Energy and climate protection

We make the strongest impact on environmental sustainability by increasing energy efficiency and protecting the climate. Solar power generation replaces other sources in the energy mix, thus contributing to reducing greenhouse gas emissions and preserving fossil resources.

Energy is needed throughout the entire production process of our products starting with the extraction of raw materials. However, the amount of energy used in production is far exceeded by the amount of electricity produced by the solar power system. In line with this, far more greenhouse gas emissions are reduced throughout the life cycle of the solar power system than are emitted throughout the entire production process. As a result, solar energy is a zero-emission source. Similar to the payback period of an investment, we use the terms energy payback time and CO2eq payback time to express how quickly the energy consumption and greenhouse gas emissions (measured in CO2eq) are compensated for.

Payback periods

For environmental reasons and to reduce costs, our goal is to lower energy consumption per production unit watt peak (Wp) along the entire value chain. This also allows us to reduce the greenhouse gas emissions associated with energy use. To achieve this, SolarWorld has been conducting life cycle analyses for several years. The result: While it takes a good year to compensate for energy consumption for the entire production process for a system in Bonn, it only takes eight months in San Francisco. In comparison: In 2008, energy payback was still 3.5 years in Germany (see Jungbluth et al.: Life Cycle Assessment of Photovoltaics: Update of ecoinvent data v2.0, Working Paper, ESU-services Ltd. (2008)). CO2eq emissions are compensated for the quickest for a system in the U.S. after a good year while it takes almost 10 years in France due to the high percentage of nuclear power.

Our Life Cycle Analysis was used as a basis to calculate the following energy and CO2eq payback times per region for polycrystalline modules (Freiberg production plant) installed in a roof with a southerly orientation and an optimum inclination at an average module lifespan of 30 years.*

Energy and Co2eq amortization times

* Assumption based on “Methodology Guidelines on Life Cycle Assessment of Photovoltaic Electricity”, IEA PVPS Task 12, Subtask 20, LCA, Report IEA-PVPS T12 – 01:2009, October 2009
** Calculation using country-specific energy mix data (Ecoinvent database)
*** Calculated using current calculation tools of the GHG Protocol.

Emission intensity

Since the Carbon Disclosure Project Germany was founded in 2005, we have been involved in capturing greenhouse gas emissions. In 2011, we successfully positioned ourselves as the industry leader for renewable energies. In 2011, our groupwide greenhouse gas emissions remained almost constant at 189 (2010: 179) thousand tCO2eq. We calculate the emission intensity of our products for the first time including the total emissions along the entire production chain. In 2011, we calculated a total of 0.8 kg CO2eq/Wp (2009: 1 kg CO2eq/Wp). This represents an improvement of 19 percent in just two years.

Positive CO_2eq balance