Photovoltaic fabric structures add function to form and energy to aesthetics.
By Janice Kleinschmidt
Power is literally in the hands of today’s fabric structure makers—and the forecast looks bright for any fabric-related business that looks to the sun for advantage.
“I think every fabric product manufacturer in the future is going to be selling power as much as selling function in their product,” says Todd Dalland, co-founder and president of New York City-based FTL Solar LLC and Pvilion Inc. “The whole industry is going to change. Once you have discovered ‘electric’ fabric, fabric will never be the same.”
Dalland has been working exclusively on fabric structures since starting FTL (Future Tents Ltd.) Design Engineering Studio in 1977. In 1998, FTL designed what he says is the world’s first photovoltaic tent for an exhibition at Cooper-Hewitt, National Design Museum, Smithsonian Institution, in New York. In 2006, he and Robert Lerner founded FTL Solar to design and manufacture photovoltaic tents and fold-up battery chargers. In July 2011, they and electrical engineer Colin Touhey started Pvilion, to make turnkey products with photovoltaics on flexible materials such as fabric.
FTL Solar’s earliest products included solar-powered tents and charging stations for the U.S. Army. A recent Pvilion client is the Pflugerville (Texas) Community Development Center (near Austin), which is building an industrial park. “They’re trying to attract the alternative energy industry, so they’re using canopies, covered walkways and solar light poles throughout the development as in indication of their intent to support renewable energy,” Dalland says.
“Our goal is to help introduce photovoltaic technology to all of the fabric structure industry. We are talking to awning companies, sailboat sail makers, truck tarp, boat cover and geotextile companies.” Long-distance haulers that keep their engines running to heat or cool the interior while they’re parked could instead gather solar energy with PV truck tarps. In the geotextiles arena, Dalland and his partners have produced a concept for turning ‘brown’ fields into ‘green’ fields. Fragile caps covering acres of toxic waste can be covered with lightweight fabric that generates clean energy.
“Another area is covered parking lots,” Dalland says. “The fabric is shading the car as it always did, but it becomes a power plant for a shopping center or an office building.” The growing popularity of electric cars makes the availability of remote power stations a real attraction.
Shade and sun, energy and identity
Remote power generation is a market specifically being targeted by ShadePlex LLC of Toledo, Ohio. “We started the company [in 2007] specifically to go after the intersection of shade and solar,” says president Brian Tell. “We are targeting designers, developers and installers of parking canopies and recreation shade structures. We have another application geared specifically for large tents and clearspans, targeting the military, disaster relief agencies, corporations that might have remote operations and tent rental companies.” One installation is a canopy in a park in Australia used to power electric barbecue stations.
“We have a tent product that we will be bringing to market soon,” Tell reveals. “It’s a package of fabric-mounted flexible solar panels—and then we have a system for the inverter, batteries and charging controls. It will be a complete solution.”
SMIT (Sustainably Minded Interactive Technology), a design firm in Brooklyn, N.Y., announced the launch of lightweight, customizable membrane structures called Tensile Solar in 2011. “We have had a tremendous amount of feedback from our initial launch. We have been contacted by architectural firms,” says CEO Samuel Cochran, adding that one such firm is considering Tensile Solar for a large residential project in Abu Dhabi, United Arab Emirates. “They want the project to be energy negative,” Cochran says, noting the use of the structures to provide shade, power lighting and collect rainwater for gray-water use.
SMIT’s first commercial product, Solar Ivy, offers the ultimate shade-and-solar customization with individual leaves that can be increased or decreased in density depending on visibility or architectural needs, and adjusted in pitch not only for aesthetics but also for maximum sun exposure. Mimicking ivy, it can even be installed on a building façade and over windows. The “leaves” are available in colors, which means they can be used to “paint” a corporate name or logo—adding branding to their functionality. The stainless steel mesh that roots Solar Ivy to a structure is flexible enough to bend and curve around contours, and the modular design makes it possible to update an installation as new photovoltaic technology becomes available.
The U.S. military has been an early adopter of photovoltaic fabric products “so soldiers don’t leave trails of batteries, and it reduces the amount of refueling,” says solar designer and consultant Amelia Amon, Alt. Technica, New York City, N.Y. “One of the things I am looking at is solar awnings, 10-by-10 structures that can be used to collect rainwater and light streets.”
In January, Birdair Inc., a tensile structure contractor in Amherst, N.Y., began its portion of an addition to the Staten Island Children’s Museum in Staten Island, N.Y. The solar and wind power demonstration space, called Meadow Structure, features a 3,000-square-foot, translucent, photovoltaic fabric roof. The system uses thin-film photovoltaic panels on Teflon®-coated fabric.
“Teflon-coated fiberglass fabric is the material most commonly used by Birdair,” says Brian Dentinger, director of quality. “It’s the longest-lasting architectural fabric. It has been in use for 40 years and is now on all seven continents.” Birdair is also looking at retrofitting larger structures it has done to make them solar-power generators. And, Dentinger notes, “We’ve had a lot of interest in covering parking lots. I think that’s one [photovoltaic fabric application] you are going to see.”
The light stuff
While great strides are being made in designing new types of power-generating structures, incorporating photovoltaic technology into an established product may present challenges.
“It’s not as simple as just fitting your existing fabric product with photovoltaic panels, because there are other considerations, like how your fabric structure folds up,” Dalland says. “In most of the industry, fabric structures are relocatable. Photovoltaics at this point are not as flexible as the fabric. Panels come in rectangles, and the original product has to be redesigned with this in mind. When you put the panels onto fabric, they weigh more than the fabric without them, so how they’re tensioned, how they resist flutter in the wind, requires redesign.” Additionally, he notes, manufacturers may need to reconfigure their assembly line to accommodate the way the heavier fabric behaves as it’s moved around their shop and/or change their packing methods to avoid creasing the flexible photovoltaic panels.
On the other hand, Dalland notes, you can use the same material and equipment. “You just have to use them differently,” he says. “When you switch to electric fabric, now you are a power company and you have to integrate electric wire into the fabric product. All of the fabric panels have to be wired together. … You will need electrical expertise to determine how much power you will generate and [to understand] electrical code manufacturing standards.”
SMIT concentrates on design and then partners with an electric manufacturing facility to make the connections and laminators and cutting operations for form. The company has developed its own software to optimize shapes to take advantage of changing light.
“We have two technology road maps,” Cochran says. “We have one where we create our own proprietary lay-ups of encapsulating materials and manufacturing processes. The other uses existing fabrics such as Tenara® and other Gore products.”
ShadePlex uses PVC-coated vinyl for its longevity. “We have patents pending on our processes,” Tell says. “Our mission is to make solar accessible to the fabric industry—and the fabric structure industry in particular.
“Whether it’s for tents or canopies, the key differentiation of what ShadePlex does is we sell flexible solar panels with fabric mounting systems at the individual panel level, so we can sell one or 1,000 or 10,000 panels and they can be quickly and easily connected to each other and scaled to the size of the project.”
FTL and Pvilion use vinyl-coated polyester and Teflon-coated fiberglass. “We have designs for boat covers with solution-dyed acrylics like Sunbrella®. We are doing backpacks for camping with Cordura®. There are a variety of awnings, including solution-dyed acrylic and vinyl-coated polyester,” Dalland says. “We are looking to develop greener fabrics, but fabric itself is so much lighter and uses less material than alternative products.”
Photovoltaic fabric not only offers multiuse capabilities, but also aesthetic value. “I think designers will see opportunities in the variety of shapes and forms and colors,” Amon says. Additionally, she notes, the advancing technology fits today’s lifestyles. “We’re more transient, and with the idea we can produce power anywhere we need it, I see a big future for it.”
“If you embrace [this new technology], then the first benefit is that your clients now have a marketing advantage in that it’s a solar-powered product that is environmentally friendly,” he says. “A lot of my clients are starting to do this because it’s an extraordinary marketing tool to say, ‘Our company is using renewable energy.’ It indicates you are part of the solution, part of the future. Change is coming, and this is the early step.”