Solar windows are windows that function as solar panels to harvest the sun’s energy and convert it to electricity. Building owners can purchase solar windows to replace existing windows or buy solar film to retrofit existing windows.
There are a variety of solar windows available, but what exactly are the benefits and challenges of this new technology?
TYPES OF SOLAR WINDOWS
Solar windows are available as separate units or are created by applying a photovoltaic film onto window glass. Some manufacturers create independent solar windows by sandwiching existing solar panel cells between two layers of glass. Although the solar cells are visible, the human eye skips over the cells when looking out the window.
Other independent window units are made from photovoltaic glass. “Invisible wires” collect the energy made from the photovoltaic glass and transfer it to the energy grid. These panels work by using thin-film technology to apply a very lean coating of the photovoltaic onto a conductive glass layer.
Photovoltaic films allow building owners to modify their existing windows installing a film on the inside surface of the glass. The film is made from mostly organic materials, such as carbon, nitrogen, hydrogen, and oxygen, that are applied in liquid form to a stabilizing layer.
POTENTIAL BENEFITS OF SOLAR WINDOWS
The visual impact and space requirements of solar panels have prevented large-scale adoption. Solar windows can replace existing windows and can help building owners achieve partial independence from the energy grid.
Dense urban areas could benefit from this technology because of the large vertical window space and the lack of rooftops for solar panels. Solar windows could also help offset peak energy demands.
Photovoltaic films have even more advantages. Contractors can apply these films to existing windows, so there’s less waste involved in upgrading to solar windows.
Photovoltaic films are also lightweight, which means there’s less embodied energy required for their manufacture and transport. Researchers also believe they will be able to offer a 25-year warranty, which is similar to the current coverage on solar panels.
TECHNOLOGICAL CHALLENGES OF SOLAR WINDOWS
Solar windows are a new technology, so there are several disadvantages that manufacturers are still working to overcome.
The visual impact and space requirements of solar panels have prevented large-scale adoption.
Solar windows cost an estimated 40 percent more than traditional windows. Traditional solar panels are more efficient and cost effective than solar windows. Therefore building owners who have the space for solar panels may not be interested in solar windows.
Solar films that are placed on existing windows are transparent but not clear. They may have an orange, blue, or green tint that impacts the view and light quality. Some photovoltaic glass windows may also have a slight tint, but some tech companies report they can create completely clear solar panels.
Some of the largest advances in solar window technology are not yet available for purchase. SolarWindow coatings that are applied to the inside of existing windows won’t be manufactured until at least 2019. Many revolutionary solar windows currently only exist in a laboratory setting.
Regardless, solar windows could transform the photovoltaics industry, but there has not yet been enough real-world testing to know if the technology will be financially viable.
For building owners who don’t have the room for traditional solar panels, or who are interested in supporting this emerging industry, solar windows are an attractive option. To learn more about how you can benefit from solar power contact CAM Solar today.