Arizona-headquartered thin-film solar producer First Solar has published this week its inaugural Corporate Sustainability Report, which outlines the steps the company is taking to reduce its carbon footprint and lower the impact of its PV plant projects across their life cycle.
The report sheds light in First Solars life cycle management process, which is a key link in the companys production chain. Manufacturing First Solars thin film panels is a less energy-intensive process than typical silicon crystalline solar modules, but responsible management and disposal of the mining byproducts is imperative, the company states.
The semiconductor material in First Solar panels is comprised of Cadmium (Cd), which is a byproduct of zinc refining, and tellurium (Te), which comes from copper. First Solar encapsulates these materials, CdTe, into its modules, which have a 25-year warranty. At the end of the modules life cycle, the company employs a global recycling service that extracts the CdTe to be used again in production of new modules.
The modules themselves, the company outlines in the report, are up to 9% more efficient that C-Si modules when temperature coefficient, spectral response and shading performance are considered. These advantages vary greatly under certain climatic conditions, and the company states that its thin film delivers more efficacy in hot and humid climates, often in regions where environmental concerns amount to tackling life-threatening natural disasters.
The report also explores a typical thin film modules carbon footprint, which the company claims is the smallest of all technologies at just 12 gCO2/kWh compared to multi-Si PV at 24 gCO2/kWh. Production also requires less water, at just 400 liters per MWh, compared to 1,900 liters/MWh for Si-PV and up to 120,000/MWh for nuclear.
Recycling and efficient production key to lower emissions
The report makes a big play on First Solars efforts to deliver a virtuous loop of production. The company operates recycling facilities in the U.S., Germany and Malaysia, recovering 90% of the glass and more than 90% of the semiconductor used in the modules. A third-party company handles the separation and refining of the Cd and Te, which is separated in the recycling plant from the glass in a batch reactor.
The process of sourcing of raw materials is also outlined in the report, revealing that First Solar expects a future oversupply of Cd as demand for the material decreases. According to the company, thin film module production is a steady outlet valve for the hazardous material, which would otherwise be stored or disposed of. For Te, the company maintains a "strategic reserve" of products to insulate the company from supply or price volatility.
In 2014, 12.5% of the Te used in First Solar production came from recycled sources. The company is eyeing an increase of that percentage in 2016.
In terms of manufacturing timescales, First Solar claims that it can transform a sheet of glass into a complete PV module flash-tested, boxed and ready for shipment in under 2.5 hours, and is targeting even shorter timeframes in order to bring down further its carbon footprint. In 2012, the firm targeted a 35% reduction in greenhouse gas (GHG) intensity by 2016, based on 2008 levels of output. First Solar says that it hit that target in 2014 with the addition of its cleaner Malaysia factory.
"We are proud of the steps we have taken to improve the environmental profile of our products and operations while contributing to communities where we live and work," said First Solar VP of global technical services Alex Heard. "By continuously driving down the cost of solar electricity and providing a solution that addresses energy security and water scarcity, we are delivering on our commitment to build a more sustainable energy future for everyone."