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Bring On BIPV Installation

Mcn  Prod Feature  Sept14 1

Tips for a safe and successful integration installation

Solar technology is advancing rapidly. Today's designs and technologies are far beyond conventional solar panel installations that had minimal aesthetic considerations. New and innovative building-integrated photovoltaic (BIPV) applications can include: solar windows or skylights, PV shingles, entire solar roofs, PV laminates and awnings. These BIPV solutions can be integrated into and onto the building envelope, often substituting photovoltaic products in place of construction materials. BIPV adheres directly to roofs without racking, reducing system weight and eliminating wind-load issues.

However, integration requires correct installation to be successful. Poor BIPV installation can result in decreased energy yields and may create fire or life safety hazards. While not comprehensive for the many diverse BIPV installations available, what follows are some standard BIPV safety advice and installation guidelines.

 

Before BIPV installation

Before installing BIPV, a roof inspection and structural analysis should be performed by a professional engineer. Contact local authorities to determine the necessary system and/or equipment grounding. Installation should be performed in compliance with the National Electrical Code (NEC), Canadian Electrical Code Part 1, OSHA and accident prevention regulations, as well as other applicable national, regional, state and local codes, and inspection requirements.

Obviously, you should also comply with the roof system manufacturer's warranty design criteria when attaching BIPCV to a roof and adhere to the BIPV manufacturer's printed installation instructions. "Prepare drawings of the building and roof layout including the location of fasteners, rooftop units and skylights," says John R. Williams, chief commercial officer, Solopower Systems Inc., Portland, Ore. "Forward drawings to your BIPV provider to prepare a preliminary layout of the BIPV system, to estimate system capacity and to assess the balance of system requirements. The BIPV provider will provide complete installation instructions for a non-penetrating PV solution. Instructions must be followed to the letter."

Conduct a BIPV pre-installation conference at the project site. During it, review the requirements of the contract documents and submittals. Usually, these are diagrammatic and establish the basic dimensions of units, sight lines and unit profiles necessary for correct and safe installation.

 

Safety and handling

Only authorized, qualified and trained personnel should have access to BIPV. BIPV installation should be performed by qualified employees with training in safe electrical and roof practices. "Installers need to receive training from the manufacturer prior to commencement of work if they have not been trained," Williams says. "An experienced supervisor should be on-site to support the installation team to ensure safety and best practices."

Many BIPV solar modules generate electrical energy when exposed to light. If not handled correctly, some BIPV modules can cause lethal shock and burns. Beware of semi-exposed live parts until installation is complete. Never touch live terminals with bare hands. Use insulated tools for electrical connections. Do not install BIPV during rain, snow or high-wind conditions. Install on a defect-free and dry roof only when the roof surface temperature is approximately between 50 F to 100 F. "The roof should be clean and wiped down with a degreaser," says Williams. Some BIPV systems can't be installed in salt air environments.

Don't install BIPV modules in lightning and electrical surge-prone areas. Don't install when laminates are wet or are in standing water. Most BIPV systems must be installed over a roof that has verifiable drainage per National Roofing Contractors Association guidelines. Don't install BIPV near roofing drains, other low areas or ponding water. During all stages of installation, prevent any type of impact to BIPV modules that could physically damage them. Do not walk or step on modules. Do not drop sharp objects on the modules and don't place heavy objects on them. This could damage the module's junction box leading to bad connections or humidity ingression.

Do not allow the module to twist or flex at any time during the shipping and installation process. Do not use different modules in the same mounting system. Do not drop BIPV modules; carry them by their frame with two or more people. Heavy modules can be lifted by suction pad devices. Do not carry a module by its wires or junction box. Do not install broken or damaged modules.

 

Direct BIPV attachment on a standing seam roof

The following list of procedures from Houston-based NCI Building Systems is specific to direct BIPV attachment panels on standing seam roofs. "Please note-the first row procedure is unique," says Bob Zabcik, director of research and development, NCI Building Systems. "All attachments are done through a two-piece clamp. The base attaches to the standing seams, and the BIPV attaches to the L-flange on the top of the clamp."

 

  1. Gather all necessary tools including a drill, tape measure, deep well socket, string line and torque wrench. Optional specialty tools include a laser and an angle driver.
  2. Determine where the first clamp will be installed. Start screw on base by hand and then tighten to recommended torque.
  3. Measure to the roof edge so you can use that measurement to install the clamp furthest away.
  4. Use a string line to line up additional clamps in the first row.
  5. Create a jig to ensure clamps are evenly spaced across roof to create a grid.
  6. Use the L-flange and the bevel guide to align the first BIPV panel.
  7. Screw an edge grab on top of both the panel and clamp to secure the panel to the roof.
  8. Use wire clips to further tighten the clamps.
  9. Lay the next BIPV panel down next to the first one and screw down a field grab to hold both panels in place. Continue this process until all panels in your grid have been installed.
  10. Make electrical connections in accordance with manufacturer instructions.

 

Peel-and-stick BIPV panels

The following procedure, also provided by NCI Building Systems, pertains to peel-and-stick BIPV panels. It is usually done in a factory setting before roofing is installed but can also be performed in the field.

 

  1. Create a cardboard template of the module, place it on the roof panel and mark the perimeter with a pencil.
  2. Pull off the paper backing of the peel-and-stick modules to expose about 2 feet of adhesive.
  3. Line up PV modules with pencil marks made in step 1 ensuring the correct end of the module is down and straight with the metal roof panel.
  4. Adhere the BIPV panels to metal roof panels by having one person apply pressure to the module while another pulls the paper backing away, working their way down the module length.
  5. Use a roller to smooth any bubbles.
  6. Install metal roof panel in the traditional way.

 

Zabcik stresses that metal roofs and metal buildings aid and impact BIPV installation in a positive way. "They are very durable, which is important because they see a considerable amount of foot traffic when a PV system is being properly maintained," he says. "Standing seam roofs have a seam every 12 to 24 inches usually, which is basically a built-in rail. That makes it ideal for either system described above, but especially the direct attachment since it eliminates the need for a rail. In contrast, on a conventional roof, you would probably have to penetrate the membrane, which require patching and would open your building up to potential leaks in the future."

Looking to the future, Ray Noble, associate at the BRE National Solar Centre based at the Eden Centre in Cornwall, U.K., predicts that as the industry moves forward, metal roof suppliers will either further integrate PV into their product or eventually the solar industry will further develop solar materials that can be integrated to the metal sheet during its manufacture.

 

Sidebar: BIPV Defined

MCN looks at how three different sources define this new technology

Building Integrated Photovoltaics (BIPV) refers to photovoltaic systems integrated within an object. It means that such systems are built/constructed along with an object. Yet, they could be built later on. According to how and where such systems are built, whether into the facade or in the roof, the following BIPV systems are recognized:

 

  • Facade or roof systems added after the building was built
  • Facade integrated photovoltaic systems built along with an object
  • Roof-integrated photovoltaic systems built along with an object
  • Shadow-Voltaic PV systems also used as shadowing systems, built along with an object or added later.

Source: pvresources dot com

BIPV are photovoltaic materials that are used to replace conventional building materials in parts of the building envelope such as the roof, skylights, or facades. They are increasingly being incorporated into the construction of new buildings as a principal or ancillary source of electrical power, although existing buildings may be retrofitted with similar technology. The term buildingapplied photovoltaics (BAPV) is sometimes used to refer to photovoltaics that are a retrofit-integrated into the building after construction is complete. Most building-integrated installations are actually BAPV. Some manufacturers and builders differentiate new construction BIPV from BAPV.

Source: Wikipedia

BIPV refers to photovoltaic modules or materials integrated with buildings as an indispensable part of the building to both generate electricity and keep off the wind and rain and insulate heat. Buildings will be deprived of such functions if the modules are removed. BIPV distinguishes itself from BAPV or simple attaching photovoltaic modules or systems to buildings in that the former functions as an integral part of the buildings like building materials. BIPV features a series of advantages such as stable electricity supply, space saving, building material saving, pro peak regulation, environment friendly and a small carbon footprint.

Source: Hanergy Holding Group