We like to track innovations in solar technology, and keep our readers up to date on the latest creations and progress with turning solar into the mainstream alternative to the grid. The latest improvements in solar technology will make a serious impact for those who want to get off the grid for good.
In a previous article, we mentioned a photovoltaic coating called SolarWindow, which can be applied to existing windows to provide a solar power boost. An American company, New Energy Technologies (NET), has received federal assistance with moving to real-world applications of this technology. Government researchers at the National Renewable Energy Laboratory are helping NET to upgrade their existing photovoltaic design.
In the lab, NET’s PV coating has been used on window prototypes up to one foot square. They’re working to increase the number of cells that come into contact with the window surface, and to find lower-cost materials to use for the PV coatings. NET’s SolarWindow films are intended for future use in both commercial and residential buildings.
The U.S. government is promoting alternative energy start-ups like NET not only increase alternative energy options for consumers, but to jump-start production in the small business and energy sectors.
Pythagoras Solar Transparent Photovoltaic Windows
The Sears Tower, now known as the Willis Tower, is a testing ground for a new type of transparent solar window. Pythagoras Solar is testing a prototype two-foot-square solar window in the southern face of the building. If successful, the tower’s owners plan to replace all windows in the tower’s southern side with the PV windows.
The prototype contains mini solar cells layered inside a double-paned window, and it was installed as a regular window section on the tower’s southern side. The miniature PV cells maintain a 14.1% efficiency even though the window is vertical and fixed, and not angled toward the sun. The company estimates that if all of the south-facing windows are replaced with their PV windows, the tower may be able to produce as much as 2 megawatts of power per day.
Pythagoras also developed a new cell technology to improve their window’s efficiency – the cells operate independently of each other, which allows the individual cells to continue functioning when adjoining cells fail. Traditional PV cells are interlinked, and the failure of one cell can cause a cascade that takes out an entire series of cells.
These transparent windows permit light to pass through while capturing solar energy to produce power. The window’s efficient conversion rate and low profile would allow it to replace windows in any building where natural lighting is a requirement and the occupants expect to still have a view of the outside world.
Dyesol Solar Panels
This Australian company has created a solar product that could pass as magic. Dyesol’s innovative solar cells can provide energy, even when located in a dark room. An article on their products recounts a meeting in Dyesol’s boardroom where two fans were hooked up to one of Dyesol’s solar panels. The blinds were drawn, the lights were off, and the panel was shadowed – and the fans kept spinning.
This is the greatest technological leap yet for solar power – the ability to function and provide power in low light conditions.
Dyesol originally came to notice as an innovative energy company after developing a solar paint that could be applied to steel roofing and building components to provide extra power, and their production process differs radically from that of traditional solar panels and films. We’ve commented on their solar paint in previous articles as well, noting that this type of solar cell provides for something akin to photosynthesis.
Their process, which creates solar cells and panels that are less expensive to produce than silicon-based PV panels, involves an electrolyte, a layer of titania, and ruthenium dye. These layers are sandwiched inside glass, or are sprayed on metal sheets as layers of paint. Light stimulates electrons in the dye and the electrons are absorbed by the layer of titania, creating an electric current.
This process not only helps reduce production costs, it provides energy under less than optimal conditions and is not sensitive to temperature changes. Dyesol’s solar paint does not contain diodes, and is less prone to breakdown or degradation. The solar paint can be applied to nearly any material.
A surface with the solar paint on both sides can absorb light on both sides, in direct contrast to PV panels that can only absorb light from one direction. The company refers to their panels as “light sponges” capable of higher than 11% peak efficiency when turning sunlight into electricity. We look forward to seeing their test production facility up and running within the next year, and toward the future of low-light solar energy production.