Converting Existing Carports to Solar Carports with Flexible PV Modules

Rooftop solar has become commonplace on commercial buildings and homes. Although a residential home often has sufficient rooftop area to power the home 100 percent with solar, this is not always true with multi-story commercial buildings, apartments and condominiums. The properties often do not have the necessary roof space to offset their energy needs with solar. This situation can also apply to low-rise buildings with high electrical usage, such as factories, big-box stores and warehouses.

The Miasole FLEX Series PV Modules

The Miasole FLEX Series PV Modules

Carports have become a standard feature on many commercial and multifamily properties. Even buildings without carports have parking lots with space for them. Carports provide users the benefit of shading cars and protecting cars and people from rain and snow. Carports keep cars cool, reducing the power required to air condition them when they’re started and reducing sun damage to the car finish. From an environmental standpoint, carports help migrate the heat island effect in which large concrete and asphalt parking lots absorb heat during the day and release the heat at night. This additional heat can drastically change local weather patterns, especially in metropolitan areas.

In recent years, building owners have been installing new carports with solar PV modules. These solar carports have all the benefits of traditional carports with the added advantage of producing clean renewable solar energy while reducing the need to add rooftop solar to buildings.

In many places, existing carports were designed and built with minimal steel support structures and the metal roof and deck panels are already spanning the maximum distance between supports to keep costs down. Most were built to meet the minimum local wind and live-load code requirements. With the cost of solar installations falling, utility energy costs rising and increased interest in improving the environment while reducing a building’s carbon footprint, building owners are interested in retrofitting their existing carports with solar modules. Unfortunately, many of these existing carport structures cannot support the additional 4- to 6-pounds-per-square-foot weight of standard crystalline PV modules and associated racking and rails. The only solution available to the owner is to structurally upgrade the carport or tear it down and replace it with a carport designed for the extra weight of solar. Even if the existing carport structure can support the weight, retrofitting the carport with solar can be technically challenging and expensive.

MiaSolé has developed two solar application solutions to solve the live-load limitations of many existing carports. MiaSolé manufactures a flexible lightweight high-efficiency (16 percent plus) CIGS-based flexible PV module weighing less than 9 ounces per square foot in two format sizes: the narrow-format FLEX-N series designed for traditional architectural standing-seam metal roof panels and the wide-format FLEX-W series. Both can be applied to the carport roof with a simple peel-n-stick adhesive.

Standing-seam Panel

Miasole FLEX-N on standing-seam metal panels.

Miasole FLEX-N on standing-seam metal panels.

Two roofers can easily apply the FLEX-N series to the existing carport metal panels:

  • Power wash the roof.
  • Wipe down the areas where the FLEX-N modules will be applied with rubbing alcohol.
  • On the standing-seam metal panel (16- to 18-inches wide) lay down the module.
  • One roofer lifts up the module at the j-box end, removes the release film from the adhesive and sets the module down.
  • The second roofer at the other end lifts up and supports the module.
  • The first roofer continues to remove the release film and lays down the module, rubbing the module with his hand to ensure full contact.
  • Once the module is fully adhered, both roofers use a silicone roller to bond the module to the metal pan surface.

Trapezoidal Rib Panel

Although architectural standing-seam panels are frequently used on carports, the 7.2 trapezoidal rib panel is the metal roof industry’s most commonly used corrugated roof panel for carports. Nearly every major metal roof and steel building manufacturer offers a 7.2 rib panel type profile.

The 7.2 corrugated rib panel is economical, strong and aesthetically pleasing while offering excellent spanning and cantilever capabilities, making it an excellent choice for carports and walkway canopies. The 7.2 rib panel with its long-spanning performance helps lower costs by reducing the number of purlins and structural steel needed. The ability to use long metal panels and fastening with exposed fasteners on slopes as low as 1:12 greatly reduces labor costs.

Installing the Miasole FLEX W on a 7.2 Metal panel

Installing the Miasole FLEX-W on a 7.2 metal panel.

Working with several major metal roof manufacturers such as McElroy Metal and one of the solar carport leading builders, Baja Construction, MiaSolé modified the adhesive patterns on the MiaSolé FLEX-W, the large-format PV module originally designed for low-slope single-ply roofs. The new adhesive pattern makes it simple to bond the MiaSolé Flex-W module directly across the standard 7.2 corrugated rib profile. By eliminating the need for racks and rails, the powerful 360-watt FLEX-W PV module can be rapidly installed by just two roofers over any existing carport or walkway. With a low-slope roof canopy, solar orientation—the direction the carport is facing—is less critical.

Two roofers can easier apply the FLEX-W series to the existing carport metal panels:

  • The existing carport is power washed to remove any dirt and debris from the metal roof surface.
  • Any loose panel fasteners are tightened and missing fasteners replaced.
  • The areas where the FLEX modules are to be installed are cleaned with rubbing alcohol.
  • The FLEX modules are laid down across the corrugated ribs, and the adhesive strips are aligned with the ribs.
  • On one end, the roofer lifts up the module, peels back the adhesive release film, lays the module back down on the 7.2 panel ribs and presses down to bond the module to the ribs.
  • The second roofer on the other end repeats the same process.
  • Both roofers finish bonding the module by rolling the adhesive areas with a silicone roller to ensure complete adhesion to the metal panel.

MiaSolé FLEX series PV modules make it possible to economically convert existing carports with live-load limitations into new solar carports without having to make any major structural modifications. Even on new solar carports, the MiaSolé FLEX series modules can reduce labor and construction cost by reducing the need for heavy steel support structures and allowing longer metal panels with fewer support purlins.

The peel-and-stick adhesive system reduces labor costs while speeding up installation time. Unlike conventional rigid crystalline panels, the flexible MiaSolé FLEX modules work over curved roof structures for solar carports, solar walkways and solar awnings.

MiaSolé Solar Modules Are IEC and UL Certified and Class A Fire Rated

MiaSolé's CIGS-based, thin-film FLEX-02 solar modules are IEC 61646, IEC 61730, UL 1703 certified and UL 790 Class A fire rated.

MiaSolé’s CIGS-based, thin-film FLEX-02 solar modules are IEC 61646, IEC 61730, UL 1703 certified and UL 790 Class A fire rated.

MiaSolé announces that its CIGS-based, thin-film FLEX-02 solar modules are IEC 61646, IEC 61730, UL 1703 certified and UL 790 Class A fire rated. The MiaSolé FLEX module is a high-efficiency flexible, lightweight thin-film solar module, with production efficiencies of 16 percent. The FLEX module provides high power density for many types of applications—from roofing to reservoir and landfill covers, to auto, truck and other transportation applications through off-grid and consumer applications. The FLEX modules are produced in high volume at MiaSolé’s Heyuan, China, factory, which has passed UL, IEC and ISO9001 qualifications.

FLEX-02 modules provide customers significant benefits. The low weight of the module (less than 0.7 pound per square foot) allows installation on roofs and other structures that cannot support the weight of traditional glass solar panels. Because the FLEX-02 modules adhere directly to the surface of the structure or object, there are no penetrations or damage. The FLEX-02 is also aesthetically pleasing, blending into roofs, vehicles and other structures and preserving the original look without unsightly racking. The low-profile FLEX-02 module provides wind resistance and a seismic advantage over traditional rack-and-panel systems where their higher profile increases the likelihood of damage in a hurricane or earthquake.

Midsummer Receives Loan for Production of Flexible Thin Film Solar Cells

The Swedish solar energy company Midsummer, a provider of equipment for cost-effective production of flexible thin film solar cells, receives a loan of 10 million SEK from the regional development agency Almi Företagspartner Stockholm Sörmland AB.

The Swedish solar energy company Midsummer, a provider of equipment for cost-effective production of flexible thin film solar cells, receives a loan of 10 million SEK from the regional development agency Almi Företagspartner Stockholm Sörmland AB.

The Swedish solar energy company Midsummer, a provider of equipment for cost-effective production of flexible thin film solar cells, receives a loan of 10 million SEK from the regional development agency Almi Företagspartner Stockholm Sörmland AB. The loan is meant to support Midsummer’s focus on production and sales of the DUO machines used for the production of flexible thin film solar cells.

Midsummer is a supplier of equipment for cost-effective production of flexible CIGS thin film solar cells. Midsummer’s turnkey production lines are compact, fully scalable and enable small-scale production of solar cells and modules.

Swedish regional development agency Almi Företagspartner AB has now decided to grant Midsummer a loan of 10 million SEK, part of which is guaranteed by the European Investment Fund, EIF. The purpose of the investment loan is to provide Midsummer with increased resources for research and development of machinery for the production of thin film solar cells, known as DUO machines.

“Our loan intends to provide opportunity for innovative companies to develop innovations and business ideas that provide growth and profitability,” says Fredrik Larsson, financial advisor, Almi Företagspartner Stockholm Sörmland AB.

“We sold a DUO system this spring to a foreign multinational company, which is yet another proof of the market potential for our system,” says Sven Lindström, CEO, Midsummer. “The DUO is a compact, fully automated system for production of CIGS solar cells. It is designed for high productivity, operational stability and superior material utilization.”

Midsummer’s customers are manufacturers of flexible thin film solar cells worldwide. An increasing number of companies see the benefits of the technology as it can be easily integrated in buildings (BIPV)—a rapidly growing segment.

Fredrik Larsson continues: “Through the funding we hope to provide Midsummer with the opportunity to develop and pursue its commercialization. It is hoped that Midsummer can become a model for other Swedish environmental technology companies. It will be interesting to follow the company on its journey.”

Midsummer is one of Sweden’s high-profile technology companies and has, among others, been named as one of Sweden’s hottest incubator companies (Almi). Midsummer has been named as one of Sweden’s hottest technology companies and also been repeatedly featured on the list of the nation’s fastest growing technology companies. Midsummer was the fastest growing cleantech company in the EMEA region in 2007-11 (Deloitte, Fast 500).

Almi Företagspartner AB’s vision is to create possibilities for all viable ideas and businesses to develop. Almi provides counseling, debt and equity in the enterprise all phases—from ideas to successful businesses. Almi Företagspartner AB is owned by the state.

The European Investment Fund, EIF supports the growth and development of small and medium enterprises. EIF’s founder members are the European Investment Bank (EIB), the Commission and private European financial institutions.

Flisom Receives Investment from Tata Group for Thin-film Solar Module Production Plant

Flisom, a Swiss company developing innovative technologies for manufacturing of flexible thin-film CIGS solar modules (copper-indium-gallium-(di)selenide), has received an additional investment of CHF 10 million following an earlier investment of CHF 42.5 million in 2013 for the pilot production plant with an annual capacity of 15MW in Niederhasli-Zurich in Switzerland. During the last years, Flisom improved the design of roll-to-roll manufacturing machines for processing and scaled them up from 50-centimeter-wide to 1-meter-wide rolls—an unprecedented scale of manufacturing capability for continuous processing of cost-efficient, high-performance monolithically interconnected flexible CIGS solar modules on plastic foil.

This fourth round of funding comes from Flisom’s existing strategic investor, the Tata group, a global enterprise headquartered in India. “We are very pleased with this further investment from the Tata group coming on the eve of the inauguration of Flisom’s 15 MW capacity pilot production plant, and we thank the Tata group and existing investors for their continued support,” says Ayodhya Nath Tiwari, chairman of Flisom Co.

“We appreciate the systematic approach towards innovation and the continuous hard work of Flisom’s team in developing a unique manufacturing plant, while partnering with Empa with several efficiency-related records for flexible solar cells,” says K.R.S. Jamwal, executive director, Tata Industries. He adds, “This investment marks Tata group’s interest in next-generation technology for the solar photovoltaic industry.”

“With the investment received in 2013, Flisom refurbished an old manufacturing building of 4,500-square-meter ground area in Niederhasli, in the outskirts of Zurich, to install all the needed machines for solar module manufacturing on 1-meter-wide rolls. At the same time, Flisom continued technology development on 50-centimeter-wide rolls at its Dübendorf plant, located on the campus of Empa,” says Flisom’s COO, Sudheer Kumar.

The CEO of Flisom, Ulfert Rühle says: “After the successful installation of machines and other factory infrastructure in Niederhasli, the next step is to transfer the process know-how on these high-tech machines using specifically customized designs. Some of the machines are based on many years of development by experts, innovative proprietary designs and complex engineering making Flisom’s machines unique for achieving cost and performance efficiency targets for a breakthrough manufacturing”.

“The 15MW plant will serve as a proven blueprint for establishing larger production plants having a production capacity greater than 100 MW as well as low capital and operating expenditures. Flisom has been working steadily towards lowering the costs of manufacturing of flexible solar modules,” adds CEO Rühle.

Flisom’s high-performance, lightweight, and robust products and systems could lower the price of solar electricity thanks to low material usage, economic production technology, and reduced storage, transportation and installation costs. Markets addressable by Flisom’s flexible solar module manufacturing technology include utility scale solar farms, building integrated photovoltaics (BIPV), building applied photovoltaics (BAPV), transportation and portable power.

Ayodhya N. Tiwari, founder of the ETHZ spin-off company Flisom and the head of the Laboratory for Thin Films and Photovoltaics, Empa-Swiss Federal Laboratories for Material Science and Technologies, believes that the high-efficiency flexible and lightweight CIGS thin-film solar cells have great potential to provide low-cost installed solar systems, bringing many beneficial features together in a very unique manner. In addition to the economic benefits, CIGS thin-film solar modules, known for faster energy payback than the mainstream Si wafer technology, will significantly contribute to CO2 reduction. Future norms and regulations are expected to enforce application of carbon footprint reducing technologies. Therefore, the broad range of applications of flexible lightweight CIGS modules, especially in buildings, will open up untapped markets worth several billion euros while advantageously reducing carbon footprint. This goal is achievable with highly efficient, long-term performance stable, low-cost solar modules produced in a low-capex production plant.

Empa and Flisom have been cooperating for a number of years to develop a unique industrial-scale production platform for CIGS thin-film solar modules. “Scale-up for large-area solar modules and adapting these complex innovative processes for industrial manufacturability is quite a challenge and requires close collaboration between research labs and industrial partners for transferring research excellence to industrial usability,” says Pierangelo Groening, head of the Department of Advanced Materials and Surfaces and member of Empa’s Board of Directors. ”For industrial partners such as Flisom, we provide support on different topics to enable industrial development of novel and innovative concepts, which often require sophisticated analytical tools and skilled experts.” Empa CEO Gian-Luca Bona adds: “We are pleased that Empa’s innovations in the field of renewable energy, especially in photovoltaics, are being transferred to industry for the benefits of a more sustainable society with a growing energy demand. This example perfectly illustrates Empa’s role as a bridge between research and practical applications.”

“Flisom is thankful to Empa for very valuable and sustained research and development support over several years. Flisom also thanks Swiss federal and European funding agencies for their continuous support. Besides the technological progress, the number of employees during the last two years have gone up to more than 55 now, and of course more employment opportunities for technically skilled persons are open for the production plant in Niederhasli,” says Flisom CEO Ulfert Rühle.

Thin-film PV Provides Greater than 16 Percent Cell Efficiency

MiaSolé has made available its second-generation FLEX Series Modules.

MiaSolé has made available its second-generation FLEX Series Modules.

MiaSolé has made available its second-generation FLEX Series Modules. The CIGS-based flexible thin-film PV modules provide greater than 16 percent cell efficiency for many types of roof applications. FLEX-02W module is 39 by 102 inches, rated at 360 watts and designed for low-slope commercial single-ply roof systems. FLEX-02N module is 14.6 by 102 inches, rated at 120W and designed for standing-seam metal roofs. Both modules bond to the roof surface with a simple peel-and-stick adhesive, which eliminates the need for racking and reduces labor and logistics costs. The FLEX-02 Series modules are IEC 61646, IEC 61730 and UL 1703 certified.

Large Format Solar Module Is for Low Slope Commercial Roofing

Miasole FLEX W module

Miasole FLEX W module

Miasole, a company of Hanergy, introduces its new FLEX 01-W PV (210-watts) module for TPO roof systems. The Miasole FLEX W module is the roofing industry’s first flexible large format solar module for low slope commercial roofing. The FLEX module’s high-performance self-adhesive provides a roofer-friendly simple peel-n-stick installation system with the industry’s first 25-year adhesion guarantee.

The Miasole FLEX module bonded to the TPO roof systems eliminates the need for racking, concrete ballast or roof penetrations. The FLEX low profile PV module has the same wind uplift rating of the roof system design, making FLEX the best solar choice for high wind zones. Weighting less than 0.7 pound/square feet, FLEX is idea for roofs with low load capacity and buildings in high seismic areas.

The Miasole FLEX modules simplify project logistics, reduce labor costs and installation.

View the Miasole solar TPO installation video.

MiaSolé is a producer of thin-film Copper Indium Gallium Selenide (CIGS) solar cells and panels. Founded in 2004, MiaSolé has evolved from a Silicon Valley start-up to the world leader in thin film solar panel efficiency. In its Sunnyvale, Calif., facility, MiaSolé has demonstrated 15.5 percent module efficiency in production. Miasole became part of the Hanergy family of renewable energy technology companies in 2012.

Solar Roof Energy Is the Answer for Mega Cities of the Future

Seven billion people will live and work in urban areas by 2050 and the demand for energy for all these people will be huge. Local production of energy will be needed with building-integrated photovoltaics (BIPV) key to make cities at least partially self-sufficient with energy. Rapid development in thin-film solar cell efficiency strengthens the business case for BIPV with great opportunities for suppliers of roofing materials and construction companies.

The electricity produced by ‘roof solar energy’ could be used for heating, cooling, running office machinery or even fed back to the grid, earning the building owners money.

The electricity produced by ‘roof solar energy’ could be used for heating, cooling, running office machinery or even fed back to the grid, earning the building owners money.

More than half of the planet’s population lives in urban regions today. This will grow to 75 percent in the next 30 to 35 years. That would mean 7 billion people living in more or less congested areas, all needing shelter, food—and lots of energy.

There is a growing consensus that the mega cities in the future cannot rely entirely on energy produced far away. Besides supply constraints, there are energy losses in the transport of the electricity; logistical nightmares; security issues; and, of course, environmental concerns.

There is a very healthy debate about distributed energy generation, often defined as electricity generation from many small sources. This discussion must be encouraged. We simply cannot solve the energy challenges of tomorrow with energy solutions of yesterday.

The distributed energy discussion has so far mainly centered on local smaller power plants, district energy, more efficient electricity distribution, the ‘smart grid’, etc. That is good. But we must also talk about the potential for local production of renewable energy by the end users on a micro scale, the very individuals who consume all this energy.

What do the end users have in common? Well, they all need a roof over their heads, at home and at work. These roofs can produce renewable energy! So the building industry can play a major role in solving mega cities’ energy challenges.

Building-integrated photovoltaics can be incorporated into the construction of new buildings as a principal or ancillary source of electrical power, and existing buildings may be retrofitted with similar technology.

Building-integrated photovoltaics can be incorporated into the construction of new buildings as a principal or ancillary source of electrical power, and existing buildings may be retrofitted with similar technology.

Look at an aerial image of a city and you will see an area densely covered by buildings—crisscrossed by roads and the occasional recreational area. All these buildings—houses, apartments, garages, offices, factories, schools and municipal buildings of all sorts—have roofs. New development in solar energy has transformed all these roofs—and even walls—into potential giant solar energy receivers.

The electricity produced by ‘roof solar energy’ could be used for heating, cooling, running office machinery or even fed back to the grid, earning the building owners money.

What I call ‘roof energy’ is building-integrated photovoltaics (BIPV), one of the fastest-growing segments of the photovoltaic industry. Photovoltaic materials are used to replace (or are added onto) conventional building materials in not only roofs, but also skylights and facades. They can be incorporated into the construction of new buildings as a principal or ancillary source of electrical power, and existing buildings may be retrofitted with similar technology.

Traditional wafer-based silicon solar cells are efficient but rigid, thick and heavy, ideal for large solar parks in sparsely populated areas but not in dense cities. They are too heavy for most roofs. However, thin-film solar cells made out of a copper-indium-gallium-selenium metal alloy (CIGS) are thin, light and flexible. They can be made frameless, can be bent, and are ideal for buildings and other structures that are uneven, moving or weak.

The business case for thin-film solar cells is strengthening rapidly since they are becoming increasingly efficient. A Swedish supplier of thin-film solar cell manufacturing equipment has managed to increase the aperture efficiency (the area on the solar panel that collects energy) from 6 percent four years ago to 11 percent two years ago and a record breaking 17 percent today by using a revolutionary all-dry, all vacuum process where all layers are deposited by sputtering.

An office, school, storage facility or factory with a flat roof in a Mediterranean country like Italy could annually yield 1,250 kWh from every kW installed, at a production cost of 7.2 U.S. cents. The production cost would decrease if the roof is slanted by up to 20 percent for an optimal 35-degree angle. The production cost would obviously be higher in colder countries and lower in countries nearer the equator. But even in Sweden the production cost could be as low as 8 cents.

Thin-film solar cells made out of a copper-indium-gallium-selenium metal alloy (CIGS) are thin, light and flexible.

Thin-film solar cells made out of a copper-indium-gallium-selenium metal alloy (CIGS) are thin, light and flexible.

A production cost of 5 to 10 cents is well below the current—not to mention the expected future—electricity prices. There are great variations in the price of electricity today, but many users pay between 10 and 30 cents per kWh (including taxes). Commercial and residential users pay even more.

The $100bn global roofing material market is in a healthy state, growing at 3.7 percent per annum and driven by an uptick in residential building construction (especially reroofing) in developed and developing markets. Here is an excellent opportunity for architects, roofing material suppliers and construction companies to take a leading position in what is destined to be the material of choice for urban planners in the future.

Thin-film BIPV solar energy solutions can be made light and are flexible. They can be fitted or retrofitted onto roofs without perforating the roofs and can be curved or bent. Installation is easy and cost-efficient with no racks or ballast needed. There are no weight constraints and no access limitations (you can walk on the panels). And they can be integrated on bitumen and TPO membranes.

Selling roofing solutions and electricity together opens up to completely new business models: suppliers can offer a discounted roofing price in combination with a stable and independent supply of electricity. Customers can secure electricity price—and get a new roof.

Municipalities and city planners in today’s and tomorrow’s mega cities will make efforts to make their cities greener and more sustainable. It is no wild guess that green buildings with ‘roof energy’ systems will get preferential treatment in public tenders and maybe even subsidies. Building owners will like the prospect of lower energy costs.

So the question to the world’s architects, roof manufacturers and construction companies is: Do you feel lucky? Do you feel confident enough to keep doing business as usual, selling traditional roofs to consumers who might sooner than expected demand energy-producing and cost-saving roofs and buildings? Or will you grab an unparalleled opportunity to gain market share by offering state-of-the-art products that will change the world or at least the way the world’s urban population powers their daily lives?

For me, the answer is simple: If end users can produce part of the energy consumed in a sustainable fashion where they live and work, that would go a long way toward solving the energy and climate challenges of the future. Flexible, efficient, thin-film solar cells for buildings are an integral part of this solution.