Renewable energy from abandoned coal mines

The Ministry of Coal embarking on a plan to develop pump storage projects (PSPs) in abandoned coal mines is good news. Coal India Limited (CIL) has 20 abandoned coal mines for the evaluation and feasibility of PSPs, also known as water batteries. The findings of the evaluation will be crucial in drawing up an elaborate plan for optimal use of over 200 abandoned coal mines for generating alternative sources of energy. India has stepped up efforts to increase domestic coal production to end import dependence by 2025–26. This implies that the number of abandoned coal mines is going to increase in the coming decades, and more PSPs could be developed to increase alternative sources of energy. The PSPs use gravity flow to generate electricity by releasing water from a reservoir to rotate turbines to generate electricity when energy demand increases on the grid. Water is pumped into the storage during the lean period to be released depending on demand. The ministry plans to utilize solar energy for the generation of electricity during the day and use PSPs in abandoned coal mines during the night to feed clean energy into the grid. Official data shows that the overall coal production in October increased to 78.65 million metric tonnes (MT), surpassing the figures of 66.32 MT of the corresponding month last year and registering an increase of 18.59%. The production of Coal India Limited has increased to 61.07 MT in October this year as compared to 52.94 MT in October 2022, registering an increase of 15.36%. The cumulative coal production (up to October 2023) recorded an increase to 507.02 MT as compared to 448.49 MT during the same period in the last financial year, with an overall growth of 13.05%. The Ministry has launched the eighth round of the commercial coal mine auction process, and a total of 39 coal mines are going to be auctioned. The Ministry of Coal claims through an official release that since the first auction of commercial mining in 2020, a total of 91 coal mines have been successfully auctioned during a short period of three years in seven tranches under commercial coal mining. Out of these 91 coal mines, nine have received all the permissions, and five have started production. Production during FY23 from commercial mines was 7.2 million metric tonnes (MT), states the release issued by the Press Information Bureau. The government also plans to scale up coal production from underground mines to 100 MT by 2030. All these efforts and initiatives point towards coal production significantly increasing over the next couple of years. The successful development of PSPs in abandoned coal mines will be seen as a balancing act to offset the adverse impact of boosting coal mining on the environment. Increasing production of clean energy to meet domestic demand is also critical to India staying on course to meet its climate goal of phasing down coal towards meeting net zero goals. India’s target is to increase renewable energy in the energy mix to 50% by 2030. Currently, fossil fuels account for 56.3% of the energy mix, while coal dominates with a 48.7% share. Growing demand for electricity, driven by growth in the economy, has pushed up demand for coal. If alternative and renewable energy production does not increase proportionately, increased coal production may derail India’s climate targets. The Ministry of Power estimates that the country would require 26.7 Giga Watts (GW) of energy from PSPs and 47.2 GW of Battery Energy Storage Systems (BESS) to meet the demand for the integration of renewable energy into the energy mix until 2032. In this backdrop, the efforts by the Ministry of Coal to use abandoned coal mines for developing PSPs are expected to attract the attention of stakeholders in renewable energy. Although the running cost of PSPs is lower compared to BESS, the high upfront cost and high energy loss lead to a higher tariff, which makes it difficult for power developers to find power purchases and offer competitive prices. Feasibility studies into proposed PSPs in abandoned coal mines will have to factor in these realities and indicate how this problem would be addressed for the clarity of stakeholders and potential investors. In its guidelines for PSPs, the Power Ministry claims that apart from being non-polluting and environment-friendly, PSPs have a long service life of more than 40–50 years, which is much more than any other energy storage technology presently available and therefore results in a low cost of delivered energy over the life span of the projects. While these are strong arguments in support of climate goals, for power developers, commercial viability and competitiveness will influence their investment decisions. Afforestation on vacant land in abandoned coal mines needs to be prioritized for eco-restoration and reclaiming de-coaled sites for eco-tourism development for the benefit of local communities. At the individual level, reducing electricity consumption can significantly reduce coal production to check ecological destruction.