurements: 30.04 x 13.58 x 13.39 inches
  • Weights: 28.7 pounds
  • Roof-mounted

Reasons to buy:

  • With SunQuest, you get equipment with a guaranteed value due to its premium quality
  • Enjoy limitless time swimming by heating the pool as and when you like
  • No limitation on where to place the heater allowing versatility in use
  • Heats water heavenly 

Reasons to avoid:

  • You need to buy a separate system kit
  • A little bit heavy equipment

Features

  • SunQuest solar water heaters carry superior technology. The device is best rated on performance and durability.
  • SunQuest is more versatile than the electric or gas heater. Users can buy what they need that fits their requirements. They can place devices on the roof, ground, or rack. Customization allows the user to make the equipment fit for the intended task. 
  • A pool solar water heater can raise the water temperatures to 10 ℉. That allows you to keep the pool water warm for extended swimming. To generate more reassuring results, users can cover the heat with a Liquid Solar Blanket. 
  • The solar water heaters have 2" OD headers that guarantee optimal water circulation. It also ensures maximum flow, with less back pressure for the filter and pump.

Check price SunQuest Solar Pool Heater Panels

Duda Solar Water Heater

Duda Solar Water Heater

Specifications:

  • Weight: 211 pounds
  • Size: 15, 20, 25, 30 Tube
  • Vacuum rating: not more than 5.0 x 10^3 Pa
  • Manifold insulation 45mm 93 Kg/m^3 Rockwool
  • 87psi Max Operating Pressure
  • 5.25 gpm Max Flow Rate

Reasons to buy:

  • Best when looking for a solar water heater that can work in lower solar energy. It also keeps the energy longer, ensuring you have a regular power supply
  • Cut costs as the equipment qualifies for a 30% Federal Tax rebate
  • Good when relying on hard water that is causing blockages and corrosion to existing water systems. 

Reasons to avoid:

  • It needs some electrical wiring and plumbing skills to install
  • Costlier compared to other solar water heaters

Features

  • Duda solar absorbs 93%-96% of solar. It is also rated the best in heat retention to keep you using it longer.
  • It comes with a 200-liter water split system. That allows it to do well with hard water.
  • Duda has 20 energy-efficient vacuum tubes, a stainless-steel water tank, and a submersible water pump that ensures a complete setup for your hot water needs.
  • Winter resistance keeps the equipment in good working condition.

Check price Duda Solar Heater

GAME SolarPRO Curve Solar Pool Heater

GAME SolarPRO Curve Solar Pool Heater

Specifications:

  • Measurements: 27.56 x 5.91 x 4.88 inches
  • Weight: 18.3 pounds

Reasons to buy:

  • It can be used for different types of water pools, including an outdoor application.
  • Room for adjustment, which increases ease of use
  • It is solar-powered and allows you to be eco-friendly.
  • Very innovative design makes it maintain the aesthetics of the installed space.

Reasons to avoid:

  • Not a quick pool solar water heater since it is intended to heat the water gradually. 
  • Comes with some technicalities in installation and may require plumbing skills

Features

  • The solar water heater is made of high-quality materials to withstand harsh exposure to outdoor elements. 
  • The solar water heater for pool is made to stand above-ground and is suitable even for inground pools. The heater can raise the pool temperatures by 5 degrees in four days for an 8,000-gallon pool. 
  • The GAME solar has an innovative curved shape to maximize its heat absorption. There are threaded ports for versatility in installation. 
  • The solar water heater has adjustable legs. It is thus compatible with Bestways, Intex, and above-the-ground and inground water pools. The adjustable stands are also foldable and allow the user to set the maximum exposure to solar energy.
  • The GAME solar has a clear cover whose role is to retain heat.

Check price GAME SolarPRO Pool Heater

Is solar powered water heater worth the money?

Solar powered water heater is worth the money. While solar water heater cost can be huge, you will slowly recoup the investment by saving on the monthly utility bills. However, the water solar heater price should not be a deterrent. After the payback period, you are guaranteed almost free water heating for the rest of the system's lifespan. Coupled with limited maintenance costs, you will enjoy a lifetime of savings that would be accrued for conventional water heaters.

Besides, some solar water heaters come with federal tax credits. These tax credits lower the initial investment in the system and make them affordable. Comparatively, you will not enjoy the tax credits by remaining on the electricity grid, which is more expensive in the long run.

When going off-grid, solar water heaters will also offer a great option to electricity. You won't have to rely on costly and harmful generator power.

There are indirect benefits too. By contributing towards the reduction of global warming through tapping into solar energy, you protect future generations and ecosystems. In the process, you get a clean source of energy that keeps you healthy.  

Summary

Still finding it hard to select the best solar powered water heater? You need not worry. Our list is not wholly exhaustive but offers great starting options. What you need to do is check the one that perfectly matches your needs and comes within your preferred budget. You could also check those that carry federal tax credits to save on upfront costs.

Our selections tick all the boxes in terms of quality, features, and specifications. If you are a regular traveler, Sportneer Solar Heating Portable Shower Bag would be suited best. The selection is yours, and it is a no-brainer that any solar water heater system you settle on will be a step toward being eco-friendly. In the end, you get hot water that will lower your monthly utility bills by 50%. 



SOLAR DIRECTORY
Solar Installers, Manufacturers