Renewable energy sources have lately taken center stage and it’s not without reason that they are considered the key feature of the fight against climate change. Although renewable energy sources could actually be considered the best option we have had so far, we still don’t know much about them, and we do not always take into account their limits.
We all know that solar energy is one of the most important and most widespread energy sources, particularly throughout our country, where the climate is suited for large-scale production of renewable energy. Solar photovoltaic panels are easy to assemble, at an affordable price and often the government provides subsidies to encourage the purchase of photovoltaics. Once solar panels have been installed, they only need a power plant, solar energy and their maintenance requires relatively little effort. Therefore, the use of solar panels is advantageous not only for homes and small communities, but also for small and medium-sized enterprises. The production of solar panels underwent significant changes over time, not only in terms of the use of raw materials necessary to produce them, but also in the lifespan of the product: if normally, a solar panel - installed in moderate weather conditions- has a lifespan of 25-30 years, the latest solar panels on the market have an expected lifespan of 50 or so years. That doesn’t mean that after this period they will stop working, but rather their output will decrease to 80% - 90% of the energy produced initially and then go down.
The primary components of a solar panel are silicon, metal, glass, but also precious metals and minerals such as silver, copper, and lithium. These materials are not unlimited, and they must be mined; the manufacturing process is not environmentally sustainable, and this represents the major contributor to carbon footprint related to the production of solar panels. Research shows that solar releases around 50 g of CO2 per kWh of electricity produced, including the manufacturing process (the mining of the materials, the assembly process etc.). The footprint of solar is significantly lower than the coal (more than 300 g) or gas (about 200 g), but still higher than the carbon footprint of wind and nuclear power. However, the industry of solar panels is constantly evolving towards sustainability.
The major issue concerning solar panels is their disposal. Some of the materials solar panels are composed of, like glass, plastic, and aluminum, can be easily reusable and recyclable, and this, on a side, means that part of the recycling of solar panels is sustainable; yet, on the other side, the cost of the disposal exceeds the profit generated by the sale of recycled materials, so it does not represent a strong incentive for a sustainable waste management. For this reason, many States strive to make it compulsory for the recycling industry to dispose of decommissioned solar panels properly. To this end, the European Community Directive of 2012, on waste electrical and electronic equipment, aims to collect, recycle and reuse electronic waste, which contains metals such as lithium.
A study conducted by IRENA and IEA-PVPS estimates that, by 2050, there will be up to 78 million tons of waste materials from solar panels. Due to the design of the solar panels, the disposal of their most hazardous materials is not that simple; moreover, if the modules are dumped in landfills, the toxic metals they contain can leach out into the environment. Despite all this, disposing of solar panels in landfills has been the most convenient choice so far. There are recycling companies, researchers, and solar panel manufacturers that are combining efforts to find efficient solutions to the waste disposal problem, while governments are trying to come up with appropriate legislation. The responsibility for waste management usually lies with the producer, although more support is being required from the States, both in terms of recycling incentives and in the investment in research for improving solar panels, making them more easily recyclable, more durable, and easier to fix in case of damage.
Translated by Iuliana Cindrea