What is Building-Integrated Photovoltaics (BIPV)?

Building-integrated photovoltaics (BIPV) refer to solar power generation products or systems that are harmoniously incorporated into the building structure, specifically within components like façades, roofs, or windows. With a dual role, BIPV systems function as essential elements of the building envelope by efficiently converting solar energy into electricity, while also fulfilling various building envelope functions such as:

• Offering weather protection (including waterproofing and sun protection)
• Providing thermal insulation
• Ensuring noise reduction
• Facilitating daylight illumination
• Enhancing safety measures.

Design Of a Building Integrated Photovoltaics (BIPV) System

When considering BIPV systems, it is important to adopt energy-conscious design techniques and carefully select and specify equipment and systems. Instead of focusing solely on the initial expenses, BIPV systems should be evaluated based on their life-cycle costs, taking into account the potential savings from reduced building materials and labor. Designing BIPV systems requires considering factors such as the building’s purpose and electrical demands, its location and orientation, compliance with building and safety codes, as well as utility-related considerations and costs.

Steps in designing a BIPV system include:

1. Give careful consideration to implementing energy-conscious design practices and energy-efficiency measures to reduce the building’s energy requirements. This not only enhances comfort and cost savings but also allows the BIPV system to make a more significant contribution to meeting the energy demand.

2. Choose Between a Utility-Interactive PV System and a Stand-alone PV System:

  • Most BIPV systems are connected to the utility grid, utilizing it for storage and backup. The sizing of these systems should align with the owner’s goals, typically driven by budget or space constraints. Additionally, the selection of the inverter should be based on understanding the utility’s requirements.
  • In stand-alone systems that rely solely on PV power, it is necessary to size the system, including storage, to meet both the building’s peak energy demand and the lowest projections of power production. To prevent over-sizing the PV/battery system for infrequent or unusual peak loads, a backup generator is often integrated. This hybrid system, combining PV and a generator, is commonly known as a “PV-genset hybrid”.

3. Evaluate the use of hybrid PV-solar thermal systems: To optimize system efficiency, designers may consider capturing and utilizing the solar thermal resource generated through the heating of the PV modules. This approach can be attractive in cold climates for pre-heating incoming ventilation make-up air.

4. Explore the integration of daylighting and photovoltaic collection: By utilizing semi-transparent thin-film modules or crystalline modules with custom-spaced cells between layers of glass, PV can be used to create unique daylighting features in façades, roofs, or skylight PV systems. These BIPV elements can also help reduce unwanted cooling loads and glare associated with extensive architectural glazing.

5. Incorporate PV modules into shading devices: Employ PV arrays designed as “eyebrows” or awnings over areas with view glass to provide appropriate passive solar shading. When sunshades are part of an integrated design approach, it often allows for smaller chiller capacity and reduced or eliminated perimeter cooling distribution.

6. Design for the local climate and environment: Designers should consider the impact of climate and environmental conditions on the PV array’s output. Factors such as cold, clear days increasing power production, surfaces reflecting light onto the array (e.g., snow), designing for potential snow and wind-loading conditions, shedding snow loads quickly with properly angled arrays, and the need for washing arrays in dry, dusty environments or those with heavy industrial or traffic pollution (e.g., auto, airline) to limit efficiency losses.

7. Address site planning and orientation issues: During the early design phase, ensure that the solar array receives maximum exposure to the sun without being shaded by nearby buildings or trees. It is crucial for the system to remain unshaded during the peak solar collection period, which consists of three hours on either side of solar noon. Shading has a significantly greater impact on the electrical harvest of a PV array than the shadow’s footprint.

8. Consider array orientation: The orientation of the array can significantly affect the annual energy output, with tilted arrays generating 50%–70% more electricity than vertical facades.

9. Reduce building envelope and other on-site loads: Minimize the BIPV system loads by implementing daylighting, utilizing energy-efficient motors, and adopting other peak reduction techniques whenever possible.

10. Engage professionals: BIPV is a relatively new field, so it’s essential to ensure that the design, installation, and maintenance professionals involved in the project are properly trained, licensed, certified, and experienced in working with PV systems.

11. Minimize the demands on the BIPV system by reducing loads originating from the building envelope and on-site sources. Implement strategies such as daylighting, utilization of energy-efficient motors, and other methods to decrease peak loads whenever feasible.

12. Expertise is crucial: Given the relatively recent emergence of BIPV, it is essential to guarantee that the design, installation, and maintenance professionals engaged in the project possess proper training, licenses, certifications, and experience in working with PV systems.


BIPV systems can be incorporated into a building either during its initial construction or as part of a retrofit project when one of the building envelope components requires replacement. The built environment offers numerous possibilities for integrating BIPV. Broadly speaking, there are three primary application areas for BIPV:

• Roofs (e.g., shingles, tiles, skylights)
• Façades (e.g., cladding, curtain walls, windows)
• Externally integrated systems (e.g., balcony railings, shading systems)