“There is no such thing as away. When you throw something away, it must go somewhere.”— Annie Leonard
Previously the PV cell energy was used in space programmes only. But, to fulfill the ever rising demand for energy, the PV cell energy can be a solution to the problem. The use of PV (photovoltaic) cells is increasing day by day as solar energy is the third most used renewable energy after the hydro energy and wind energy and it is also a good source of electricity generation in replacement of coal generated electricity as the carbon emission is negligible by the silicon based PV cells, and fossil fuel based electricity generation produce 400 g and 1000 g CO2 eq/kWh. In 2017 the capacity of globally installed PV was 400 GW and it was predicted to increase to 4500 GW by 2050. The year 2017 was considered as a time of highest growth in PV energy generation as maximum PV cells were installed in that year. The solar power using PV cell had added more energy as compare to fossil generated energy and nuclear energy. The growth in solar energy is 99.1 GW (installed in 2017), only followed by wind energy generation of 52 GW in that year; remaining major energy generation methods use nuclear, coal, hydro and gas. It is evident that the world is now moving towards renewable energy which is essential for a better environmental condition. But with this the issue of PV waste is also a major concern for future.
World Scenario of PV Energy & Waste
Many countries around the world had stated extensive installation of PV cells for energy generation, In 2018 Saudi Arab had proposed a tender for the generation of 300 MW plant for the solar energy production at the lost cost of 0.0234 USD/kWh, China alone has installed 50% of the solar generation PV cells in 2017. It is predicted that by the end of 2022, global solar energy generation capacity should reach 1270.5 GW. As the technology is improving it will also reduce the cost of solar energy generation. Recently European Union had included PV waste in their WEEE directives to reduce regulate the waste of PV panels and it prohibit the export of PV waste in Europe. These directives were helpful in reducing the environmental impact of PV waste as well as promoting its recycling. The popular promotion of solar energy by nations dates back to 2007 as in 2007, Germany was the first nation to commercialise the solar energy and connected it to the national grid and decide the tariff for its usage. At that time the total installed capacity was 9.2 GW and by the end of 2017 the total global installed capacity of PV panels is around 400 GW. A major increase has been seen in the solar power generation using PV cells. The Asia pacific region had contributed 55% of the total global PV installed in 2017 and was followed by USA and Germany. China was the world’s largest nation for solar power generation during 2017. India constituted 5% of the total PV capacity installed in 2017 which showed that India was a major promoter of solar energy. It can be seen in the formation of International Solar Alliance in which India is a signatory with France which promotes the solar energy around the globe to reduce the dependency on fossil fuel.
However, the World scenario of waste is much more dangerous than we think. According to Surbhi Singhvi from ‘Bridge to India’: “Solar waste just finds a mention in one place – the tender documents (of solar projects) – wherein it is said that the solar power developers are responsible to dispose the waste in line with the electronic waste rules. But the e-waste rules make no mention of the solar panel waste. So, it is no one’s responsibility.” The world is constantly at war, the greed for power and money and due to these things important things comes in the background and PV waste management is one of them. The boom of PV cells started around 2016 in India and the promotion is at its peak now. But people are not aware of the future hazard which is related to PV waste. The general notion is that the waste is only generated when the life of PV cells ends, but the waste which is generated during manufacturing, transport, installation and in many other activities goes unchecked.
According to a study named “An overview of solar photovoltaic panels’ end-of-life material recycling”, till 2050 the world will be producing 78 million ton of PV waste. According to IRENA the global PV waste at the end of 2016 was 250000 tons .Different Nations in the world which are a major producer of solar panels do not have any solid framework for its safe disposal. Generally, the EOL age of the PV panel is 25 years which means that we will see a large chunk of solar waste during 2040-2050. Japan in 2016 generated 10,000 tons of PV waste and they estimated that this waste generation will increase up to 800000 tons till 2040 and they did not have any framework for its disposal. In a statement by Toshiba Environmental solution, it will take 19 years for Japan to reprocess all the waste it generated till 2020. In this it can be seen that the solar waste takes a lot of time to process and dispose but the nations are generating a large amount of waste on an annual basis. “Recycling makes sense when one considers the energy consumption in manufacturing. But if we recycle solar panels, we will not need as many materials,” points out Anil Kottantharayil, IIT, Bombay.
China is on the same path as Japan, it produces two times more panels than USA alone and still has no policy or framework to its disposal and reprocessing and the same goes for California which is also a major producer of solar PV panels. European Union have directives for it but it is not the responsibility of the Europe alone to dispose its PV waste. “Leaching of lead has a huge environmental impact—loss in biodiversity, decreased growth and reproductive rates in plants and animals, and several other health hazards—adverse impact on kidney function, nervous, immune, reproductive and cardiovascular systems. Cadmium is a carcinogen with high toxicity as well as high accumulation potential in humans.” says a Bridge to India (BIT) Report.
The PV waste can be disposed on the regular site and can be dumped after EOL but the chances of leaching down of harmful chemicals such as lead, cadmium etc. in the ground and then contaminating the water, which causes another hazard. It is true that the world is moving towards the renewable energy and it is also very suitable for regulating the CO2 emission but due to ta lack of framework and policies for PV disposal, it will be very difficult to sustain this activity in the near future. Nowadays nations like Japan, Europe and the USA are trying to recycle the PV waste and their main focus is on Si based PV cell. There are only three process known for the recycling of the PV waste i.e., physical, thermal and chemical. “We need research and development because the accumulation of waste will sneak up on us," claims Timothy Silverman (NREL). It is stated in the context of PV waste as there is a need for research for the sake of reducing the impact of PV waste on global waste scenario.
Though recycling of PV waste is done by various agencies and firms, it is very necessary for a sustainable use PV in the coming future. ‘First Solar’ is a solar panel manufacturing company which also provides solution for the recycling of PV waste. They have a recycling process which is composed of the shredding of PV modules firstly into large pieces and then into smaller one (less than 5mm). After that the slow leaching drums are used to remove semiconductor films, the glass is mixed with sulphuric acid and hydrogen peroxide to attain a proper solid liquid ratio; then the glass is separated. Vibrating screen is used to separate the glass from ethylene vinyl acetate pieces. Cleaning of glass is done and supplied to industry for recycling. Metal compounds are precipitated by sodium hydroxide and then are sent to industry for the manufacturing of semiconductor grade raw material to be used is PV modules. The recovery rate of glass is 90% and 95% for semiconductors attained from this process.
Indian Scenario of PV Energy
India is a tropical country and it receives 300 clear sun days around the year; 5000 trillion (kWh/year) solar radiation is received by India. If proper technology is used to harness this radiation, then India will be able to produce surplus energy above its national consumption. Indian power sector is divided into five regions i.e., Northern Region (NR), Eastern Region (ER), North Eastern Region (NER), Southern Region (SR) and Western Region (WR). In 2014, the total energy demand of India was 91433 Mu and as we only generated 87488 MU, we are at energy deficit. In 2015, as compared to 2014, the energy deficit was reduced. In 2015 Jammu Kashmir had the largest power deficit of 14% which was followed by Karnataka and Uttar Pradesh at 13%. As the population of the nation is increasing day by day, the set-up of new industry and development of new technology requiring energy, produce higher energy demand. According to data, the total power generation till October 2015 was 280328.5 MW and out of that 195604.44 MW was generated using thermal power plant. It clearly showed that a large amount of electricity was still produced from the fossil fuel which in turn resulted in environmental pollution .This gave a major scope to the renewable energy production method to be at the forefront of the energy generation. It is estimated that Indian has a solar potential of 750 GW. In 2010 JNNSM (Jawaharlal Nehru National Solar Mission) was launched with a vision of 100 GW Solar installations till 2022. It was planned to install 40 GW of PV cells on rooftop and 60 GW connected to the grid. A plan of 46 solar parks was sanctioned in 2018 for the installation of 26 GW. India had already achieved the 20.81 GW of target till March 2019 according to the Ministry of New and Renewable Energy. According to NITI Aayog, there is a possibility that India will reach the capacity of 479 GW solar energy generations by 2047. But, with the growth of PV cell installation the possibility of waste generation is also increasing. As a part of International Solar Alliance, it is important for India to move towards a fossil fuel free energy generation but to achieve that target India must manage and regulate its PV waste. The projection of Installed capacity of PV in India is 90% for the ground mounted plants, 10% for roof top installation and off grid system share is negligible around at 1%. Some achievements by India in the field of renewable energy till 2015 were, 42% increase in solar capacity during 2014-15, NTPC tender for the setup of 2170 MW solar project and many more. And these achievements are increasing day by day.
Indian Scenario of PV Waste
It is measured that 2 meter sq of PV panel uses 20gm of silver, so in context of India, if the recycling of PV panel is not well regulated, we will lose a lot of silver in the waste which will impact the economy of the PV industry. The PV industry is also prone to economic crises; India is a major importer of silver. In the year 2019, a quantity of 5598 ton of silver was imported. In context of India, three scenarios were made to estimate the amount of PV waste generated in different conditions. If we talk about the low scenario, India will generate 11 kilo ton of PV waste by 2030, 21 kilo ton in medium scenario and 34 kilo ton in high scenario. The amount of waste which is due to EOL (End of Life) of PV panel is not added in the above mentioned figures as the generation of PV waste EOL will be significant after 2040 only as the life of PV panels is 25 to 30 years.
The world and Indian Scenario show that there is a great future ahead for the PV solar energy production and the nations are advancing at a rapid rate in the field of renewable energy generation. But, beside the development in renewable energy generation, the hazards are also present. Nations are very much focused on the installation process of PV cells rather than thinking about the methods to manage the PV waste in future. We are falling back on recycling and reuse and if this scenario continues, it will cause greater waste hazard in future which will be hard to deal with. For achieving this, all the nation must come together for the formation of a framework or a binding policy for the entire signatory, and develop sustainable mechanism for the reuse and recycle of the PV waste and reduce the disposal as much as possible. India has a larger potential for the production of renewable energy in the form of solar power. Being a tropical country, India has an advantage of having more radiation from the sun; the utilization of this radiation by tropical countries can help in producing surplus energy (above consumption). In the near future, tropical countries will be the flag bearers of the solar revolution for the whole world. India must act fast.