Is a solar water heater cost-effective? Comparative Analysis

Solar water heaters are one of the most popular applications of solar collectors. Not surprisingly, a solar water heater can save up to 1500 units of electricity each day per 100 liters of water. Solar water heaters are undoubtedly the most eco-friendly option to heat water at home. But is it cost-effective for you? We can assume it can save money in the long run. But the initial investment, maintenance, and durability become essential factors when determining the overall cost efficiency.

Generally, the purchasing and installation cost of a solar water heating system is way higher than conventional water heaters. But think about loads of electricity bills you pay every month. For a solar water heater, you don’t have to pay for the electricity, which reduces your total electricity bill significantly. So, solar water heaters are cost-effective in the long run. Also, they are generally very durable and require the least maintenance.

Next, we’ll check the cost of solar heating systems in different regions.

Cost of a solar water heating system

A solar water heating system’s initial cost is a total of purchasing and installation costs. But this cost depends on many factors.

1. The main factor is whether your solar water heating system is active or passive. A passive water heater costs less than an active one. Passive heaters don’t have pumps to push water through the collectors. So naturally, you don’t have to pay extra for those parts. However, although passive ones are cheaper, they will struggle to provide hot water in overcast weather. They also lack a backup heating system. So overall, an active system will be a good option if you want a more efficient heating system.

2. The cost of a water heater also depends on the type of tanks and their sizes. So you have to pay more if you have more hot water requirements.

3. The cost may also vary depending on the type of collector base. Flat plate collector-based heaters are costlier than evacuated tube collector-based heaters.

In the United States

Generally, the price range of solar water heaters in the US is around $4000-$13000, while the average price is approximately $9000. Additionally, the installation cost may range from $1667 to $5402.

In India

In India, the price of a solar water heater starts from ₹15000, and it can go up to ₹99000. One significant advantage is most solar water heater companies in India offer a free installation service. But, free installation service can be limited to popular cities only.

In the United Kingdom

In the United Kingdom, the system plus installation cost varies from £3000 to £6000. 

Variables in cost-effectiveness

Geographical location

The cost of a solar water heating system can depend very much on your geographical location. Some countries and places receive plenty of sunlight throughout the year. At those locations, the system can make a huge saving. For example, consumers in tropical countries can reduce approximately 1000-1500 units of electricity (considering a 100 liter per day capacity system) using solar water heaters. They generally reduce up to 85% of electric utility bills. 

In contrast, northern EU, Canada, Australia, Newzealand, and South Africa don’t receive the same amount of sunlight throughout the year because of their location. So, in those places, solar water heaters are less cost-effective, and however, they can still save you money by reducing 50-70% of electricity bills for water heating purposes.

Weather and climate

Weather and climate greatly impact the cost-effectiveness of any solar device as they solely depend on direct sunlight. On a sunny morning of summer, it receives maximum sunlight. Also, summer days are longer than nights. So in summer, the device can receive sunlight for a longer time. So, they can reduce your electricity bill to a greater amount. You can make greater savings. But on a rainy or cloudy day, the amount of incident sunlight is less. On winter days, too, there is less sunlight in general. Also, winter days are shorter. On these less sunlight-receiving days, the solar electricity production rate goes down, and so does the savings. Now in some places, the rate and frequency of rainfall are higher. Clouds reduce the amount of sunlight.

Manufacturing cost

Solar water heaters consist of the following components.

• Solar collectors
• Heat transfer fluids
• Heat exchangers
• Storage tanks
• Pumps
• System controller

The cost mostly varies due to the first two components. 

Solar collectors convert sunlight into electricity. Evacuated tubes and flat plate solar collectors are the two most popular types. Evacuated tube collector-based heaters are the most costly and most efficient heaters. On the other hand, flat plate collector-based heaters are less efficient and cheaper. There are several other types of collectors of different efficiency and cost:

• Integral collector-storage type
• Unglazed flat plate collector type (collector made of rubber, whereas other flat plate collectors are made of glass or fiber)
• Air collector, etc.

Regarding the heat transfer fluid, water is the most feasible option. But in countries where the temperature lowers below the freezing point of water, you can’t use water as heat transfer fluid.

Fuel and energy prices in your region

Last but not least, the cost-effectiveness of solar water heaters also depends upon the fuel and other energy prices in your region. Some fuels are cheaper. For example, you may use wood and debris as fuel, and you may use fossil fuels. You may use other electric heaters to heat water. As solar water heaters need an initial investment, other ways may seem cheaper to go for. But you should never forget that it will be a one-time investment and a greener option. Anyway, if the energy price is higher in your region, you’ll save more by using a solar water heater.

Cost comparison of solar water heaters with electric and gas water heaters

Product cost

The cost of every water heater depends on the style and size. Still, I’m trying to show you an estimate for comparison. 

• An electric water heater costs around $1300- $2600. 
• Gas heaters are a bit expensive to purchase. A gas water heater’s price is around $950- $1500.
•  We discussed solar water heater prices earlier. They are much more expensive to purchase.

Installation cost

Installation cost also depends on the size of the storage tank.

• A 50-gallon tank electric water heater installation costs around $500. Its service life is 8-12 years. 
• A 50-gallon tank gas water heater installation costs around $700. Its service life is the same as an electric water heater. They both need power venting. It may add $600-$1100 to the installation cost.
•  In the case of solar water heaters, the installation cost is much higher than electric and gas heaters. For passive water, you have to pay $2000; for an active water heater, you may expect to pay around $3000. If you look at the service life, solar devices live longer than similar electric devices. Those water heaters serve at least 20 years.

Maintenance cost

An electric water heater will cost around $42/month on average, and a gas water heater will cost approximately $30/month on average. Solar water heaters are cheaper to maintain as they require less frequent repair and maintenance. You’ll need to clean tanks to eliminate sediments in all three cases.

In an electric water heater, you’ll need to check the well-being of the wiring and repair it if needed.

For gas heaters, you need to check for gas pipeline damages and repair, if any. In the case of solar heaters, you need to clean the panel as it is exposed to sunlight and so to rain, dust, and dirt.

Energy and fuel cost

This is something that makes a huge difference. You need to pay a monthly electricity bill for an electric water heater. The amount of the bill depends on the electricity rate in your area. Water heaters are a high power consumption device. Generally, they are available in 1-1.5kW. So, these heaters consume 30-45 units of electricity per month, considering they are being used for only an hour each day.

For gas water heaters, you must pay monthly bills for natural gas.

Now think about the energy you need to run a solar water heater! It converts sunlight into electricity. Thankfully sunlight is free of cost. That’s why one should go for a solar water heater. You don’t have to pay for energy or fuel.

Winner: Solar water heater

As you can see from the above estimate, solar water heaters are costly to purchase. The installation cost is also higher than the other heaters. But, a solar water heater is a one-time investment, just like any other solar device. Also, it is an environment-friendly and greener option. Many companies provide handsome discounts to spread awareness and make it popular. You can avail EMI facility too. And once it is installed, you don’t have to pay for the energy it needs to work. So you are going to save a lot of energy. Additionally, the maintenance is very low, and the service life is significantly higher than the other available options. Because of all these reasons, Solar water is the winner here when it comes to cost-effectiveness.

Cost of DIY solar water heater

Here I have another idea to reduce the burden of the initial investment. You may choose a DIY solar water heater and save the installation cost. You can find many stepwise guides on the internet. In this case, you have to do the components’ modeling, designing, and assembling all by yourself. You might have to spend around 400 USD for the whole task.

Conclusion

To conclude, I must say that a solar water heater, like any other solar device, is great for saving electricity. Not only that, they are an efficient, greener option among other available alternatives to go for. They are an excellent alternative to choose from if you want something durable. Once you manage to make the initial investment and the installation, you have nothing to worry about.