The current focus on CO2 reduction is spurring governments, industry and consumers to seek viable alternatives to burning fossil fuels. As a result, demand for clean, renewable energy sources is growing. This is great news for the environment, and now there’s more focus than ever before on making production processes even more energy efficient. As a supplier of high-performance valves for the production of solar cell materials, Danfoss has found a way to improve the solar cell manufacturing process.

Solar power production gets greener
Solar power energy is one of the fastest growing energy technologies in the world. As demand for solar energy grows, so too does the demand for solar or photovoltaic cells, which convert solar energy into electricity. Photovoltaic cells are great news for the environment – they harness a renewable energy source – and they don’t emit any CO2. But a lot of energy goes into their production, and Danfoss is behind efforts to make the photovoltaic cell manufacturing process more energy efficient.

Photovoltaic cells are made of silicon wafers. The wafers are made from quartz sand, which goes through a high-temperature casting process to transform the sand into silicon blocks. To clean and liquefy the sand, it is heated to over 1200°C in a hermetically sealed chamber. Danfoss high vacuum valves help control the atmosphere and heat in the chamber, drawing out air and gases during the venting process. During the meltdown process, the vacuum valves work to get the chamber quickly up to the desired temperature, and raising the pressure to four to five bar, by forcing a special gas into the chamber. And lastly, the chamber is cooled down and the silicon blocks removed for cutting into silicon wafers.

To cope with this extreme manufacturing process and make the process more energy efficient, Danfoss has developed a new generation of pneumatically operated vacuum valves resistant to high temperatures. With the new generation valves, higher temperatures and gas pressures can be reached in the chamber, reducing production time and energy consumption. More silicon blocks can be produced using less energy, which means a reduction in CO2 emissions. And that means more silicon wafers to meet the growing demand for photovoltaic cells.

Like vacuum valves, Danfoss solutions are parts of vital processes. And if they need improving, we listen and respond.

Courtesy of Danfoss