Waste-to-energy technologies contribute to a more resilient and secure energy infrastructure by utilising local waste resources. This reduces dependence on imported energy sources and enhances energy security for a region or country
Waste-to-energy technologies reduce greenhouse gas emissions through three mechanisms: generating electrical power or steam, eliminating methane emissions from landfills, and recovering ferrous and nonferrous metals from municipal solid waste. These technologies play a significant role in the pathway towards carbon neutrality by addressing two critical challenges: waste management and energy production.
The United Nations has set ambitious targets for global net CO2 emissions to decrease by 45 percent by 2030 and reach net zero by 2050. However, the current emissions are estimated to be around 52 Gt CO2 eq, leaving a significant gap in climate action.
This gap necessitates faster energy transitions, digitalization in materials, operational management, and infrastructure design, which could drive low-carbon development and create a win-win situation for stakeholders.
Rising incomes and industrialisation in India lead to increased waste generation, with increased consumption of consumer products resulting in increased municipal solid waste. Despite strict policies on waste segregation, residential, commercial, and institutional wastes mix with other wastes from industrial, municipal services, hospitals, construction, and demolition.
India's cultural diversity and diverse lifestyles contribute to the high organic content of its waste, with only 12.45 percent of urban waste being responsibly processed and the rest disposed of in open dumps.
Municipal Solid Waste (MSW) at dump sites contains a mix of organic and inorganic inert waste, with the organic part suitable for aerobic composting. However, this process is time-consuming and emits significant greenhouse gases. Composting also pollutes groundwater during decomposition, similar to open dumping.
Farmers are hesitant to use city compost due to concerns about heavy metals and unwanted content in the food chain. Anaerobic digestion, or bio-methanation, is an environmentally friendly alternative, but it is time-consuming and requires large-scale urban MSW handling.
Thermal processing of waste to generate electricity reduces waste volume by 80 percent. However, the first large-scale 300 tons per day incineration plant in Delhi struggled due to non-availability of waste with the required calorific value. The government has revamped the Municipal Solid Wastes Rules 2000 and notified the new Solid Waste Management Rules 2016, authorising source segregation, recycling, and power generation from 6,276 kJ/kg waste.
Traditional waste management practises, such as land-filling, can result in the release of methane, a potent greenhouse gas. By converting waste into energy through technologies like incineration or anaerobic digestion, methane emissions can be minimised, contributing to a reduction in overall greenhouse gas emissions. Waste-to-energy facilities produce electricity or heat from the combustion of waste materials.
This energy generation contributes to the diversification of the energy mix and reduces reliance on fossil fuels. In turn, this helps decrease carbon dioxide (CO2) emissions associated with conventional energy production.
WTE technologies often involve the recovery of valuable resources from waste, such as metals and certain chemicals. This aligns with the principles of a circular economy, where materials are reused, recycled, or converted into energy instead of being disposed of in landfills.
Instead of sending waste to landfills, which can emit harmful gases and take up valuable land, waste-to-energy processes divert a significant portion of the waste stream. This not only reduces the environmental impact of landfills but also contributes to the efficient utilisation of waste as a resource.
By producing energy from waste, WTE technologies contribute to offsetting the need for energy derived from fossil fuels. This substitution helps reduce carbon emissions that would have occurred if the energy were generated through conventional means.
Waste-to-energy technologies contribute to a more resilient and secure energy infrastructure by utilising local waste resources. This reduces dependence on imported energy sources and enhances energy security for a region or country.
It is important to note that India needs to revisit advanced thermal controlled combustion technologies for waste-to-energy generation, similar to countries like China, Germany, USA, and Japan.
These technologies minimise environmental emissions and ensure economic and technical viability. The structural suitability of MSW should be reviewed to meet the requirements for economically viable treatment in any downstream technological process.
Environmental impact of waste-to-energy technologies can vary depending on factors such as the specific technology used, waste composition, and operational practises. Therefore, the successful integration of waste-to-energy into a carbon neutrality strategy requires careful planning, monitoring, and adherence to environmental standards.
(Prashant Singh, Co-Founder and CEO of Blue Planet Environmental Solutions)