Solar Windows: How Much Energy Does Solar Glass Produce? (Full Guide)

Solar windows are pre-manufactured or converted traditional windows that function on the same solar energy generating principles as solar panels. This relatively new solar-panel inspired product has numerous names, but they all mean the same thing.

Solar windows are also known as:

• Solar glass
• Photovoltaic glass
• Transparent solar windows
• See through solar windows
• See through solar panels
• Solar panel windows
• Transparent solar concentrator

But, how does solar glass work? Can it generate the same levels of power that solar panel roof replacement can?

This complete guide explains how Solar windows work, how they can supplement your energy needs and the amount of energy they can provide.

Solar Windows Technology Basics

Solar window technology is not is not practical enough yet for wide-scale commercial or residential use. The technology is officially still in the experimental and prototype stages of development.

Solar window technology has a lot of promise for future applications, but currently is only just a fraction as efficient in generating solar-derived energy as traditional solar panels.

In 2017, all of the windows of a Dutch bank Rabobank branch were outfitted with solar windows by solar window company Physee.² The experiment was performed for proof of concept purposes.

While the technology worked, the windows could only generate 8 to 10 watts of electricity. That is barely enough energy to power a light bulb.

So, let’s talk about how much energy solar glass technology can really produce. While it may not be practical for you to get solar windows now, or even possible depending on where you live, this is a technology to watch in the future.

Firstly, let’s briefly talk about how solar panels work for some additional context. After all, solar window technology was inspired by solar panels in the first place.

Related Reading: Solar Panel Efficiency Over Time

How Do Solar Windows Work?

The easiest way to discuss solar windows, how they operate, and how much electricity can be generated by them, is to first talk briefly about solar panel technology.³

Solar panels are sunlight siphoning panel surfaces that are made from semiconductors, photovoltaic cells, and other components. As sunlight energy, which are also known as photons, shine directly on a solar panel, the photovoltaic cells and semiconductor technology inside the panels separate the electrons from the photon atoms.

This process generates electricity from sunlight harvesting.

The sunlight-generated electricity creates a DC current which must then be converted into AC. After this conversion, the solar panel energy can be utilized by a residential home, commercial facility, saved in a battery, or sold to a local utility.

Solar panels are affordable, can be subsidized by local tax rebates, and be conveniently set up as long as your local climate receives up to four hours of direct sunlight for maximum efficiency.

Depending on where you live, your circumstances, and the amount of solar panels that you install on your property, your solar panels could produce up to 850 kWh of electricity every year.⁴ For added context, the typical American household utilizes anywhere between 886 kWh to over 10,600 kWh per month.⁵

Solar panels are a great way to supplement your everyday energy needs and save money. The more solar panels that you own, the more energy you can generate and the more money you can save.

The typical solar panel has an efficiency rating of about 23%.⁶ That means that over 23% of the sunlight that hits the solar panel is converted into electricity.

The next-gen solar panels that will be developed in the coming years and decades will be as much as 50% efficient in capturing sunlight energy.⁷

Solar panel technology has been scientifically proven and to have inherent benefits that will usher in the renewable energy technology revolution of the future.⁸

However, solar panel technology has several drawbacks that could potentially cause its hardware to become semi-obsolete in the future, or dramatically repurposed, while its operational functionality could continue to thrive in the form of solar windows.

Related Reading: 46 Solar Energy Facts

See Through Solar Panel (Solar Glass)

A solar window is a see through solar panel variant with a few modifications. A group of MIT students created the modern version of the solar window back in 2014.⁹

They even started a company called Ubiquitous Energy based on their research concepts. A solar window is a transparent version of the traditional solar panel, which is opaque.

The semiconductor and photovoltaic cell technology found within traditional solar panel technology require that the solar cells are a black and opaque color. Solar cells are usually black and non-transparent because they are designed to siphon and capture any direct and indirect ambient sunlight energy that comes in contact with the cells.

If solar panels were transparent, then sunlight would pass through them. Sunlight energy could not be captured by the photovoltaic cells and semiconductors to convert into electricity.

Solar glass is designed to allow sunlight to pass through it, like any traditional window, while still generating solar-based energy.

Solar Glass (Solar Powered Windows)

Solar glass, or solar windows, are traditional windows that are prefabricated or chemically and electronically treated to act as transparent solar panels.

Transparent glass has wires run through them and are either coated with a proprietary photovoltaic glaze or a microtint made of an organic dye.

The photovoltaic glaze or organic dyes are designed to replace the functionality of traditional photovoltaic solar cells.

Solar windows are not 100% transparent – they feature a noticeable but transparent hue or tint. It is that tint which allows light to pass through while still generating energy. The visible tint you see on a solar window is hundreds of times thinner than a human hair.

The operational premise of solar windows is based on experimental quantum dot technology,¹⁰ which is currently still being perfected.

Quantum dot technology is technology that shrinks traditional solar panel conductor technology to nanometer scale to allow sunlight to pass through the window while generating energy from other wave spectrums of light. (While this technology sounds promising, it must be noted that quantum dot technology is still in the theoretical phase.)¹⁰

Since solar windows can’t efficiently capture the sunlight passing through it, the photovoltaic glaze or tinting is designed to capture ultraviolet and infrared light. Solar windows convert ultraviolet and infrared light into electricity while sunlight passes through.

This aspect of the technology is necessary for the window to be transparent.

It has been estimated that there are over 20 billion panes of glass in every skyscraper, residential home, and building-like structure in the world.¹¹ Solar window technology is proprietary and always evolving depending on the company manufacturing it.

So, it could potentially be retroactively applied to every existing home in the world and built into new structures. The skyscrapers and residential homes of the world could one day become the globally reaching solar farms of the future.

Traditional solar panels are bulky, aesthetically unpleasing to the eye, and are usually installed on rooftops or in deserts in large solar panel farms. The infrastructure and electrical systems of a residential home must be radically adapted to accommodate solar panel technology.

And it can be expensive and work-intensive to repair, move and relocate solar panels. Replacing a solar window could be as work-intensive as replacing a traditional window in the future.

Unless you look for the tell-tale tinting or some wiring, solar windows are virtually indistinguishable from traditional windows. The property values of homes in the future could be positively affected by the aesthetic benefits of solar windows.

However, the proposed benefits of solar windows are currently stuck in the experimental and developmental stage. Barring a few small companies, the industrial implementation of a solar window infrastructure on a wide scale is probably decades away.

Why? Because as of right now solar window technology is fractured amongst competitors, inefficient, and unavailable for widespread consumer use.

And they just don’t generate a lot of energy to be a viable alternative to traditional solar panel technology yet.

Solar Panel Windows: How Much Energy Do They Generate?

The energy generated by solar windows are generally negligible compared to their traditional solar panel counterparts.

Solar panel technology can generate energy at about 23% efficiency. That means that about 23% of the sunlight hitting the panels is converted into energy.

Some new solar panel models feature almost 50% efficiency.

The more solar panels you own, the more you can compensate for existing 23% efficiency rates.

The typical solar window features 7% to 15% energy conversion efficiency.¹² That means at worst, a solar window might convert 7% of the sunlight that passes through it into energy.

And even at best, 15% is still a lot less than 23%. There is no general consensus about how much energy solar windows can reliably produce since it is still an experimental and emerging technology.

The amount of potential energy generated differs according to the proprietary technology of the company producing the solar window, and there are a few. Some experts say that solar windows can generate anywhere between 8 to 10 watts daily.¹³

Ubiquitous Energy, the company that allegedly started the race for the perfect solar window, currently claims that its product can generate 200 watts of energy daily.¹⁴

For comparative context, 8 watts of energy could power a light bulb. A medium-sized TV or kitchen appliance could be powered for a while with 200 watts.

Solar Window Shades

Solar window shades are an experimental product that incorporates solar panel technology into window shade-shaped hardware.

Solar Window Air Conditioner

A solar window air conditioner is an air conditioner that features a mounted solar panel on it. The air conditioner gets its power from the solar panel unit.

Solar Panel Sun Tracker

A solar panel sun tracker is a device that automatically follows the sun as it transits the sky to always receive direct solar energy. Desert-based solar energy farms utilize solar panel sun tracker technology.

Should you get solar windows? Unless you are interested in the novelty, can coordinate testing arrangements with a manufacturer, or are OK with low-energy generation, you may want to wait.

Solar window technology is not a fluke – the technological theories are sound and are based on existing solar panel technology. But they just are just not ready for prime time yet.

Understand how solar windows and solar glass options work can help you plan and build your green energy system using a variety of options.

Frequently Asked Questions About Solar Windows