Technology - Building Integrated Photovoltaics

BIPV Technology

In one minute, the sun provides enough energy to supply the world's energy needs for one year.

In one day, it provides more energy than the world's population could consume in 27 years.

The sun's energy is free, and the supply is abundant. All we need to do is find a way to use it.

A Swiss scientist first figured out a way to harness the sun's energy in 1767, when he used a solar collector to heat water and cook food. So the idea of putting the energy of the sun to work has been around for a long time. We just need to find more ways to use it in our daily lives. One such way is called Building Integrated Photovoltaics or BIPV Technology.

Imagine you own a building—a home, school, business, warehouse, hotel, restaurant, store, or whatever you like. Imagine your building is producing some of the electricity it needs in a quiet and clean manner with no fuel costs or large equipment.

Imagine the electricity-generating device has a long lifetime and low maintenance costs with no moving parts, noise, emissions, or fuel lines. Now imagine that this device is actually the walls, roof, and windows of your building-the same structure that keeps out the rain, heat, snow, and cold. It's not Science Fiction! It's Building Integrated Photovoltaics, and it is a very real part of building construction today.

What are Photovoltaics?

Photovoltaics (PV) are solid-state, semi-conductor type devices that produce electricity when exposed to light. Broken down, the word photovoltaics actually means "electricity from light." Many hand-held calculators run off power from room light, which would be one example of this phenomenon. Larger power applications for this technology are also possible. The figure shows how photovoltaics works. Sunlight knocks electrons free in the photovoltaic material, which flow out of the device as electric current. The more intense the sunlight, the stronger the electric current.

Understanding Building Integrated Photovoltaics

With Building Integrated Photovoltaics (BIPV), photovoltaic material becomes an integral part of the building: the walls, roof, and vision glass. Sunlight falling on the photovoltaic components creates electricity. This electricity flows through power conversion equipment and into the building's electrical distribution system, feeding electricity to the building's electrical loads. In essence, the skin of the building produces electricity for the building, typically enough to power three to five classrooms. This activity occurs in conjunction with traditional electricity supplied by such companies as Wisconsin Public Service.

BIPV technology is widely used throughout Europe, but is just beginning to be applied here in the United States. Most U.S. architects, engineering firms, building owners, and builders know very little about Building Integrated Photovoltaics. The majority of BIPV products exist for commercial construction, and commercial buildings can accommodate the several thousand dollar cost required for installing even a small one-kilowatt BIPV system. The technical potential in commercial buildings is significant, and they suffer fewer problems from orientation and shading.