What is Building-Integrated Photovoltaics (BIPV)?

24/11/2015

Our country India is a developing economy whose GDP is growing at an average rate of 7% per annum. Also, we are one the largest energy consumers in the world and the demand are increasing every year. If we actually want to grow in real sense then we need to change our energy dynamics by gradually shifting from imported fossil fuels to self reliant renewable energy. And one such option & possibility is Building Integrated Photo-voltaics (BIPV).

Meaning of BIPV

BIPV are the building materials that generate electricity. These have same structural & physical characteristics as the normal building materials. It is the integration of solar energy system with the architectural building design in order to offer multi-functional properties of building materials and the electricity generation.

In India, the buildings are seldom energy efficient, although the trend is rising to make them energy effective and efficient but still there is long way to go.
Through BIPV, the vertical, horizontal and slanting areas of the building can be used to generate electricity from solar energy. The BIPV technology offers opportunity to convert windows & facades into solar panels and which can be used to generate electricity from sun light.
It is true that BIPV panels costs more than the normal window panels but in few years the break even is achieved as these panels produce electricity for the building.

The different types of BIPV

Flat Roofing: The thin film solar cells are integrated into flexible polymer roof. The flat roofing attracts the substantial amount of solar energy. Moreover, they require little adjustments in terms of placement and the orientation of the solar panels.
Facades: These can be mounted on the facade of the existing building in order to give it a new look. These require detailing and expertise so as to match with framing of the building.
Glazing: These are semi transparent modules which can be used as windows and skylights.

Technologies used in BIPV

It is found that it is better to design a new building with BIPV in mind against integrating BIPV in the existing buildings. The new buildings offer opportunity for suitable site and orientation which is not possible in the existing buildings. And because of this reason, the concept of retrofitting panels on the existing building is a costly affair with less energy efficiency. The thin film technologies are better suited for the BIPV applications as these technologies do not require optimal positioning to the sun and have better look and design.

Designing of new building with BIPV vs. BIPV retrofitting in the existing buildings:

Crystalline cells: These are made by slicing wafers and ingots
Thin film cells: The thin layer of PV material is deposited on the surface of materials like glass, plastic or steel

Benefits

It reduces the long term overall cost of the building when considering the energy consumption and the cost of the building material
The onsite production of electricity increases the efficiency and reduces the transmission loss.
It is suitable in densely populated areas like metropolitan cities
It looks aesthetically pleasant when compared with traditional solar PV system installed on the roof top
BIPV technology helps in reducing the CO2 emissions in the environment
Less reliance on grid connected power and can meet the demand in peak hours

Negatives

Smaller market penetration
Not price competitive
Infrastructure expertise is required

Conclusion

India has the vast potential to tap the solar energy in the form of BIPV. Although, this sophisticated technology is at nascent stage in India but by wider acceptance and implementation of it by the architects, developers & builders will help in creating awareness in consumers. Although, the high set up cost and the complex design constraints are the major blocks in its progress, therefore the right integration and the feasible economic parameters are required for the successful BIPV project. India is an energy deficit country and wide spread implementation of BIPV projects will help in making itself reliant in the upcoming years.