One of the questions about solar PV (photovoltaics) that I get asked is “what will be the negative environmental impact of solar PV modules (a.k.a. solar panels) when they’re not being used for power generation anymore?” “How about recycling?”
This is an important question because:
- some of the materials in the solar modules (e.g. lead and cadmium) could reach out and could harm the environment if they were buried as landfill waste. This is also true for other electronics, which is why there are free services for the public to drop off electronics for recycling (e.g. TVs, cell phones, microwaves, batteries).
- some of the materials in solar PV modules are rare and will become harder and harder to find and mine (e.g. silver, gallium, indium, germanium).
The reason that the answer to this question isn’t yet publically well-known, or finding space in the news, is that solar PV installations are relatively young and the number of solar PV modules at the end of their life, ready for recycling, is relatively low. In 2007 there were less than 10GW (DC) of solar PV modules installed globally. That total has grown exponentially to over 300GW as of 2016. Based on 300W per solar module, that is 1 billion solar modules. Despite this high number of solar modules in service, we have yet to see the associated exponential climb in solar modules ready for recycling because solar modules have a life expectancy of 25-30 years, with some older installations still in service, producing power after more than 40 years.
There are multiple PV recycling plants or businesses already operating with successful recycling of up to 90%-98% of the PV materials. The portion of recyclable materials that can be reclaimed, and the economics of recycling them, vary depending on the different chemistry of the solar module materials.
Associations across the globe help to facilitate and grow the availability of solar PV recycling plants. These associations work with solar PV manufacturers, solar PV recyclers, and with governments to set up regulations to help ensure that solar PV modules are disposed of in an environmentally conscientious manner. For example, based in Europe, there is the PV CYCLE association. In 2012, Europe explicitly added solar PV to a list of electronic equipment that requires dedicated treatment at the end of their life, by law (WEEE directive – Waste of Electric and Electronic Equipment).
For more information about solar PV recycling, check out Earth911, GreenMatch, ScienceDirect, Wikipedia, and PV CYCLE.