Controlling carbon emissions is a must to achieve the objective of limiting the global temperature rise within 1.5°C above the pre-industrial levels. The use of coal as fuel for energy production has to be replaced completely by non-greenhouse gas-emitting sources by 2050.
Coal accounts for roughly half of the energy-related emissions worldwide. A 500-MW thermal plant emits 3.7 million tonnes of carbon dioxide annually — equivalent to the axing of 161 million trees.
Pan-India, the share of installed capacity from non-fossil sources (solar, wind, biomass etc.) is expected to rise to 60 per cent (from 14 per cent) in the next 10 years. Punjab meets nearly two-thirds of its electricity requirement from coal-based sources and the rest from green sources such as hydel, solar and biomass. The state needs to increase the share of green energy sources, whose capacity is expected to be 4,771 MW (solar) and 277 MW (biomass). The solution to stubble-burning lies in optimum utilisation of stubble and other agricultural (and animal) waste from activities such as dairy farming for generating electricity and other byproducts.
Punjab produces about 25,842 kilo tonnes of surplus biomass from agriculture. Biomass does not release additional carbon dioxide into the atmosphere when used as fuel. One kg of rice straw with moisture content of 10 per cent generates 14 million joules of energy, which rises exponentially to 3,400 million joules when 100 per cent dry. This energy can be converted into electricity by biomass plants, whose installation costs around Rs 6 crore per MW. The Centre provides incentives for biomass generation, including tax exemption for 10 years, besides concessions on the cost of machinery and equipment. The cost of electricity generated is nearly Rs 6 per unit. However, instead of building bigger biomass plants, smaller ones need to be set up at the district level for facilitating easier transportation of rice straw to these plants.
Punjab experiences 250 to 300 sunny days annually, thus receiving radiation of 1,600 to 2,200 kwh/sq metre, which is ideal for generation of electricity. The state can set up solar plants of 1 to 10 MW capacity on canals and avail subsidy from the Union Ministry of New and Renewable Energy at the rate of 30 per cent of the project cost. The introduction of net metering has encouraged consumers to install rooftop solar panels. However, the target of 4,771-MW energy generation from solar sources is still far-fetched.
The Bhakra Beas Management Board (BBMB), primarily a hydroelectric generation company, is foraying into solar generation. Punjab State Power Corporation Limited (PSPCL) can follow the BBMB example by setting up its own solar plant (instead of private) of 175 MW capacity on 700 acres ash dyke area of the Bathinda thermal plant. The electricity generated would cost around Rs 2.5 per unit, besides the redistribution of spare manpower due to the closure of the coal-based plant.
Punjab’s hydel generation potential can be fully harnessed by setting up micro and mini projects on canals and rivulets. Three micro hydel power plants of total capacity of nearly 40 MW can be set on the Gulpur rivulet, presently used for the disposal of surplus water of the Upper Bari Doab Canal (UBDC) in lean periods.
Energy saved is more important than energy produced. Energy-saving measures can contribute towards reducing emissions, including the use of devices such as LEDs, efficient motors and pump sets. Curbing power theft, besides protecting the power utility’s revenue, also discourages wasteful use of energy.
Punjab needs a holistic and futuristic approach to meet its energy needs. Opportunities are available for exploiting renewable sources to tackle stubble-burning, make surroundings cleaner, and generate employment in rural and semi-rural areas.
The authors are power sector experts
Sunny side up
- A solar plant requires 3.5 to 4 acres per MW. The installation cost is Rs 5.5 crore per MW. Solar energy costs less than Rs 3 per unit.
Power generation from biomass (megawatts)
- 1,221 Maharashtra
- 872 Karnataka
- 842 Uttar Pradesh
- 627 Tamil Nadu
- 390 Andhra Pradesh
- 62.5 Punjab