Solar Water Heating (Everything You Need To Know)

A deep dive (with cost analyses)

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Solar water heating is a new high-tech solution to bringing renewable energy straight to your home. More specifically, straight to your water heater.

Having a solar heater comes with many benefits. From substantial savings on energy to reduce your carbon footprint, you’ll find a plethora of advantages surrounding solar water heaters.

So, what are solar water heaters? Are there different types? How does a solar water heater work? These are all great questions. If you’re considering adopting solar energy into your life and want to make use of a solar water heater, these are going to be necessary to answer.

With this in mind, this article is meant to provide you with everything you need to know about solar water heating. Keep reading to learn the ins and outs of solar water heating.

What Are Solar Water Heaters?

Solar water heaters typically come in the form of a solar collector located on the roof of the building you intend to use it with. Normally these are solar panel-shaped.

Once the solar collector has amassed heat, it’s then passed to your water tank via a circulating pump. It’s helped by a thermal regulator that will regulate the temperature of your water heater to optimize energy and safety. Once the collector is bringing in heat above the level of the water in the tank, the regulator will cease working to restrain itself from needlessly using energy. This entire process is designed to ensure that using solar water collectors and heaters is as cost-effective and environmentally friendly as possible.

Types of Solar Water Heaters

In general, there are two types of solar water heating systems:

  • Active Solar Water Heating Systems
  • Passive Solar Water Heating Systems

Active solar water heating systems work by incorporating circulating pumps and controls to actively heat your water tank throughout the day.

Passive solar water heating systems don’t use these tools and work by passively absorbing heat and sunlight throughout the day.

So, how does a solar water heater work?

Active Solar Water Heating Systems

Active solar water heating systems are ideal for those who want to ensure they constantly have heated water throughout the day and year. There are two types of active solar water heating systems:

  • Direct circulation systems
  • Indirect circulation systems

Direct circulation systems are designed to circulate household water through the collectors on the top of your roof. As the water passes through these solar power collectors, they’ll be heated to the appropriate temperature. This will keep your water at a heated temperature throughout the day as the water will continue to circulate through the collector.

Indirect circulation systems are designed to circulate a heat-transfer fluid through collectors. These are designed to be non-freezing so you won’t have to worry about your circulation system when the temperature drops below freezing. Once the heat-transfer fluid runs through the collectors, they’ll go into a heat exchanger. After the exchange occurs, the heating of water will be completed and the water will then flow into the household.

The main difference between these two systems is the conditions they’re designed to be used in.

Direct circulation systems are meant to be used in places where it rarely freezes. These hotter climates will benefit the most because the circulation is continuous and you’ll gain more from the constant heat. On the other hand, indirect circulation systems are great for places where it’ll freeze sometimes, or constantly, throughout the year. By using a heat-transfer fluid that won’t freeze, you won’t ever have to worry about your system failing at certain times of the year.

Passive Solar Water Heating Systems

Passive solar water heating systems won’t use the fancy tools and features that active solar water heating systems do. This means that they’re typically less efficient. However, they’re much less expensive as well.

The real benefit comes from the robust reliability and durability of passive solar water heating systems. Because you won’t have to worry about as many mechanical failures, the inherent nature of passive solar water heating systems will make them lost longer and be more reliable.

There are two basic types of passive solar water heating systems:

  • Thermosyphon systems
  • Integral collector-storage passive systems

Thermosyphon Systems

Thermosyphon systems work by having water flow through the system. Cool water will sinks to the bottom of the system while warm water rises to the top.

Because the warm water rises to the top, this type of system will need to be installed below the water storage tank enable the warm water to rise into the tank. These are incredibly effective systems that are known to be more reliable than the integral collector-storage passive systems.

However, the heavy storage tank will mean that whoever is installing the system will need to be extremely careful regarding the roof design. This extra expertise required during the installation combined with the heavier storage tank means that these kinds of systems are typically more expensive than the integral collector-storage passive system.

While the investment may be larger, they’re a popular solution for having a reliable water heating system throughout the year. Ideally, you should be looking to use the building that you install this water heating system in to be in use long term. The extra initial cost at first will take a while to receive a return on investment, but you can reliably count on it to save you money for years to come.

Integral Collector-Storage Passive Systems

Integral collector-storage passive systems are designed to be used in places where the climate rarely freezes. Similarly to the active systems, this type of passive system will use collectors that absorb heat. They’ll reside on top of your roof.

While you won’t have water actively circulating through the collectors, you will be able to passively heat your water tank as the collectors transfer the heat directly. It’s not as efficient as active systems, but you can count on it to run longer without issues.

This will not only save you more money in the long term but you’ll also save more money on the reduction in repairs. Less mechanical parts will mean less time spent fixing them when they inevitably need work done.

Solar Water Heaters vs Photovoltaic

The great debate in the solar power industry is solar them water heaters vs photovoltaic technology. Both are solutions to collecting solar energy and converting it into electricity. The main difference between the two is how they work.

Solar Photovoltaic

Photovoltaic energy is creating by the implementation o the photovoltaic effect. In this effect, a photo meshes with a panel created of semiconductors. Upon impact, the photon releases electrons and generates electricity by utilizing the energy created when the electrons are exposed to light.

Typically, this type of solar power is used mainly for generating electricity for household uses. It’s not commonly associated with heating water tanks, but it can be an effective solution under the right conditions.

Solar Thermal

Solar thermal energy is created by having water or other fluids circulate within tubes that pass through solar collectors. This can occur with either active or passive solar water heating systems. In either of the systems, the water flows through these collectors and become heated in the process.

Because this type of solar energy requires constant sunlight, you’ll often find that households use a backup boiler to provide year-round heat and hot water when the seasons change into the colder months.

The Advantages of Solar Water Heaters

Solar water heaters and heating systems come with a large variety of advantages. From saving money to providing a better environment for the world to enjoy, you won’t find a shortlist anywhere on the web.

Here are the advantages you could expect:

  • Reduce your electricity or gas bill by using free and renewable energy
  • Solar thermal collectors will take up less space than photovoltaic panels
  • It’s an efficient solution to generating heat
  • It’ll decrease your carbon footprint
  • Both residential and commercial properties are eligible to claim the Federal Solar Tax Credit by the government. This tax break effectively means you’ll be getting paid for generating your heat. Lower bills, better for the environment, and getting paid by the man? It’s a win-win.

Reducing Your Bills

Heating water is, by far, one of the most expensive things to pay for as far as utilities are concerned. This is because water takes so much energy to heat. It’s estimated that about 18 percent of domestic energy is used just to heat water in any given household.

Regardless if you use electricity or gas to heat your water, you’re looking at great savings year-round by using solar water heaters.

Although, it should be noted that the initial cost of investing in a solar water heating system can be significant. Be sure that you’re going to be using the property you’re installing it in for a long while to get your financial returns.

Take Up Less Space On Your Roof

Size-wise, solar thermal panels are much more efficient than photovoltaic panels. Photovoltaic panels may require as many 16 panels to be able to generate the same amount of power as two to three solar thermal panels.

If you’re interested in putting up solar collectors and space is limited on the roof, you’re going to want to be using solar thermal panels rather than photovoltaic panels.

The Federal Solar Tax Credit

The Federal Solar Tax Credit is offered by the U.S government as a way to incentive both residential and commercial properties to lean toward using renewable energy.

Those who install a solar system in either type of property will be eligible to claim 26 percent of the total project costs as a credit on your federal tax return. These total project costs include installation, permits, and equipment required.

Tax credits work by giving you money back on your income tax you owe. One dollar worth of tax credit means you’ll be paying one dollar less in taxes. This means that every dollar you spend is effectively free money. At least 26 percent of the total cost is, anyway.

This means if you invest $20,000 into your solar water heating system, you’ll owe $5,200 less in taxes the following year. If you typically plan your taxes to receive a moderate return each year, you’ll be pleasantly surprised with an extra $5,200 in your pocket.

It should be noted that this tax credit isn’t going to last forever. It’ll last through 2022, but it may not be available afterward. This means right now is a great time to invest in solar power and solar water heating.

Solar Water Heater Costs

Honestly, $20,000 is a bit of an exaggeration when it comes to solar water heater costs. Yes, you can spend that much. And, yes, it will likely be worth in the long term. However, most solar water heater costs won’t run you nearly that much.

The amount you’ll be paying will generally be dependent on which type of system you’ll be installing into your property. There are also several outlier factors you should take into consideration.

The Cost of Active Systems

Generally, you can expect to pay between $2,000 and $4,000 for an active water system.

This money will go to providing you with a solar collector and a storage area for the heat. The storage area needs to be large enough to house all the water you need to be heated, so ensure you’re taking the amount of water you need to be heated at any given time into account.

It can also be a good idea to consider adding an electric/gas back up system to heat your water in the case that your solar water heating system ever fails. It can also kick in when the weather is cold or too cloudy to produce any meaningful amount of heat.

The Cost of Passive Systems

If you’re looking to go with Mr. Reliable, a passive system to heat your water will run you between $1,000 and $3,000 depending on how much water you’d like to store. Typically, you’ll want to use this type of system if you’re purchasing for a residential property.

If you go with a Thermosyphone system, you can expect to pay on the upper end of the scale while Integral Collector-storage Systems will be priced on the lower end of the spectrum.

Finding out which one is most cost-effective for you will depend on your needs and what type of property you’ll be wanting to use your solar heating system with.

Are Solar Water Heaters Worth It?

So, in the end, are solar water heaters worth it? The answer is: absolutely. They’re a great way to save money on your bills, reduce your carbon footprint, and can be an effective solution to making that happen. When compared to the competition found in photovoltaic technology, they’ll often come out ahead.

However, you should be aware that solar water heaters will only be worth if you’ll be using the property in the long term. You won’t save any money on bills with a solar water heating system that you immediately sell-off. However, solar water heating systems can increase the overall worth of your property. You simply won’t see as stark of a return on your investment if you don’t take the benefits of having reduced bills.

Other things that could impact the amount you save when you invest in a solar water heating system include:

  • The geographic location of your property
  • The structure of your property
  • The weather and climate of where you live
  • The need for repairs and general maintenance

Geographic Location of Your Property

The amount of heat that your solar collectors can collect reflects mainly on the amount of sunlight that they’re exposed to throughout the day. While they will be passively able to absorb some heat during cloudy days, the vast majority of your heat will come when the sun is shining.

Solar power water heating systems will be most effective in locations with abundant sunshine and places where the climate isn’t cold. This doesn’t mean that the climate can’t be cold ever, there simply needs to be seasons where the sunshine and heat is abundant throughout the day.

For example, solar heating systems are popular throughout the northeast U.S. This may seem counterintuitive at first, given that states such as Maine and New York typically receive harsh winters, but the amount of sunshine they receive during the summer months make solar power a viable option there.

The Structure of the Property

When considering whether solar power is right for you or not, take into consideration how your property is built. Ideally, you want most of your roof to pointing toward the south.

This is because the south-facing side of your roof will receive the most direct sunlight throughout the day. If even one of the solar cells in your solar collectors become covered by clouds or shade, it can reduce the overall power generated by your solar power system by up to 50 percent.

Because of this, you’ll want to ensure that your roof doesn’t have anything shading it and that as much of the roof is facing south as possible to receive the most benefit from the sun.

Weather and Climate

The weather and climate of where your property is located are going to be incredibly important when trying to figure out if solar water heaters are worth it for you.

Solar power is typically thought of in southwest states such as southern California and Arizona. While these are great spots for solar power because of the abundance of sunshine and good year-round weather, other spots may be appropriate as well.

States in the northeast and the southeast U.S will be able to get a lot of use from solar power, as can some areas within the Midwest. This is because these areas will receive a lot of sunshine at certain times of the year. While winters may be harsh in the Midwest and Northeast, they’ll be able to gain returns on their solar water heating investment during the Spring and Summer months.

Those in states such as Oregon and Washington may still find benefits in solar power. However, the return on investment for those in these types of states will take longer to receive. The constant clouds and rain will inhibit your solar power systems from being able to produce optimal energy and heat.

In Summary

By now, you should be an expert on everything you need to know about solar water heating and solar water heating systems.

There are several different systems and deciding which one is best for you will depend on several factors that were discussed above.

Remember to always take into consideration the geographical location and how your property is oriented when deciding if solar power and solar heating systems are right for you.

In the end, solar water heating systems are an effective way to provide heat to your water while reducing bills, helping the environment, increasing the value of your property, and it will even earn you free money from the government if you act fast enough.

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