Delhi’s T3 airport has a sculpture series depicting ten postures of the Surya Namaskar (salutation to the Sun), a yoga routine. It is a symbol that Indians recognise the vital importance of the Sun, without which life cannot exist on this planet, and worship it for this. Yet, we have not harnessed the full potential of the Sun for our everyday energy needs, which seem to be on the rise.
Our planet receives solar energy amounting to 3,500 times the energy that the entire human race is expected to consume in 2050. If only we knew how to harness this energy cost-effectively, we would not have polluted the earth’s environment as much as we have with our reliance on fossil-fuel-fired thermal power. The ministry of new and renewable energy (MNRE) has estimated that India alone has a solar energy potential of 7,48,990 MW, as against the current commissioned capacity of around 3,000 MW. The slow pace of tapping solar energy has been due to its high costs compared to thermal energy, though the latter damages environment through high carbon emissions. But lately, the costs of solar energy have come down dramatically, partly because of innovations in manufacturing photovoltaic (PV) systems and partly due to innovative ideas to save on land costs. The latest that we are aware of is being installed at R4.99/kWh right in the heart of Delhi at India Habitat Centre, without any subsidy from the government. This is cheaper than thermal energy based on imported coal from Australia. Therefore, wisdom lies in scaling up solar energy with all the speed and skill that India can muster and unleashing a revolution of clean energy, saving millions of lives from ever increasing pollution from thermal sources.
The government is targeting the generation of 1,00,000 MW of solar energy by 2022, including the electrification (through off-grid solar power) of about 20,000 villages that have been completely deprived of electricity so far. But the costs they are counting on still range from R6.50-8/kWh. This cannot create enough traction for a demand pull revolution without substantial subsidy (about 30%) from the government. However, the manufacturing developments in this field and open bidding process, suggest that the cost can be brought down to less than R5/kWh, provided land is supplied by the government/consumer. Roof-tops of all large commercial, government, and residential buildings in polluting cities are the first natural choice to install solar panels. Delhi chief minister Arvind Kejriwal, who is reported to be trying to buy coal mines to provide power to Delhi—already the most polluted city in the world—should instead focus on converting Delhi to a solar city, saving people from respiratory and lung diseases, including cancer.
But rooftops alone may not be sufficient to meet the growing needs of energy. The MNRE has been taking some initiatives in this direction and targets the setting up of at least 25 solar parks in the country, with each holding a capacity of 500 MW and more, between FY15 and FY19. A 750 MW solar plant project in Rewa district, Madhya Pradesh, with 50% World Bank funding, is a step in that direction. It will generate power at R5.50/kWh, occupying about 1,500 hectare of land. Acquiring such large tracts of land is going to be increasingly difficult. So, one has to think innovatively to save on land. In this context, the MNRE is also looking to generate 100MW from grid connected PV installations atop canals by 2017. A 10 MW canal-top plant was inaugurated in Vadodara in January 2015 by UN secretary-general Ban-Ki-Moon. The plant is expected to generate about 16.2 million units in its first year, but the cost works out to R6.48-7 per unit. That is where we need to get innovative ideas to scale up in a cost-effective manner, with costs trimmed to below R5/kWh.
Looking around the globe, we find that in 2013, China installed about 12 GW of solar power which is by far the most installed by any country in a year. This is also more than the cumulative installation till 2013 in China itself. India currently records about 3 GW of installed solar capacity, having added about 950 MW in FY 14, mostly attributed to the state solar policies and renewable energy certificate (REC) scheme. If India wants to compete with China, we need to focus on 3Ss (a catch-phrase coined by prime minister Narendra Modi)—speed, scale, and skill.
Japan is practising ‘solar sharing’, an innovation credited to Akira Nagashima in 2004. It is based on the premise that beyond an optimal level, sunlight does not contribute to photosynthesis in crops. So, lightweight PV structures are installed above the crops grown in a given piece of farm-land, with sufficient spacing to allow air flow. In addition, it acts as a shade for cattle and also reduces the cost of irrigation by increasing the moisture retention level of the soil.
China has also been following a similar practice over rows of eggplants, but more substantial installations have been executed over ponds and shrimp farms. Solar panels installed above ponds and fish farms in Dali county in Shaanxi province generated 1,100 MW to power the local village as well as to sell to the local grid. Additional income source for farmers and the reduced need for land are two important features that make this an important innovative process to be potentially adopted in India, particularly in shrimp farms in states like Andhra Pradesh and other coastal states.
For water bodies, floating solar plants are also being attempted in the UK, Israel and Japan. Japan’s Yakamura dam will see the biggest floating plant in terms of output capacity once installation is complete in March 2016. It is quoted to offset about 8,000 tonnes of CO2 emissions per year. This innovation frees the surrounding land for agriculture, conservation and other development purposes.
India can take a leaf out of these experiments in Japan and China, taking solar panels to various dams, canal-tops, fish-ponds, large lakes, and agricultural fields with the states’ agricultural universities. Once the experiments show good results and stabilise, they can be extended to the farmers’ fields, giving the latter some rental for their land, without displacing or adversely impacting the crops productivity. This can help not only augment farmers’ incomes but also provide power to their pump sets, cold storages in rural areas, and homes in villages, transforming the entire rural landscape. That would be a true salutation to the sun empowering our daily lives!
Gulati is Infosys Chair professor for agriculture and Manchanda is a research assistant, ICRIER