The use of solar panels as alternatives to traditional fossil fuels is getting more prevalent every day. When you look at solar PV vs. solar thermal panels, you’ll find that they serve the same function, but in different ways.
The primary difference between solar thermal and solar PV panels is how they work. Solar thermal panels capture energy from sunlight and convert it into heat or electricity using a heat-transfer fluid, such as water. In contrast, solar PV panels use photovoltaic cells to produce electricity.
Read on to learn more about how each type of solar panel works. We’ve also outlined the perks and drawbacks of installing each type in your home.
Overview of Solar Energy
Solar energy is a form of power produced through sunlight. The technology used to convert sunlight into usable energy was initially invented by A.E Becquerel in the mid-19th century.
Over a century later, solar panels became available to individuals and businesses. Since they emerged on the scene, solar panels have become more and more popular.
This rise in popularity was accelerated by the rising awareness of climate change and the danger of greenhouse gases. The main advantage of solar power is that it’s much more environmentally friendly compared to fossil fuels, such as coal and natural gas.
Solar PV Panels
Solar PV panels are the type that homeowners typically use to fulfil their houses’ energy requirements.
How Do Solar PV Panels Work?
Solar PV panels can serve their purpose of converting sunlight into electrical energy due to the material they’re made of.
These panels are crafted out of multiple layers. Two of those layers are made out of semiconducting materials, such as silicon. Sandwiched between these two layers are photovoltaic cells.
The electrical properties of this system allow it to create an electric field when photons from sunlight hit the panel. In turn, this induces an electric current. This process is referred to as the photoelectric effect.
Be noted that the current solar PV panels produce is DC. Before you can use this current to power appliances in your home, it needs to pass through an inverter that converts it into an AC current.
Here are the main pros of using solar PV panels:
Electricity Produced Is Never Wasted
The primary benefit of solar PV panels is that none of the electricity they produce goes to waste. Even if the panels produce more electricity than you need, you can store that excess power in a battery. Additionally, you can pump the extra electricity back into the national grid and get compensated financially.
Low Cost of Maintenance
Installing solar PV panels can come at a steep price. However, these panels’ cost is virtually zero once the installation is complete. The reason is that the maintenance cost for solar PV panels is practically non-existent. This remains true if you keep your panels clean and in good condition. Additionally, solar PV panels typically come with a 25-year warranty.
Can Power Your Entire Home
Another advantage of solar PV panels is that they can fulfil all of your house’s energy needs. They can power appliances, HVAC systems, lights, and much more. The same cannot be said for solar thermal panels, which we will discuss later in this guide.
Solar PV panels aren’t without their flaws. Here are a few of them:
High Upfront Cost
As previously mentioned, the initial cost of installing solar PV panels can be high and requires an investment by householders. However, the energy savings you enjoy as a result of solar PV panels still make them excellent investments in the long run.
They Take Up a Lot of Space
Another con of solar PV panels is that they require a lot of space. A solar PV system designed to power an entire house will take up around 45 square meters. Not only that, but solar PV panels aren’t to everyone’s tastes and can hurt your home’s aesthetic.
They Are Relatively Inefficient
Compared to solar thermal panels, solar PV panels are rather inefficient. At an average efficiency of 15-20%, solar PV panels are over three times less efficient than their solar thermal counterparts.
Solar Thermal Panels
The other main type of solar panel is solar thermal. These panels also convert sunlight into electric energy, as well as heat energy. However, they differ from solar PV panels because they use a heat-transfer fluid, such as water, instead of semiconductors to do so.
How Do Solar Thermal Panels Work?
Solar thermal panels capture energy from sunlight and convert it into heat energy using water. The heated water subsequently heats the surrounding environment. It can also be used to produce electricity.
In terms of hardware, solar thermal panels have flat-plate collectors. These are flat, dark surfaces enclosed in an insulated box. Solar thermal panels need to be dark to absorb energy from sunlight more efficiently.
A solar thermal system also consists of pipes that flow beneath the floor. These pipes radiate heat into the room as a result of the hot fluid running through them.
Here are the benefits of solar thermal vs. photovoltaic panels:
Lower Upfront Cost
Solar thermal panels are the better option for those looking to shift away from fossil fuels but are on a tight budget. This is because the installation cost of solar thermal panels is typically half that of solar PV.
More Efficient Than Solar PV
Another edge that solar thermal systems have over solar PV is that they’re more efficient. Solar thermal panels can convert sunlight into usable energy at up to 70% efficiency. As mentioned above this efficiency level dwarfs that of solar PV panels.
They Take Up Less Space
Finally, the higher efficiency of solar thermal panels means you need less of them to achieve the desired results. Therefore, they require less space than solar PV panels.
Needless to say, solar thermal panels have their fair share of problems.
Solar thermal panels typically only come with a 5 to 10-year warranty from the manufacturer. This warranty duration pales in comparison to the 25 years you can expect to get with solar PV panels.
Lots of Moving Parts
Another disadvantage of solar thermal panels is that they involve lots of moving parts. For starters, installing such panels involves significant plumbing.
Furthermore, you’ll need to replace the heat-transfer fluid at least every seven years. This means that the cost of the second replacement will have to come out of your own pocket since the warranty period will have ended.
Why You Should Install Solar Panels in Your Home
You may be wondering if installing solar panels in your home is actually worth it. The answer is that it is for sure, if your home is suitable for them..
Here are some of the benefits you’ll reap if you decide to pull the trigger on getting solar panels:
Saving on Energy Bills
The first advantage of having solar panels on your property is the reduced amount you’ll pay in energy bills.
As per the Energy Saving Trust, you can expect to save anything from £610 to £360 annually with solar, depending on how much you are home during the day (and therefore using the electricity produced).
Additionally, you can supplement your income thanks to solar panels. You can do so by sending any excess electricity your panels produce back into the grid and getting paid for it. This initiative is known as the Smart Export Guarantee (SEG).
Another benefit of installing solar panels in your home is that you’ll be much less dependent on the national grid. We all know too well how unreliable the grid can be at times. As a result, it’s great to have the peace of mind of knowing that you’ll always have electricity in your home even if there’s a power outage in your area.
Raising Your Property’s Value
Finally, installing solar panels on your property can actually raise its value substantially. This increased valuation can mean more money for you if you decide to sell your house.
It’s estimated that installing solar panels can raise your property’s value by as much as 14%.
Solar PV & Solar Thermal FAQs
Are solar thermal panels cheaper than solar PV?
In terms of the upfront cost of installation, solar thermal panels are significantly cheaper than solar PV. However, the higher energy bills savings and lower maintenance costs associated with solar PV panels make them a more cost-efficient investment in the long run.
Can solar thermal overheat?
Solar thermal panels can be prone to overheating at times. However, there are many things you can do to reduce the chances of this happening. These measures include installing a radiator heat dump or a pre-cooling vessel within your solar thermal system.
Solar PV v Solar Thermal Conclusions
When exploring your options in terms of solar panel systems to install on your property, you’ll come across two main types, solar PV and solar thermal.
Both these types are significantly more environmentally friendly than fossil fuels. Which one of them you should go for depends on how you intend to use it.
Solar PV panels are the better choice if you’re looking for a comprehensive solution to your home’s energy requirements. Solar thermal panels are an attractive option for those primarily looking for heating solutions.