This is first of two parts article by Navaratna Srinivas Rajaram 

India may be on the brink of an energy famine. Solar power used in conjunction with existing power plants and the proposed river linking network can lead to an energy revolution that can double India’s energy production. Karnataka is particularly well situated to take advantage of the solar potential.

Learning from history

Canal-top solar plant on a Narmada branch canal

Fifty years ago it was widely believed that India would never be able to feed its people and mass starvation was something the country had to live with. In fact, in 1961 India was on the brink of mass famine. M.S. Swaminathan, then advisor to the Indian government recognized that ad-hoc solutions like increased grain imports would not do, and a permanent solution had to be found to India’s chronic grain shortage. Seeking drastic improvements in India’s agricultural production, the Government, with the collaboration of the Ford Foundation started a pilot project in Punjab to demonstrate that higher yields were possible using special varieties of wheat with better agricultural practices.

The experiment was soon extended to rice by adapting IR8— a variety of semi-dwarf rice developed by the International Rice Research Institute in Philippines. By 1968, Indian agronomist S.K. De Datta had shown that by combining the IR8 seeds with proper use of fertilizers and appropriate irrigation methods, it was possible to more than double the yield per acre. From a near famine situation in 1961, India by 2006 had become one of the world’s largest rice exporters shipping 4.5 tons in that year alone. This is now hailed as the Green Revolution.

In energy production, India stands today where it stood with regard to food grains production in 1961. Most cities face scheduled and unscheduled power outages while in rural areas, one would be lucky to receive even a few hours of electricity a day. Luxury apartments invariably include diesel power generators to deal with power outages. They burn diesel inefficiently and foul the atmosphere. As demand for electricity increases, more fossil fuels like coal and oil get burnt putting a strain on India’s limited coal supplies and adding to the oil import bill.

Let there be no illusions, the country is on the verge of an energy famine if not already in it. Politicians and the media can afford to ignore it only because they live in luxurious isolation from the suffering public. They can engage in political gimmicks and peddling trivia, while the people suffer and they live in luxury. One has only to visit small towns and villages to see the real situation.

What the situation demands is an energy revolution on the scale of the Green Revolution that has made India a surplus state in food grains, and the White Revolution that created abundant milk supplies. Thanks to solar this is now possible. Thanks to advances in solar power technology and the ready availability of inexpensive solar cells, it is now possible to think of doubling the generating capacity of many existing power plants, especially hydroelectric plants.

Linganamakki backwater suitable for soalr plant

While India is poor in fossil fuels, it is extremely rich in solar, more so than any other country of comparable size including the U.S. and even China. The important thing to note here is that the problem is not lack of supply— for the sun delivers many times more energy than we need or we can use, but its conversion into usable electricity. Scientists have calculated that 5000 trillion kWh energy is available over India’s land area, with most parts receiving from four to seven kWh per sq meter per day.

There are two ways to look at this: any solar plant only requires an area that receives sunlight; as a corollary, any area that receives sunlight but is not being used for solar power generation is wasting solar energy. Worse, this energy is heating living areas that now require cooling by energy consuming equipment like coolers air conditioners.

Harvesting solar

The science behind solar power is well understood. The heart of a solar plant is the solar cell or the photovoltaic cell. Unlike the familiar lead acid battery which is an electrochemical device, the photovoltaic cell is a solid state electrical device that converts light energy directly into electricity. The photovoltaic effect is related to the photoelectric but not the same. In the photoelectric effect electrons are emitted from the surface when exposed to light. In the photovoltaic effect electrons are not just emitted but transferred between different bands within the material.

This transfer of electrons between bands leads to the buildup of a potential difference (voltage) between the two electrodes. Assemblies of solar cells are used to make solar modules which can convert energy from sunlight. Multiple modules are assembled together in such a way as to lie within in a single geometric configuration (like a plane) to create a solar panel. A solar panel is essentially a power plant that uses sunlight as fuel. It is more properly called a solar power plant. A solar power plant installed in conjunction with a hydro power plant can double its generating capacity as well save the precious water stored in its reservoir. Here is how.

Solar farm

Every hydroelectric plant has a large reservoir storing water to drive its turbines. The reservoir covers hundreds and even thousands of acres of land that receives abundant sunshine. This sunlight can be tapped to supplement the generating capacity of the power plant. Solar panels mounted on the reservoir would convert sunlight into electricity and feed into the same power grid as the hydro generators.

This means the generators would not be drawing any water from the reservoirs when sunlight is adequate for solar panels to feed the grid. Thus the water stored in the reservoir would last much longer. This calls for the installation of solar panels, possibly floating, on the surface of the reservoir. These would not only feed the grid and make the stored water last longer, but also reduce evaporation by acting as a shield. Karnataka with its abundant hydroelectric resources is especially well suited to reap the benefits of solar.

Solar power technology has reached the point that it is viable on a commercial scale. A solar plant can be installed anywhere—on land or on water—on which the Sun shines. Any vacant area on which the Sun shines that is not being used for solar power generation can be seen as wasted space. This has given rise to the concept of harvesting solar energy by turning agriculturally unproductive land into ‘solar farms’. The practice is becoming particularly popular in the Western United States where the land is poor but sunlight is abundant (though not as abundant as in India).

India has little choice but go solar on a large scale. The U.S. experience suggests that with currently available technology, solar panels can convert over 10 percent of the Sun’s energy into usable electricity. This comes to .60 to 1.05 kWh per square meter and has been achieved on a commercial basis in solar farms in the U.S. India should be able to do better because the light intensity is greater. Nonetheless, it gives us a quantitative figure that can be used to arrive at technical and economic estimates.

The U.S. experience suggests that value added to otherwise unproductive land by solar plants can be one of the major incentives for land owners to turn to ‘solar farming’.  The U.S. has vast tracts of desert and semi-desert land in states like Texas, California, Nevada, Arizona and others. Some land owners even in less arid areas like Ohio are beginning to switch from agriculture to solar farms. They are attracted by the prospect of a continuous income from a one-time capital investment with little or no annual expenditure. A solar farm installation company in California notes:

“Solar farming is the process of turning unused or underused land into an electricity production farm. Solar farming allows individuals with vacant or otherwise unusable land to make a very good return on investment. Imagine making 12% or more guaranteed return for 30 years with no out of pocket money and cash flow positive from day one.”  Utilities (power companies) typically sign a 10 to 20 year power purchase contracts with solar farm operators. The going rate for PG&E, which supplies power to part of California, buys power from solar farm operators at $0.15 to $0.18 per kWh. At these rates a 5 acre parcel can generate about $300,000 profit per year.

The economics in India may be different but can easily be worked out. It is also worth noting that unlike in real estate development or setting up a manufacturing plant, a solar plant does not ‘consume’ the land: solar panels can be installed at a considerable height from the ground and do not interfere with ground level activities. For example, there is no technical reason why solar panels cannot be installed over a shopping mall which can continue to function as a shopping mall.

To exploit solar power on a large scale, a sophisticated grid will have to be set up at the state and eventually national level even while maintaining a high degree of decentralization. Here is where India’s previous experience with the milk grid combining local autonomy with a national grid using cooperatives can prove valuable. Tribhuvandas Patel who conceived India’s milk revolution recognized that milk unlike food grains cannot be stored over long periods and a network of cooperatives was the answer.

River network and solar network

Like milk solar (and wind) power also cannot be stored indefinitely. In hydroelectric plants we store power in the form of water in reservoirs which we draw as required for running generators. Adding solar plants saves this water. But a power grid can operate like the milk cooperative grid, matching supply and demand. The management and distribution of solar power grid may prove a greater challenge than solar power generation. But thanks to what is happening in Gujarat, we may soon be able to learn how to do it.

In a bold initiative, the Gujarat Chief Minister Narendra Modi has built and dedicated to the nation a solar power plant that has an installed capacity of 605MW in the solar park at Charanka village in Patan district of Gujarat. Of this total, 214MW of it is already operational making it the world’s largest photovoltaic plant. Spread over 3,000 acres in the dry, remote region of the State, it is a pointer to how agriculturally unproductive land can be made productive by ‘harvesting’ solar power. The Karnataka Government has announced a similar project in a village in the arid part of Bijapur district. This could be extended to other parts of the state also.

In India land is always in short supply though there is no shortage of agriculturally unproductive land that can be turned into productive solar farms. The Government in Gujarat has begun a project to use sections of the Narmada Canal for solar plants. A multi-purpose pilot project generating one megawatt of electricity from solar panels mounted above the Narmada branch canal was recently dedicated to the nation by Chief Minister Modi. This approach will spare valuable land that would otherwise be needed if the solar power project were land-based. In addition, panels, by acting as heat shield will save a huge quantity of water in the canals from evaporation.

This appears to be a unique innovation that has not been tried in the U.S. or anywhere else. It has considerable potential and can be used in irrigated and agriculturally productive areas where land cannot be spared for solar farms. This writer has suggested to the Karnataka government that the Vishweshwarayya canal in the Mysore and Mandya districts as well as several reservoirs in the area be converted into multi-purpose irrigation and solar projects. To begin with, ‘overhead solar farms’, as we may well call them, can be extended beyond canals to lakes and reservoirs also where the water loss due to evaporation is appreciably greater.

Opportunity squandered

Unused land near Mysore suitable for solar plant

Viewing solar farming as a multi-purpose program can be made national benefits by extending it to the river linking project that has just been mandated by the Supreme Court. This will mean the joint development of a solar power grid to go with the national river grid. If undertaken, this could prove to be one of the largest public works programs in history, comparable in scale to the U.S. Interstate Highway program under President Dwight Eisenhower. The proposed solar-river linking project would eventually yield benefits in flood control, irrigation, river transportation and power generation.

India squandered a great opportunity to develop the necessary infrastructure by opting for a populist program like National Rural Employment Guaranty Act (NREGA), instead of a public works program like river linking which might have come in handy today. NREGA is inspired by the 1960s era failed European welfare state idea. In India today as in Europe 50 years ago, it has created artificial labor shortages. Europe tried to overcome its labor shortages by importing workers from Third World countries leading to social and political tension.

On the other hand, a public works program of river linking with solar grid would generate employment at all levels including tourism and sports made possible by waterways, reservoirs and added power capacity. Further, unlike the ill-conceived NREGA which has only created labor shortages while being a huge drain on the economy, these would be productive jobs that would contribute to the national economy. The scientific, engineering and management experience acquired in the process would be of great value in future projects.

Both the technology and the methodology already exist to wean the country away from its excessive and ultimately infeasible dependence on fossil fuels. The science behind solar power is not new and constantly improving. What will be new is the design and implementation of a multipurpose grid of linked rivers and solar plants. This will call for political leadership and management talent of the highest order. India has no choice but meet the challenge; otherwise the future is bleak. Gujarat has already shown how it can be done.

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Dr. Navaratna Rajaram began his career with Tata Power Company who went on to spend over twenty years in the U.S. academia and high technology industry including NASA. He is now an independent researcher based in Bangalore, India and Boston, U.S.A.