New Opportunities For The Roofing Industry In Solar
By KC CHANG, SANYO Canada Inc.

With the introduction of Ontario’s new Feed-In Tariff (FIT) program in June 2009, as part of the Green Energy Act (Bill 150), there is a tremendous opportunity for both traditional and non-traditional players in this emerging renewable energy generation market. This article is intended to provide the roofing industry with an introduction to solar photovoltaic (PV) systems, and to help the roofing industry participate in this high growth market.

INTRODUCTION TO SOLAR PV
There are various renewable energy sources available today which include solar, wind, water, biomass, biogas and others. Since this article is an introduction to solar, the discussion is limited to solar. There are two main types of solar systems based on the way they convert the sun’s energy: Solar PV and solar thermal. Solar PV systems convert the sun’s energy into electricity whereas solar thermal systems typically convert sun’s energy into heat.

This article focuses only on solar PV systems. Furthermore, the information is limited to grid-connected solar PV systems, which are different than off-grid, or stand-alone systems.

An off-grid or stand-alone system typically utilizes the solar PV modules to charge a bank of batteries to store the energy for later use. This type of system is used for back-up power, or in remote locations where there is no access to grid power.

A grid-connected solar PV system consists of various components as shown in Figure One.

Although the figure shown is a typical residential system, systems on commercial or industrial building rooftops have the same configuration. The main components are solar PV modules and inverter(s). A solar PV module consists of a number of solar cells interconnected in strings and packaged in a tempered glass and aluminum frame. A typical solar PV module is shown here(1).

An inverter is a unit that converts DC electricity from the solar PV modules into AC electricity to be compatible with existing AC electricity used in homes and businesses.

The performance of a solar PV system depends on various components in the system, but the major factor is the efficiency of the solar cells in the PV modules. A number of different solar cell technologies are available today, mono crystalline, poly-crystalline and amorphous cells, as well as emerging thin film technologies. However, a majority of the systems in the solar PV market today utilize solar PV modules based on either mono or poly crystalline solar cells. The main reasons for the popularity of crystalline solar cell-based modules are i) their efficiency is higher than thin film technologies resulting in a higher energy being generated; ii) the product is more mature than thin film. Hence, crystalline solar cell-based modules have been proven in the field and are more widely available. Thin film technology is relatively new and there is not as well-proven or available. Major differences between silicon wafer solar cells (mono or poly-crystalline cells) and thin film technology are highlighted below.

Silicon wafer cells have efficiencies of up to 20.2 per cent (2) for mono-crystalline solar cells or 13 to 16 per cent for poly-crystalline solar cells compared to only six to eight per cent for thin films. However, thin films have relatively lower cost and weight less than crystalline solar cell-based PV modules.

WHAT ARE THE BENEFITS OF SOLAR PV?
Solar power is 100 per cent clean and is an unlimited resource unlike fossil fuel or nuclear, and hence does not create pollution that is harmful to the environment. It is available almost anywhere in the world. It is ideal for generating electricity I urban areas where the need is greatest – i.e. as distributed generation, which avoids costs associated with transmission from central generating stations. It almost always perfectly matches peak electricity requirements during the day – Solar PV systems generate the most electricity during a hot summer day when air conditioning units are running at the maximum capacity, for example.

Furthermore, solar PV systems are noise-free since there are no moving parts, and require minimal maintenance unlike other distributed generation such as wind turbines. PV is also scalable and portable since the system can be designed to be modular and can sit on removable, ballasted roof mounts.

On most practical terms, solar power reduces electricity costs. In addition to virtually free electricity from the solar PV system, one can take advantage of various government incentive programs to further reduce electricity costs at homes and businesses. As mentioned above, in the province of Ontario, under the Feed-In Tariff program, the government will pay up to 80.2 cents/kWh for electricity generated using a small scale solar PV system for a contracted period of 20 years.

The table in Figure Two provides the proposed price schedule for solar PV systems that feed electricity into the grid.

Based on the rates in Table One, the solar PV system owner can generate FIT revenue which may be applied to reduce expenses related to electricity consumption. The following table provides an outline of potential FIT revenue based on the total size of the system.

Solar power helps to protect the environment. Solar power is 100 per cent clean energy. It protects the environment and the community by helps to reduce harmful GHG (Greenhouse Gas) emissions and decreasing reliance on fossil fuel power plants.

There is a sense of gratification that comes with adding a solar PV system to a home or business, since it demonstrates the owner’s commitment to become an environmentally and socio-economically-responsible individual and/or corporation by providing a positive contribution in protecting the environment and the Earth for future generations to enjoy. It is also a valuable public relations tool for any corporation.

HOW DOES A SOLAR PV SYSTEM WORK?
When sunlight strikes a solar panel, it excites electrons trapped in the silicon solar cell. The electrons travel through wires on the back of the solar panel and into the house or building, to be used immediately or to be sent to the electric grid.

There are different ways of mounting solar PV modules, but two main types are most widely used: Fixed mounts or tracking systems. In a fixed system, the modules are fixed to a support structure, typically at an angle of Latitude minus 10 degrees for maximum annual exposure to sunlight. The angle is a compromise between the ideal for summer and winter season. The panel ideally faces directly south. A variation of this mounting option is a seasonally adjustable mounting scheme where the angle of the models can be manually adjusted for summer and winter season to further increase exposure to sunlight.

The other method of mounting the modules is a tracking system where the PV modules track the sun. This maximizes the panel’s surface area exposed to the sun, and optimizes the energy harvest. The system can be designed to be a single axis tracker (modules follow the sun in one axis only) or a dual axis tracker (modules follow the sun in both x and y axis). The dual axis tracking system generates the most energy because the PV modules have the most surface area exposed to the sun each day compared with the other methods. However, the initial cost of the tracking systems is higher than fixed system. In addition, periodic maintenance may be required to minimize failures due to moving components being introduced into the system/

Fixed systems can be installed on the ground using a support structure or poles, or on rooftops, both flat and sloped. However, the majority of tracking systems today are installed on a pole on the ground.

To highlight and track energy generation from solar PV, a typical installation integrates a monitoring system. The monitoring system collects relevant data such as total energy generated, peak output power, irradiation, ambient temperature and module temperatures, wind speed, etc., for performance analysis. The data can also be converted to provide other parameters like carbon offsets, which highlight the system’s contribution to protecting the environment. This data can be integrated into a public relations effort.

OPPORTUNITIES FOR THE ROOFING INDUSTRY
With the advent of the FIT program in Ontario, and a higher FIT rate for rooftop solar PV systems, the roofing industry has a huge potential to lead the rooftop solar PV systems market. It is a great opportunity for the roofing industry to increase its value in the roofing market with relatively little effort.

There are two main types of rooftop systems based on whether the system requires roof penetrations or not. As one can imagine, there are major implications associated with the systems that penetrate the roof – i.e. roof warranty. To overcome this challenge, traditional system integrators typically use ballasted systems that require no penetration on the roof. A ballasted system secures the solar PV system by weighing it down with concrete blocks. Even this type of system, in the long run, may potentially cause damage to the roof if it is not designed and installed properly.

In a properly designed system with appropriate system components for a specific rooftop, the installation is a relatively simple extension of the roofing work. A typical installation consists of erecting a support structure by securing the steel or aluminum metal support structure onto the roof, roofing around the support structure where necessary, and then securing PV modules to the support structure. The remaining work consists of electrical connections performed by a certified electrician.

Since most traditional solar PV system integrators do not have working knowledge or expertise in roofing, roofing professionals bring the value of their expertise to the PV integrator. In addition, since the installation is a relatively simple extension of roofing work, and can be performed in conjunction with the actual roof replacement, it benefits both the roofing professional and their client by optimizing resources and time.

The other advantage that the roofing industry can leverage is their access to the existing customer base of commercial, institutional and industrial building owners/managers. Again, the promotional effort for a solar PV system is relatively simple because the roofing professional already has an easy access to the existing customer base. The customer base already has a well-established relationship with each roofing professional with proven performance. The building owner is more likely to work with a roofer who can offer solar, and a solar integrator who can offer roofing, than either of the two on their own.

BENEFITS FOR CUSTOMERS
There are many benefits of installing rooftop solar PV systems. First is the financial benefit. With a FIT contract, a typical rooftop solar PV system in the 10- to 25-kW capacity range has a simple payback period of less than 10 years. If the customer can leverage the federal government’s Capital Cost Allowance (CCA 43.2) to write-off the capital cost associated with the system, then the payback period may be as short as four to five years. CCA 43.2 allows a system owner to write-off the total capital cost at 50 per cent every year on a declining balance. Hence, the majority of the capital cost may be written-off within three to four years depending on the system owner’s tax level. Since the FIT program contract is 20 years, there is a constant revenue stream for the remaining years after the payback period at the rate shown in Table One.

Although owning a solar PV system outright is one option, other options are available that ease the initial burden of outlaying a large capital expense. Some options are: System leasing, power purchase agreements and co-ownership. For more information on the options, please contact AMP Solar Group (www.ampsolargroup.com ).

Second is the public relations value. Installing a solar PV system clearly demonstrates a customer’s commitment to become environmentally- and socially-responsible. This powerful message can increase market exposure, which may result in higher sales, a higher number of visitors, etc., depending on its business activity.

Third is a reduction in the building’s energy profile, and reduced maintenance. The rooftop solar PV system acts as a shade for the building with the added benefit that the PV modules absorb some heat, reducing the heat build-up in the building. In turn, electricity consumption in the summer time is reduced by reducing the air conditioning load. In addition, the roof membrane is protected from the harmful UV rays from the sun, which is another benefit of the shade they provide. As a result, roofing maintenance and/or replacement requirements are reduced.

SUMMARY
The Feed-In Tariff (FIT) program in Ontario is becoming a catalyst to kick-start the solar PV market. It is poised for rapid growth attracting various players including non-traditional solar PV players. The FIT program is designed to make solar PV into a viable investment vehicle. As evident in the FIT rate structure, the program encourages distributed generation in urban areas through rooftop solar PV system installations.

The roofing industry has an immediate opportunity to enter a market with a tremendous potential to expand and to increase its value with minimum investment and resource. Due to limited expertise in working with commercial roofs by traditional solar PV professionals, roofing professionals have distinct advantages over these players in actively participating in the system installation by combining the installation with the roofing work itself. In addition, roofing professionals can now reach out to their existing customer base to promote rooftop solar PV systems wince the majority of customers would have the most critical asset required for a solar PV system: a flat roof on a building that the roofing professionals “own.”

The future looks bright for the solar PV market in Ontario. The roofing industry has the necessary expertise and customer base to take the lead in the rooftop solar PV market in Ontario.

For more information, please contact KC Change – This e-mail address is being protected from spam bots, you need JavaScript enabled to view it - at Sanyo Canada.

FOOTNOTES
  (1)  SANYO HIT (Heterojunction with Intrinsic Thin Layer) Power N PV Module.
  (2)  SANYO HIT Solar Cells.
  (3)  Based on SANYO HIT power N 210W PV Module.
  (4)  Based on RETScreen energy model with SANYO 210W PV Module at 30 degrees facing south.
  (5)  Based on RETScreen energy model with SANYO 210W PV Module near the Toronto Airport at 30 degrees facing south, all energy generated exported to the grid.