Solar windows: Can you install solar glass windows?

Solar windows are an exciting technology that lets you generate electricity from more than just rooftop panels. As the solar market evolves and expands, companies are looking into new solar technologies to spread solar energy generation beyond traditional rooftop and ground-mount solar panels. Solar windows have gained momentum recently and could represent the future of the solar market.

Any technology that uses windows on buildings to generate electricity from the sun could be classified as a solar panel window. Solar window technology (sometimes called solar glass) isn't ready for commercial production yet, so it isn't available to install in your home. However, several solar window technologies that could hit the mass market shortly are being developed.

Transparent solar panel windows would hypothetically be able to replace standard glass window panes, while traditional solar panels are an addition to a previously installed roof. As a result, this type of solar technology is often called "building-integrated photovoltaics (BIPV)." Tesla's solar roof is another recent technology under the BIPV umbrella. BIPV technologies offer many potential benefits – many homeowners love them because they can be much more aesthetically appealing and easier to maintain than traditional solar options, depending on the type of installation.

Why isn't solar glass technology everywhere? The simple answer is functionality. Traditional opaque solar panels use photovoltaic technology, meaning they capture energy in the form of light and use it to generate electricity. Because windows are meant to let light through, windows that act as solar panels need to reconcile letting incoming light through to illuminate a room and capture incoming light for energy production. A solar window that doesn't let enough light acts as a vertically mounted solar panel; if it lets too much light in, the window can't generate enough electricity to be cost-effective. For solar panel windows to impact the solar market, they need to become truly building-integrated and unobtrusive by utilizing transparent solar panel technology.

Several technologies in development or early production stages fall under the umbrella of "solar windows."

Physee PowerWindows

The power-producing edge of a PowerWindow

The only currently installed solar windows are made by Physee, called PowerWindow. Physee's product uses small solar panels installed along the edges of glass panes to generate electricity from the sun. They are only installed in one building in the world, a Dutch bank with over 300 square feet of the PowerWindows. The windows generate enough power to charge a smartphone a few times a day and can't act as a standalone power source for buildings yet.

Transparent solar panels

When it comes to solar panel windows that generate power from the glass itself, the technology is much further away. The key to a future with true transparent solar windows may involve nanotechnology. If windows can be designed with quantum dot technology, enough energy may be harnessed from the sun while still letting light through the glass window pane in which the quantum dots are housed.

In theory, quantum dots embedded in glass windows would be able to absorb light and re-emit it as infrared light towards solar cells housed at the edges of window panels, which would be used to generate power. Again, this technology is unavailable yet and may not be for years, but it represents an opportunity to make fully transparent solar panel windows a reality.

Solar panel blinds

Solar blinds on a window

One similar solution currently in late-stage development is solar panel blinds. Instead of the actual window producing energy, a company has designed blinds that can be hung inside or outside a window with small solar panels installed along them. The blinds can automatically rotate to follow the sun throughout the day, optimizing energy production and efficiency.

Solar windows are barely beginning to touch the market and remain highly inefficient and expensive. While solar panel windows aren't commercially available yet, the cost of installing traditional solar panels is falling rapidly, and advances in manufacturing mean that they are more efficient than ever. Visit the EnergySage Solar Marketplace to receive competitive quotes for your property from reputable local installers. Whether your top priority is aesthetics, long-term savings, or initial investment, reviewing and comparing offers from multiple providers is the best way to solar shop for your home effectively and intelligently.