Optimal Utilization of Coal Ash, Barren Land, and Application of Agrivoltaics for Sustainable Communities in the Phase-down Scenario of Coal in India

Globally, India has one of the lowest per capita available lands for agriculture. With the increase in population, the per capita available land for agriculture has reduced by 45% over the last 30 years. About 10% of land in India is barren, while 44% is cultivated and as much as 16,684,000 hectares (ha) of land is barren, and not viable for agriculture [1]. In addition, more than 26,305 ha of land are being used for holding coal ash generated from thermal power stations, which can be put to productive and sustainable use [2]. Coal ash is a by-product of fossil fuel coal-based thermal power generation, which can be utilized in agriculture by replacing/providing the much-required topsoil in barren land.

It may be noted that out of 430 billion kWh (gigawatt-hour, GWh) electricity generated in the first quarter of 2024 in India [3] and [4], 82% came through non-renewable thermal routes, of which 74% from coal only, producing 271 million tons of ash [5 and 4]. India’s 24% of coal, 85% of oil and 50% of natural gas are imported at a huge energy bill of $160 billion (USD) in the year 2023 [5]—coal import has increased to more than seven times in last two decades. For a developing economy with largest population of the world, India is talking the most crucial task of attaining overall sustainability with decarbonization of the economy, most challengingly the phasing down of coal.

This article proposes a novel approach to convert barren land for agrivoltaics i.e., the dual use of ground-mounted solar photovoltaic (SPV) projects and agriculture (Figures 1 and 2) at the underneath of the panels using ash as a base topsoil instead of soil. Preliminary results have shown successful growth of edible vegetables and flowers in an in-situ experiment. The proposed model can serve as a sustainable model for ash utilization, judicious land use, renewable energy generation, and support to local communities for employment generation and food production. Large-scale adoption of the proposed model is expected to propel India to attain the above-mentioned benefits along with the target of achieving net zero by 2070.

This article was originally published in the 国际能源管理杂志 (IJEM Vol. 6, Iss. 5, 2024) by Shiv Shyam and Dr. Binoy K. Choudhury. Read the full article 这里.