Solar Panels Through Glass (Efficiency Report)

Initially, the solar panels were limited and had low KW potential; however, the technology of solar panels has increased in recent years, increasing efficiency in all conditions, including through glass, but is it effective?

Today solar panels come in all different shapes and sizes, have higher KW potentials, and can even be installed in your windows or behind clear glass.

Of course, the efficiency varies as well. So are you wondering how solar panels can work through glass?

We’ll guide you about the following:

  • What is solar energy, and how it works?
  • What are solar panels, and how do they work?
  • Can solar panels work through glass?
  • The concept of solar windows
  • How can solar panels be optimized to work more efficiently behind glass?

Let’s find out if they work through glass and the efficiency of the solar panel.

Solar Panel Indoor
A Solar Panel Indoor

Can Solar Panels Work Through Glass?

Yes, solar panels can be used through glass windows. However, their efficiency will not even be close to what it would be if they were placed in an open space where they could encounter direct sunlight.

The reduced efficiency will be reduced by up to 50%. This figure varies depending on the strength of the sunlight, efficiency of the panels, glass type, thickness of glass, and cleanliness.

These solar panels will continue working even if they receive sunlight through glass. Still, their effectiveness and power outputs will be significantly lower than their nominal values.

Thus, they will work, but their performance will be compromised. The reason behind this loss is a simple law of physics called the Fresnel Law.

Fresnel Law

Fresnel Law describes the phenomena of refraction of light inside a surface. In simple terms, light can be described as a wave or a particle (photon).

As these light rays travel to the earth from the sun, they have a specific direction and speed.

Suppose the ray of light reaches another surface before it reaches the earth’s surface. In that case, some part of it is refracted inside every surface, and the rest is reflected into the air, and this entire process occurs according to the Fresnel Law.

So, according to this law, if the incoming solar radiation reaches another media, such as glass, before it reaches the surface of the solar panel, then a part of the radiation will be reflected by the glass. At the same time, a part of it will refract inside the surface of the glass at a different speed and angle.

And according to the type of glass the radiation encounters, the angle and speed will be variable.

Solar panel and Li-ion battery generation system for home. Renewable energy concept. Simplified diagram of an off-grid system. Solar panel, battery, charge controller, and inverter. Vector.

See also: How Efficient are Solar Panels? Unveiling the Truth About Their Performance and Cost-Saving Potential

the efficiency of solar panels behind a glass

Suppose the light rays are refracted inside the glass surface before reaching the surface of the solar panels. In that case, logically, the number of photons reaching the solar panel will be less because of all the sunlight lost as a consequence of reflection by the glass.

Thus, the amount of electricity generated by the panel will be less than the panel’s potential.

In this case, the number of losses will differ depending on the type of glass and its reflection factor; however, the energy output of solar panels will still be radically reduced.

Reasons Why Solar Panels are Put Behind Glass

There are several reasons why solar panels are placed behind glass.

  • With more portable choices like smaller battery packs, leaving devices like phones or laptops in your car to charge has become a suitable option while traveling.
  • You are residing in a neighborhood where they could be robbed. Solar panels are not inexpensive. Also, if you just require a small panel and do not wish to secure it on the roof, you might be concerned about putting it in the yard where it might be looted.
  • A camper or motorhome is one of the most popular sites where solar panels are hidden behind glass. Many individuals either don’t have the space or do not want to drill holes in the rooftop to put panels. However, the big windows offer an excellent location for a parked panel.
High Efficiency Solar Panels

How can solar panels be optimized to work more efficiently behind glass?

If you continue to put in force the use of solar array behind glass, the following belongings are required to optimize in gaining valuable amounts of electricity:

  • Induce the maximum direct sunlight on the panel by using a south-facing window.
  • A small portable panel can offer the utmost amount of sunlight throughout the day as it can be moved to different positions where maximum sunlight is available.
  • To minimize the loss of energy from refraction or shading from windows or other objects, the panels should be placed nearest to the glass as possible.
  • Another simplest option can be opening a window and permitting daylight.
Car Park Solar Canopy

What Are Solar Windows and How Do They Work?

An alternative to putting solar panels behind glass is using a more innovative technology called ‘solar windows’ in which your glass windows are converted into solar windows.

This is an advanced and innovative technology that allows electricity generation more feasibly.

With the progression of technology and expansion of the solar market, solar companies are exploring new technologies that help solar energy generation past the conventional rooftop and ground-mount panels.

Solar windows are the recent advancement in this domain and represent a glimpse into the future of the solar world.

Any technology that uses windows to generate electricity from incoming solar radiation can be termed a solar window.

This technology is also termed ‘solar glass’. Currently, this technology is not prepared to be commercialized, so one cannot just install a solar window in their house yet.

However, many solar window technologies currently under development show great potential to be introduced in the solar market soon.

Theoretically, the translucent window panels would be able to substitute the conventional window panes, while traditional solar panels are an addition to a formerly installed roof system.

As a result, this type of solar technology is often referred to as “building-integrated photovoltaic (BIPV).”

So, the question is, why isn’t this solar window technology everywhere, and not many people are aware of it?

The simple answer is functionality. To get efficient energy production, incoming light should be able to pass through windows that act as solar panels and light up the room.

A solar window that cannot allow sufficient light to pass through is as bad as a conventional panel installed in a vertically mounted position where insufficient sunlight reaches it.

If the widow panel lets more than sufficient light pass through, the solar window panel system will not be able to generate adequate, cost-effective electricity.

Thus, to make an impact in the solar market and become commercially viable, this solar window technology needs to be rightfully building-integrated and inconspicuous, which can be achieved using non-opaque or see-through window panel technology.

Solar Cell Type Efficiency

Can Solar Panels Work Indoors?

Solar panels work best under natural sunlight as they are the most abundant and intense light source for their efficient working, and most solar systems are designed for outdoor regions.

However, solar panels can work with artificial light sources indoors as well, but their output and efficiency would be significantly reduced.

Incandescent, compact fluorescent, and LED light bulbs are the best artificial alternatives for natural sunlight to power a solar panel. They can imitate similar energy as the sun but can only be used to power small solar devices.

Can Solar Panels Work Through Tinted Glass?

It is clearly understood that solar panels can be utilized to their full potential if they have direct exposure to sufficient sunlight.

If solar panels are being used indoors behind a tinted glass, say behind a vehicle’s tinted window, it will significantly impact the working potential of that panel. Still, as long as it is exposed to some sunlight, the panel will work.

The tint on the window would obstruct only half of the sunlight that strikes its surface; however, the remaining half would be able to penetrate through the tinted glass and reach the panel to power it.

Can Solar Panels Work Through Plastic?

Solar Panels can most definitely work through clear plastic. However, we must keep in mind that there are different varieties of plastic as well, and all of them are different from one another in some ways.

The type of plastic determines how effectively a solar panel would work. The general perception is that using plastic would reduce the efficiency of a solar panel but under certain circumstances, it is deemed a more suitable option.

Recent research has led scientists to discover that plastic can serve as a very viable photovoltaic element itself and the development of plastic solar cells is in progress these days as they would be more durable and less expensive.

Can Solar Panels Work Through Plexiglass?

Plexiglass is a type of plastic called acrylic sheet or acrylic glass. This material is considered a sturdy, durable, and safer alternative to glass or other types of plastic.

It is considered a favorite material in the construction of solar panels compared to tempered glass because it is more durable, sits well under harsh weather conditions, and is shatter-resistant.

Along with this, this material allows more than a sufficient amount of sunlight to pass through to the solar panel, making it an excellent choice for constructing solar panels.

Should You Take Off the Plastic Covering From a Solar Panel?

For a solar panel to work under a plastic covering, we first need to understand what type of plastic covering is being used to cover the panel.

As mentioned above, solar panels can work through clear plastic with slightly reduced efficacy.

Acrylic sheets, Plexiglas, Polycarbonate, and Polypropylene, are some of the plastic sheet coverings that can let enough light pass through for the efficient working of a solar panel.


To conclude the present study, solar panels work when installed behind glass or plastic but do not produce results efficiently.

Numbers of reasons are explained as to why solar panels should not be placed behind windows/glass. However, it does not mean that solar panels will not operate, but their performance will be compromised.

Therefore, it is worth it to purchase solar panels but it is not recommended to place the solar panels behind glass. It truly relies upon what you need.

Putting solar panels behind glass or plastic is not plausible if you are endeavoring to control your whole house.

In any case, if you simply need to charge a cell phone or some little devices on a train, you ought to have the option to do that.

Photo of author
Elliot has 20+ years of experience in renewable technology, from conservation to efficient living. His passion is to help others achieve independent off-grid living.

SolVoltaics is an affiliate and an Amazon Associate, we earn from qualifying purchases - at no extra cost to you.