Intersection of Green Buildings and Photovoltaic (PV) solar power
Government tax incentives and stimulus grants, such as those from ARRA, international and national mandates, such as the Kyoto Accords, and state and local regulations, such CALGREEN and Net Zero Energy Buildings in California, have driven demand for energy efficient and environment-friendly Green Buildings.
The European Union through the The Climate and Energy Package and Renewable Energy Directive, adopted by the European Parliament in 2008 as well as efforts by individual governments have pushed for greater adoption of renewables, including BIPV, through a series of subsidies, interest-free loans, feed-in tariffs, and tax incentives. For example, France has offered the highest incentive for BIPV since 2006 followed by Germany, Italy, and Spain. As a result, Europe accounted for 82% of world demand for PV in 2008.
As China’s economic growth continues, it is attempting to reduce carbon dioxide emissions and environmental damage due to its extensive use of coal for electricity generation. China is not only one of the largest producers of solar cells, but also presents a very large market for BIPV. Under the 2006 Renewable Energy Law, feed-in tariffs and subsidies, such as the Golden Sun Program that can cover 50 to 70 percent of the cost of solar systems, were put in place to achieve the goal of 1,800 MW (15 percent of the total energy consumption) installed capacity of solar PV of by 2020.
The Goal: Distributed Energy Generation, Net Zero Energy Buildings
This demand coupled with the declining cost of (PV) creates a perfect climate for distributed energy generation at the built site. Combined with energy efficient building material will enable the realization of self-powered, Net Zero Energy Buildings. Only BIPV, serving as energy-efficient building envelope material—windows, skylights, facades, and power generator, can provide savings in materials and electricity costs, reduce use of fossil fuels and carbon dioxide emissions, and add aesthetics to the building, creating economic value and driving mainstream adoption.
In fact, the United States Department of Energy estimates that BIPV technology has the potential to generate up to half of the electricity needed in the country at the place where it is needed most, the point of consumption. BIPV is, in fact, an estimated $1.6 B (rigid modules and glass) distributed generation market and one of fastest growing segments of the PV industry with an expected 20 percent CAGR.
BIPV has several advantages:
Economic
- Replaces materials that would be otherwise used in the building
- Integrates into design and construction processes
- Leverages existing building suppliers and construction practices
- Reduces installation and integration cost
- Reduces energy consumption
- Eliminates energy transportation costs and infrastructure
Environment
- Reduces CO2 emissions significantly; energy generated within building
- Makes efficient use of landscape
- Reduces environmental impact of energy transportation
Despite these advantages, BIPV faces barriers to widespread adoption, including:
- BIPV is usually one of several isolated and uncoordinated technologies dealing with heating/cooling, energy generation, and natural lighting
- Rooftop PV arrays can be a liability for the building owner; insurance can be cancelled
- PV arrays are often not a possibility due to small roof size
- Aesthetics—PV arrays mar the building profile and scenic views
The Pythagoras Solar Solution
Pythagoras Solar overcomes these barriers by taking a unique integrated approach to energy efficiency and generation, natural lighting, and aesthetics. Pythagoras’ Photovoltaic Glass Unit (PVGU) uses patent-pending optical technology, high-efficiency silicon, and advanced materials to provide the industry’s first highest-transparency and highest-density PV power generation in a standard double-pane window form factor, known in the industry as an insulating glass unit, or IGU. The PVGU leverages the modularity and ease of installation of the IGU while controlling direct solar radiation and providing greater transparency to further increase the energy efficiency gains through reduced heating/cooling and lighting costs.
The PVGU’s ”Triple Value” extends the advantages of BIPV through:
Energy efficiency
- Extremely low solar heat gain coefficient
- Low U-values
- Daylighting
Energy generation
- 4X power density of existing BIPV technologies
Aesthetics
- High transparency
- Choice of colors
- Modern look
- Adaptable design
- Available in skylight, curtain wall, and colored tiles
The PVGU will make buildings more efficient, greener, and more profitable. Unlike other BIPV applications, the PVGU’s “Triple Value” with its architectural adaptability and economics ensures that it can be quickly and easily adopted by the construction industry, including architects, engineers, contractors, and building owners. Its adoption will be accelerated further by government subsidies focused on energy security and climate change. This will increase the amount of distributed renewable energy generation, add considerable value to buildings, and push ubiquitous solar and Net Zero Energy Buildings toward a wider reality.