Building-Integrated Photovoltaics (BIPV)

Contents

Building-Integrated Photovoltaics (BIPV) refers to the integration of photovoltaic materials directly into the building’s architecture, replacing conventional building materials in parts of the building envelope such as the roof, skylights, or facades. BIPV systems not only generate electricity but also serve as building components, providing aesthetic, functional, and financial benefits. Photovoltaic products designed to form an integral part when a building or part of a building is made (rather than just added to an existing structure) began to become commercially available in the 1990s.

BIPV

Key components of BIPV systems

Photovoltaic Modules

These modules convert sunlight into electricity, which can be used on-site or fed into the grid. BIPV modules come in various forms, including solar panels, solar shingles, solar tiles, and solar glazing units.

Inverters

The inverters convert the direct current (DC) electricity generated by the photovoltaic modules into alternating current (AC), which is used in buildings.

Mounting Systems

BIPV modules are integrated into the building’s structure, serving dual purposes as building materials and energy generators. There are many different mounting systems available, such as mounting systems for roofs, facades, and windows.

Energy Storage Systems (Optional)

Batteries can be used to store excess electricity generated during peak sunlight hours for use during periods of low sunlight or at night.

Applications

Roofs

  • Solar Shingles and Tiles: Replace traditional roofing materials with photovoltaic shingles or tiles that generate electricity.
  • Roof Panels: Large photovoltaic panels integrated into the roof structure.


Facades

  • Solar Facades: Photovoltaic panels integrated into the outer walls of buildings, providing energy generation and aesthetic appeal.
  • Curtain Walls: Glass facades embedded with photovoltaic cells.


Windows and Skylights

  • Solar Glazing: Windows and skylights with embedded photovoltaic cells that generate electricity while allowing natural light into the building.
  • Transparent PV Glass: Specially designed glass that maintains transparency while generating power.

Solar shingles

One example of a well-known type of BIPV is the solar shingle, also known as a photovoltaic shingle. These shingles are designed to both look and function as roof shingles, while also producing electricity. Functionally, they can replace other common shingle types, such as asphalt single or slate. They are thus not intented to be installed on top of classic shingles – they are installed instead of them.

Most (but not all) solar shingles contain monocrystalline or polycrystalline silicon solar cells.

History

Mass-produced solar shingles became commercially available in the mid-2000s, but did not become common until the 2010s. One notable step towards them being more readily available was taken in 2011, when Dow Chemical Company released their Powerhouse Solar System in Colorado. Later, a third-generation Powerhouse Solar System was licensed to RGS Energy for commercialization in 2017-2020.

Another notable milestone was reached in 2016, when Tesla and SolarCity formed a joint venture and entered the solar shingle market together. Eventually, SolarCity became a part of Tesla.

In early 2022, GAF Materials Corporation announced their entry into the solar shingle market.

Examples of solar shingle types

  • Shingle-sized solid panels. One such panel will take the place of one classic shingle.
  • Semi-rigid designs with silicon solar cells.
  • Thin-film solar cell solutions that are very similar to classic shingles in both size and flexibility.

Exposed surface

A majority of the commercially available solar shingles are 12 inches x 86 inches (30 cm x 21,8 cm) and are designed to be stapled directly to the roofing cloth. The exposed surface will, of course, be smaller, since that is how shingles are layed. A standard 12 in x 86 in solar shingle will typically have a 5 in x 86 in strip of exposed surface when applied. Of course, this is not the case for every possible solar shingle out there – the dimensions will depend on the manufacturer and the mounting requirements.

Mixed roofs

Some solar shingles are designed in a way that makes it possible to use them intermixed with classic asphalt shingles.

Look

Most of the commercial available solar shingle roofs are black or of a deep, dark purplish colour.

Price

Solar shingles are usually more expensive to get compared to traditional solar panels. In the United States, one could expect to pay at least $20,000 for 350 solar shingles for a standard residential single-family building in the late 2010s. When comparing prices, make sure you look into any applicable federal and state incentives which can reduce the final cost to the homeowners.

Solar shingles for residential buildings are typically purchased as a package deal that includes both the equipment and the on-site installation work. There are also companies that will include the cost of permit filing and registration with a local utility company (when applicable).

Manufacturers

Examples of well-known manufactorers of solar shingles:

  • CertainTeed makes the Apollo II solar shingle.
  • SunTegra makes the SunTegra shingle.

Benefits of BIPV

  1. Energy Efficiency and Cost Savings
    • Reduced Energy Bills: Generate a significant portion of a building’s electricity needs, reducing reliance on grid power and lowering energy bills.
    • Incentives and Rebates: Eligible for various government incentives, tax credits, and rebates, which can offset the initial installation costs.
  2. Aesthetic Integration
    • Seamless Design: BIPV systems blend seamlessly with building architecture, providing a modern and aesthetically pleasing appearance.
    • Versatility: Available in various colors, shapes, and sizes to match different architectural styles and requirements.
  3. Environmental Impact
    • Sustainability: BIPV systems harness renewable solar energy, reducing carbon footprint and greenhouse gas emissions.
    • Green Building Certification: Contribute to achieving green building certifications such as LEED (Leadership in Energy and Environmental Design).
  4. Functional Benefits
    • Weather Protection: BIPV materials provide weather protection, thermal insulation, and noise reduction, similar to conventional building materials.
    • Durability: High-quality BIPV modules are designed to withstand harsh weather conditions, ensuring long-term performance and durability.

Challenges and considerations

  1. Initial Costs
    • High Installation Costs: BIPV systems can have higher upfront costs compared to traditional photovoltaic systems and building materials.
    • Return on Investment: Long-term savings and incentives can offset initial costs, but the payback period may vary.
  2. Design and Integration
    • Architectural Design: Requires careful planning and collaboration between architects, engineers, and solar specialists to ensure proper integration.
    • Building Codes and Standards: Must comply with local building codes, standards, and regulations for both photovoltaic systems and building materials.
  3. Performance and Efficiency
    • Orientation and Shading: The performance of BIPV systems depends on the building’s orientation, shading, and local climate conditions.
    • Technological Advances: Continuous advancements in photovoltaic technology are improving the efficiency and cost-effectiveness of BIPV systems.

Future of BIPV

  • Technological Innovation: Ongoing research and development are leading to more efficient, cost-effective, and aesthetically versatile BIPV materials.
  • Market Growth: Increasing demand for sustainable building solutions and renewable energy sources is driving the growth of the BIPV market.
  • Integration with Smart Grids: BIPV systems are expected to play a significant role in smart grid technologies, contributing to decentralized and resilient energy systems.

Final thoughts

Building-Integrated Photovoltaics (BIPV) offer a forward-thinking approach to sustainable building design, combining functionality, aesthetics, and energy efficiency. By integrating photovoltaic materials into the fabric of buildings, BIPV systems provide a practical and attractive solution for harnessing solar energy, reducing environmental impact, and achieving energy independence. As technology continues to advance and the demand for green building solutions grows, BIPV is poised to become an integral part of modern architecture and urban planning.