"Nothing is stronger than an idea when its time comes"

RN Malik
Two big ideas in energy sector are doing the rounds in print media these days. A. Generate enough  green power (hydro, solar, wind) to replace all thermal power plants and meet future energy needs without them.
B. Power Minister R. K. Singh says, "India will eventually be an electricity based economy. The energy needs will be met through electricity rather than through petroleum products. We will make electricity green. These are our long term goals. " In other words, we want to get rid of fossil fuels and meet all our power demand to be derived from renewable resources  to save environment, prevent climate change and save foreign exchange.. The two big ideas are fantastic ,feasible and even achievable but short on pragmatism. Let us discuss these in details.
A. Replacing all thermal power plants.
Presently electricity is generated from four sources i.e thermal power plants, hydropower stations, wind turbines and solar panels. Power generated from these sources is 210GW, 45GW, 20GW, 35GW (one GW is = to I000MW) respectively
One MW of thermal power equals six MW of solar power as it generates only 4000 units per day. Thermal power plants are the mainstay of the power generation. Replacement of thermal power with green power will give following advantages.
I. One MW of thermal  power consumes 15 tonnes of coal per day to generate 24000 units of power. So all thermal power stations are consuming 3.0 million tonnes (mt) of coal daily which is carried by large number of goods trains from the coal mines. As a result coal constitutes 80 percent of freight load of goods trains. Replacement of thermal power will make 80 percent goods trains off the tracks giving much needed relief on busy routes.
2. Burning of 3.0 mt of coal daily produces huge volumes of carbon-dioxide( green house gas) besides other toxic gases like sulphur-dioxide and nitrogen oxide and ultra fine coal dust. Emissions of CO2 gas causes global warming followed by climate change. Other gases and coal dust cause serious air pollution affecting human health. These gases also cause acid rain.
3. Thermal power plants also produce huge quantities of fly ash causing lot of disposal problems.
4. Consumption of coal at this rate will exhaust the total coal reserves of the country in 90 years. Also it is becoming extremely difficult for Coal India Ltd. to mine so much coal daily to feed all the thermal plants.
Now the billion dollar question is how to generate alternate renewable sources of green energy to replace the thermal power entirely. Let us discuss one by one.
Hydropower
Brahamputra river Basin alone has the potential to generate 70000 MW of power with a power load factor of 80 percent. This will be possible if there is uninterrupted flow of funds and various clearances are secured quickly. But it is easier said than done because seeking environmental and forest clearances is a Herculean task. Rivers in Himachal and other hilly States have a potential of generating additional 50000 MW of hydropower. Presently cost of generating one MW of hydropower is Rs. 10 crore and gestation period of a normal hydropower plant is 8 years. Rate of hydro power development during last three decades has been minimal. Work on 2000MW Subansiri hydropower project is held up for the last nine years. So one cannot forecast when the target of developing 1.2 lac MW of hydropower will be met.
Wind power: Wind power turbines are economically viable only if wind velocity is more than 5.km per second and is available for at least 8 hours in a day. According to various surveys, hardly 10000 MW more wind power is left for generation along the coastline. Accordingly we cannot rely upon wind power to replace the thermal plants anymore. Also all the turbine manufacturing companies are under heavy debts.
Solar Energy: Solar energy has unlimited scope for development in our country. This is because we have 300 clear sky days in a year, highest solar radiation incident in Thaar desert of Rajasthan and  gestation period of solar projects is much less. A 100 MW power plant can be set up in six months. Presently, the cost of solar power beats other conventional modes of power generation. Use of solar energy for cooking and water heating is equally important to reduce demand on power consumption.. It's main limitations are  big requirement of land (27acres per MW of thermal power) , small number of units manufacturing  solar  panels within the country ,the quality or life span of solar cells imported from China not very ensuring and problem of disposal of huge number of solar panels and batteries after the life span of 25 years.
Presently we have 2.0 lac MW capacity thermal power plants in the country. NTPC is also adding 5000 MW capacity every year. If all goes well, replacement of thermal power with green power will take  15 years. By that time power demand will increase by another 75000 MW of power. 50000 MW capacity thermal power plants located near coal heads need not be replaced as these will also be needed to cope with peak loads. . We can safely assume to generate 50000 MW of hydropower during next 15 years. So finally 1.75 lac MW of thermal  power (equivalent of 1050 lac MW of solar power ) need to be replaced with solar power plants. 2.0 lac MW can be developed with the help of rooftop solar panels. Balance 8.5 lac MW of power is to be generated in large sized solar parks. These parks will require  38 lac acres or 3600 square miles of land. Can the government acquire so much land is again the billion dollar question.
NTPC and Solar Energy Corporation are already having negotiations with private power producers to set up 5 ultra .mega power plants of 28000 MW capacity three in Rajasthan (Barmer, Jaisslmer, Bicaner) and two in Kachh district of Gujarat . Indian Railways (IR) has also decided to set up solar panels with a total capacity of 15000 MW in unused land along the 50000 km railway tracks. Process of installing rooftop solar power panels in India is still very much in nascent stage. Also capacity addition of solar power plants is only 8000MW annually. The target of developing 1.75 lac MW green power by 2023 as announced by the Govt. of India too seems to be a distant dream.
B. Use of electricity in transport sector-:
90 percent of the transport sector runs on oil i.e. petrol, diesel . 40 percent trains and metro rails use electricity for traction. India is importing 135 million tonnes of crude oil from different countries at a huge cost. Therefore it is the endeavour of the government to use electric energy in the transport sector as much as possible firstly to save valuable foreign exchange and secondly to reduce air pollution. For example, if all people start using electric cars, the air quality index in all the towns will be reduced by at least 60 percent and all big cities would no longer become the gas chambers. We cannot use electricity  for running trucks, tractors and even buses. But if all railway tracks are electrified with increased share of freight load, metro trains become the mass transport in cities and all cars and three wheelers run on electricity, all generators eliminated and farmers use solar pumps for irrigation, then oil import will be reduced by 70 percent. But this electric traction of vehicles and trains will require additional generation of 50000 MW solar power which again will have to be taken care of by solar power. Development and use of solar cars will further reduce the requirement of separate solar power plants. To replace all the cars, three wheelers and two wheelers with electric one is a very difficult proposition. Electric car manufacturing has taken roots in India. Mahindra is producing 2000 cars annually.  Running cost per km of electric cars is only one rupee against Rs. 5.5 in case of petrol or diesel cars. But only sustained and aggressive campaign in favour of e-cars together with government fiats can achieve the necessary replacement.
Possibility of achieving goals.
I. It is possible to shut down thermal power plants of 2.25 lac MW capacity provided the government is able to acquire enough land both for solar and hydro power plants, secure quick various clearances and arrange uninterrupted flow of funds. Then replacement can be achieved in fifteen years.
2. NTPC should be asked to develop hydropower as well in collaboration with NHPC.
3. Government should form a policy to popularise e-cars and phase out cars using fossil fuels.
If the governments( Centre and states) are able to replace the use of fossil fuels with green power, then it would be the greatest revolution in the history of energy sector.