How Photovoltaic Diaphragms Work

EVA Resistant Lamibran® Diaphragm | Smartech InternationalThe photovoltaic industry relies on durable diaphragms to lower their costs when manufacturing solar panels. The use of solar panels on the roofs of commercial buildings and on residential structures has increased exponentially over the last several years. In 2014, there were 195,000 new photovoltaic installations in homes and businesses. New solar projects were installed every 2.5 minutes in the United States.

This trend is likely to continue as companies, governments and homeowners aim to conserve energy, contribute to environmental sustainability, and save money. Solar panels reduce the reliance on fossil fuels that emit greenhouse gasses into the atmosphere.

The challenge for the solar industry lies in selecting diaphragms that will not deteriorate. Understanding how photovoltaic diaphragms work will help both thin-film and crystalline solar panel manufacturers make informed decisions about the options available to them.  

Components of Photovoltaic Solar Panels

Photovoltaic panels are made of several layers including glass and aluminum that surround the actual solar cell. A layer of ethylene vinyl acetate (EVA) is used as an encapsulant to protect the highly sensitive solar cell. This is to sustain the cell’s power generating abilities through long term energy transfer, moisture accumulation and the impact of ultraviolet (UV) rays.

However, EVA has some side effects. Outgassing from the EVA as it becomes thermoplastic can degrade silicone diaphragms and cause them to become brittle, and then fail.

What Can Be Done to Prevent EVA Deterioration in Photovoltaic Diaphragms?

Steinbach developed the Lamibran diaphragm for the specific needs of the solar industry. Lamibran photovoltaic diaphragms are designed to resist the deterioration that results from EVA outgassing.

Lamibran diaphragms are constructed of two layers of material. One layer is made from Steinbach’s durometer 55 silicone. The second layer is resistant to the adverse effects of EVA which make standard silicone diaphragms deteriorate.

Another way to extend the life of the diaphragm is to protect the diaphragm with a layer of polytetrafluoroethylene (PTFE) placed between the module and the diaphragm. PTFE is a water-resistant, anti-corrosive polymer. PTFE is also highly heat resistant. Adding a sheet of PTFE within the module laminator can increase the life the diaphragm as well as provide other production benefits.

Smartech offers a complete line of PTFE sheets that can be customized to the size and thickness specifications required for the photovoltaic industry. Smartech also carries anti-static PTFE sheets static accumulation is a production issue.

Smartech also provides efficient logistics for stocking and shipping PTFE sheets and photovoltaic diaphragms. This ensures quick turnaround of orders that align with the lead times required by manufacturers.