Solar roofing shingle and tiles blend traditional roof building techniques, PV advances and water proofing technology to essentially create a functional roof that generates electricity. But unlike big, bulky glass and metal PV panels mounted on existing roofs, solar shingles and roof tiles are seamlessly integrated into the traditional roofing style of materials.
The mix of these various disciplines result in a practical application that is the latest trend in the building-integrated photovoltaics (BIPV)market. But this marriage between the PV industry and the roofing industry is not new. In 2009, Time magazine named solar shingles as one of the top 50 inventions of the year. But that part of the BIPV market is just now taking off and the development of solar shingles and tileshave seen some recent global BIPV industry movement, particularly with recent advances in thin-film and CIGS (copper-indium-gallium-selenide) PVs.
PV Tiles and Shingles
Solar shingles utilize the same PV technology as bulky solar panels but with considerable less power output. A single PV shingle only produces between 50 and 200 watts, but several square feet of BIPV shingles together can power an entire house. Some roofing manufactures that have not been traditionally part of the PV supply chain, such as Dow Chemical, Redland and EternaTile, have recently entered the BIPV market and have designed their products to blend and be installed just like a roof shingle - hand or gun-nailed - with one simple connection to link shingle to shingle and row to row of the entire solar array to the home electrical system. These systems are designed so that if any individual solar shingle or tile fails, the entire system continues to operate.
Part of the BIPV Market
The latest generation of solar shingles is not only beginning to emerge in the marketplace after years of R&D and prototype projects, they are also factoring into the growth of the BIPV global market. Most of these BIPV opportunities are materializing in those European countries which are still offering lucrative feed-in tariffs for BIPV, while markets in North America and Asia are developing quickly.
A July 2011 report form NanoMarkets estimates that revenues in the entire BIPV product market will surpass $11 billion by 2016. The report, "Building Integrated Photovoltaics Markets, 2011," also estimates that global BIPV capacity will rise from 343 MW to 3.6 GW during the same time frame. According to the report, the revenue growth of the next generation BIPV products will include a rise from $691 million to $3 billion for the “tiles and floating panels” sector and an increase from $153 million to $1.9 billion for the “flexible products” sector.
Next Generation Product Trends
A variety of companies in the BIPV supply chain have stepped-up development and manufacturing of solar shingles and tiles. Some of the more recent developments include:
Future Building Industry Needs
Solar roofing shingles and tiles represent a unique collaboration between the building industry and the PV industry. The technical aspects of PVs can’t be expected to be developed by the roofing industry, and the roofing code standards for fire prevention as well as protection from rain, snow loads, hail and wind are beyond the work of the PV industry. But in order for BIPV solar shingles and tiles to be fully adopted by the building industry, they need to be low-cost, easy to install and meet the performance standards for roofing structures in terms of size and installation.
The market for replacing conventional roofing tiles with PV tiles or shingles has already sparked a few smaller traditional roofing companies to enter the BIPV market, following the lead of Dow.
Florida-based EternaTile is marketing a polyurethane, foam molded, interlocking solar tile that is geared to blend with a variety of roofing styles. What makes their tiles interesting is that they were developed by a roofing company which has created four styles of tiles to replace existing roofs with flat asphalt, slate, cedar shake or clay roll tiles.
Another roofing company that has gone solar is UK-based Redland. Their solar PV tile is designed to replace a single course of standard concrete or slate tiles. The company is marketing five products that integrate with eight of the company’s most popular existing roof tiles products for the home market.
The new PV shingle and tile developers are working to better take into account the needs of the building industry. One of the main concerns is the ability of a non-specialized workforce to be allowed to install these shingles and tiles during the course of the normal home construction. In the United States, for example, there are specific ordinances and tight building codes that vary from state to state that dictate which type of contractors – electrical or general - can do what type of jobs.