Why India’s canals could help fast-forward its solar energy plans

By Mukta Patil

Mehsana (Gujarat): As far as the eye can see, line after line of solar panels stretch out in the midday sun beating down on the village of Chandrasan here in this eastern Gujarat district, which squeezes in 80 more people per sq km than Indias already crowded average of 441.

But there is no land conflict involved with the Chandrasan installation because the solar panels unfurl over a 750 m length of irrigation canal.

The panels were installed in India's sunniest state in 2012 and now offer hope for a country three times as densely populated as China, at a time when India aims for almost a nine-fold increase in solar capacity between between 2017 and 2022 to fulfil global climate-change commitments and reduce its dependence on coal-fired power plants.

The canal-top idea was first tabled at a 2011 Vibrant Gujarat Summit by the then Chief Minister Narendra Modi, said Bela Jani, a spokesperson at state-owned Gujarat State Electricity Corporation Limited (GSECL). The aim was to utilise the area above the canals, saving the government the cost, time and inconvenience associated with land acquisition.

Gujarat alone has a canal network of 80,000 km. Using even 30 per cent of this network for canal-top solar projects, according to GSECL estimates, 18,000 MW of power could be produced in just Gujarat -- almost equal to the current coal-based installed capacity of Delhi, Rajasthan and Telangana -- and 90,000 acres of land, or twice the size of Kolkata, could be saved.

In other words, installing solar-panels over 30 per cent of Gujarat's canals could be used to meet nearly a fifth of India's solar power targets by 2022.

Currently, about 100 MW of solar installations atop and besides canals are either approved or under construction in eight Indian states. Government subsidies are limited to public-sector companies that own canals or canal banks, but, if successful, private-sector involvement is inevitable.

Solar power is important to India's future electricity needs

Coal generates over 75 per cent of India's electricity and is among the cheapest energy sources available, IndiaSpend reported in May 2015.

With over 300 million Indians without reliable energy, and industrial demand growing, the need for coal-fired electricity is estimated to increase three times by 2030, with consequent environmental impacts.

But in talking about what he calls the "seven horses of energy" -- coal, nuclear, hydro, gas, solar, wind and biogas -- Prime Minister Narendra Modi has declared that India's efforts should increasingly move towards the latter three.

The real potential in a sunny country to replace fossil fuels is solar: India has a renewable-energy potential of about 895 GW, of which 750 GW is solar, as IndiaSpend reported in February 2015.

By 2022, solar energy could achieve grid-parity in India, meaning it would cost the same as other sources of electricity -- although some reports suggest this might happen by 2018. That is the year, as another IndiaSpend report said, the renewable-energy sector, primarily solar, could generate 1 million jobs -- over the 400,000 that already exist, according to a 2016 status report by Renewable Energy Policy Network for the 21st Century, a global, multi-stakeholder network based out of Paris.

Solar power plants can be built faster than either coal, gas or nuclear power plants. Further, in the decade ending 2014, solar installed capacity went up from 2.6 GW to 139 GW, a jump of 50 times over the initial capacity in just 10 years, largely because of falling costs and improving solar-cell technology.

The critical issue around solar installations in India is space, as IndiaSpend reported in May 2015. That is where the nation's canals come in.

Canal-top solar power is most efficient, has longer life and saves water

The power output of ground-mounted solar panels decreases at a rate of 1 per cent every year for the first 10 years. However, panels mounted on Chandrasan's canal showed no degradation and power generated stayed stable over the past three years, according to research conducted by the Gujarat Energy Research and Management Institute (GERMI), a research institution promoted by the Gujarat State Petroleum Corporation Ltd, a central government undertaking.

"Not only do they perform more efficiently, but because we can assume that the generated electricity is utilised in nearby areas, the transmission losses of (normally) 4 per cent and distribution losses of 3 per cent are avoided," said Sagarkumar Agravat, head of GERMI's solar research and development.

Apart from this, since the panels are placed on top of water, they are cooled from below, which also increases their efficiency and enhances output by 2.5-5 per cent.

Essentially, this means the panels will last longer than 25 years, which is the average lifespan of a ground-mounted solar panel, while producing more power due to increased efficiency.

The study concluded that canal-top installations outperform both traditional ground- mounted solar installations and systems on canal banks.

Canal-top panels, by absorbing heat, help reduce water evaporation. A 1-MW canal-top plant can save the evaporation of up to 9 million litres of water per year, according to a GSECL estimate shared with IndiaSpend, saving enough to provide 2,500 households with 10 litres of water every day for a year. As more canals are covered, the savings increase.

The use of solar energy also stops the emission of close to 1.28 million metric tonnes per year of carbon dioxide (CO2), a major greenhouse gas, according to this report. This is roughly equivalent to the annual energy use of 110,000 American households saved from a 1 MW plant.

Why solar power is important to India's climate-change commitments

By 2030, global greenhouse-gas emissions are expected to reach 54-56 giga-tonnes of CO2 equivalent (GtCO2eq) -- far exceeding the level of 42 required to limit global warming to 2 degrees C by 2100, according to data from the Emissions Gap Report 2016, compiled by the United Nations Environment Programme every year.

The Paris Agreement, which aims to hold temperature rise to below 2?C by 2100 compared to pre-industrial levels, came into force on November 4, 2016, barely a month after India ratified the treaty on October 2, 2016.

The 2016 Emissions Gap Report also states that despite full implementation of all the Paris pledges submitted by countries under their Nationally Determined Contribution (NDC), global temperatures are still set to rise to levels ranging from 2.9?C to 3.4?C. This means that countries must now go beyond their intended contributions if they hope to arrest global warming.

As part of its Intended Nationally Determined Contribution, India has committed to source 40 per cent of its electricity from non-fossil fuel sources by 2030. By October 2016, renewable installations amounted to nearly 15 per cent of the installed energy capacity, according to the Central Electricity Authority.

(In arrangement with IndiaSpend.org, a data-driven, non-profit, public interest journalism platform, with whom Mukta Patil is an analyst. The views expressed are those of IndiaSpend. Feedback at respond@indiaspend.org)