SolarWindow is a new see-through electricity generating coating technology designed for glass windows for tall towers, skyscrapers and detached homes in the US. The company claims the product has the potential to offset 30 to 50 percent of the energy demand when installed on a 50-story building - with a calculated one-year financial payback.
SolarWindow has been developed to performance standards in order to give real estate developers, engineers, architects, building designers, and future customers plenty of financial incentive and it has been rigorously tested for durability, degradation, and performance.
REM talked to SolarWindow President and CEO John Conklin to find out more.
Tell me about the company
SolarWindow Technology is developing the first of its kind electricity generating coating which is transparent for windows and flexible plastic and the product is targeted for over 5 million commercial buildings and 80 million detached homes, just in the United States alone. Certainly our mission is pretty simple and that is to create solar window products which produce clean energy, is economically feasible, has a very short ROI and benefits the environment.
How were these windows developed and how do they work?
SolarWindow is a transparent coating that is primarily organic. Basically we combine carbon, hydrogen, nitrogen, oxygen and create our device that generates electricity. We constantly refine our layers based on colour and light transmission or transparency so that we can extract the power that we need from the window to satisfy a building energy demand.
How do these windows perform with regard to electricity generation when compared to PV systems?
There are some distinct differences in that SolarWindow is a technology that is based on transparency, a technology that has been developed for a window and not a coating that has been developed for a tablet or electronic reader and then we apply it to a glass window. The inception of its early-stage prototype has been developed for windows, specifically tall towers and skyscrapers. The importance there is the transparency, the other thing to keep in mind being that we are going vertical with that valuable glass real estate. When we look at conventional PV and putting that on the roof of a tall tower or skyscraper, there is very little surface area for those modules to generate meaningful power. When we look at the vast surface area of all four sides of a tall tower or skyscraper, that presents valuable real estate to us by which SolarWindow can take a passive, energy saving window and turn it into an active energy generating window that helps produce a meaningful offset of the building energy demand.
From what I read of your product, the windows can perform when installed on all sides of a building. How does that work?
That is one of the beauties of the technology. Conventional PV, whether crystalline PV or thin-film PV, really requires, in the Northern Hemisphere, a southern orientation. That is really important for that type of PV because the orientation allows the maximum sunlight to hit those panels to generate electricity. As you change that angle, it moves further east or west, it loses the ability to generate electricity and then you really have to rely on early morning sun or very late day sun and that is a very limited time of the day. SolarWindow has been developed to work not only when exposed to natural sunlight but it can also generate electricity when exposed to artificial light and that is not limited to only incandescent fluorescent lamps, LEDs, halogen lamps, it can generate electricity under any of those, but to go one step further, we don’t need a complete southern exposure for the technology to work. Our technology works under very low light conditions, diffused light, shaded light. More importantly, when we look at a building, there is always that northern face that doesn’t see direct sunlight. However, because we can generate energy from reflected light as well, it allows us to coat the entire building, all four sides, with the SolarWindow and be able to produce meaningful power under all of those artificial and sunlight conditions. The diversity of light conditions is a feature, allowing us to generate under all of those low and diffused light conditions including reflected light.
Why are these windows coloured rather than truly transparent?
They are coloured but they are also transparent, and keep in mind that our target is those tall towers and skyscrapers, the glass in those windows is generally tinted and it serves a number of purposes. First, it helps with heat and reflecting that light to control heat. It is also required by architects for the very aesthetically appealing features of the building and some of those windows are either very dark or have a mirror finish to them. So when we were developing SolarWindow, the objective was to develop the product that provides colour options that are available to architects, building developers, building owners and engineers that need those design bases for those tall towers and skyscrapers.
The sheets of glass in the pictures on your website seem rather small to me, is it possible to produce any larger sheets?
Those are only development steps, the product itself and the coating methods we are using are for large area sheet-to-sheet coating, which means that we are looking at coating 18 feet by 18 feet panes of glass and we are also looking at the high speed roll to roll coating so we are looking at coating 10,000 feet in ten minutes, so our coating methods are being developed for those very large area or high speed volume manufacturing.
What stage is this at? Is there demand for these windows yet and when will they be commercially available?
We have been talking with many of the glass industry manufacturers around the world. These companies span the glass industry, from the companies that make the sheets of glass right through to the fabricators that actually build the windows and there is tremendous interest in SolarWindow, primarily because of the growing glass market and the rising energy demand. We believe, moving forward through our commercialisation timing and when we are actually going to bring this to a product for sale, that there will be continued and heightened interest, moving forward.
We are looking at year end 2017. That’s predicated on a couple of very important development objectives. We are certainly in the process of raising capital, and that’s critical. Next is formulating strategic relationships in the glass, energy and chemical industries. That will give us instant outreach to the building segment and the ability to put our product in our better, faster ways. Third is, with those strategic partnerships, to build those SolarWindows that are ready for commercial production.
What plans have you got for future growth/expansion?
Looking at SolarWindows from two perspectives, the first and most important is the development of the SolarWindow product. The second objective is the electricity-generating coating in itself. So as we build out the SolarWindow product, we are on a parallel path to developing other products that utilise our transparent electricity-generating coating. As the company continues to develop these products, we will licence our technology, the licence being in the form of a licenced product, licencing the technology and know-how, licencing to a territory or a geographic region and then finally licencing the technology for a field of use. The development of the company will keep in mind each of those licencing models and thus keep the company moving forward through to the next ten years.
Anything else you would like to mention?
The most important thing to keep in mind is that right now, the tall towers and skyscrapers do not have a way of offsetting energy. It’s going to be critical for those structures, moving forward, to look at their carbon footprint, to determine how they can offset their increasing energy demand and go beyond energy management and energy conservation devices. They will be looking toward generating renewable energy and by doing so, not taking up valuable urban or rural land to do so, and being able to utilise the vast surfaces on those buildings to generate the energy required to offset the energy demand. I believe that we are, right now, approaching a very critical time in renewable energy in that SolarWindow may be one of the biggest single breakthroughs in clean energy, ever.
For additional information: