Renewable Energy- Nizar

Renewable energy Prospects and Problems -MOHAMMED NIZAR.N The ever increasing price of fossil fuels exepted with high pollution caused by plans using fossil fuels has made the world concern about the very feature of our planet. For instance, economic activity in countries across the world which were depended heavily on imported petroleum and petroleum products was thrown out of gear by a sudden increase in petroleum price since 2000. Although the supplies of these fossil fuels such as coal, oil, and natural gas are vast out they are not unlimited. And more important, the earth's atmosphere and biosphere may not survive the environmental impact of burning such enormous amounts of these fuels. Carbon stored over millions of years is being released in a matter of decades, disrupting the earth's carbon cycle in unpredictable ways.

There is thus increasing

recognition of the role of renewable energy in ensuring energy security, sustainable development, decentralized energy supply and growth without Renewable energy? Now what is renewable energy? Why is everyone out there concerned about the future of renewable energy? Well, the answers are not as tough as we would have expected, nor do they require a lot of action in order to succeed. Our planet is dependent upon us to keep it thriving, and the best way to do that is to switch over to renewable energy. Renewable energy is energy generated from natural resources—such as sunlight, wind, rain, tides and geothermal heat—which are renewable

(naturally replenished). Renewable energy technologies include solar power, wind power, hydroelectricity, micro hydro, biomass and biofuels. According to IEA, "Renewable energy is derived from natural processes that are replenished constantly. In its various forms, it derives directly from the sun, or from heat generated deep within the earth. Included in the definition is electricity and heat generated from solar, wind, ocean, hydropower, biomass, geothermal resources, and biofuels and hydrogen derived from renewable resources."

Renewable energy from all sources accounts for only about 8% of global energy production. Nuclear makes up another 6% of global energy production. This leaves about 86% of global energy coming from fossil fuels, which are both non-renewable, and also the major cause of global climate change. Renewable energy sources 1. Wind Wind power is the conversion of wind energy into a useful form, such as electricity, using wind turbines. At the end of 2007, worldwide capacity of wind-powered generators was 94.1 gigawatts. Although wind produces about 1% of world-wide electricity use, it accounts for approximately 19% of electricity production in Denmark, 9% in Spain and Portugal, and 6% in Germany and the Republic of Ireland (2007 data). Globally, wind power generation increased more than fivefold between 2000 and 2007. Wind energy has a huge potential for electricity generation. The power output of a turbine is a function of the cube of the wind speed, so as wind speed increases, power output increases dramatically. Areas where winds are stronger and more constant, such as offshore and high altitude sites are preferred locations for wind farms. India ranks fourth amongst the windenergy-producing countries of the world after Germany, Spain and USA. More than 95% of installed capacity belongs to Private Sector in seven states. It is learnt that Tata power would be investing Rs. 500Crs for additional 115 MW wind project in Gujrat and Karnataka states. The order for the turbine have already been placed .This project shall be in addition of

85 MW wind power capacity of the company already have in Maharashtra state. The Central Ministry and several State Nodal Agencies encourage growth of Wind Energy Sector through financial incentives and policy support 2. Solar Electricity "Solar energy" refers to energy that is collected from sunlight. Currently, solar electricity generation accounts for less than 0.01% of total Global primary energy production, but like wind it is growing very rapidly. Generation of electricity from the sun can be accomplished either by concentrating solar heat and using steam to generate electricity, or using solar photo-voltaic panels, the majority of the growth is in the latter technology. Solar photo-voltaic panels are undergoing a technology revolution, with many emerging companies and technologies competing for market share. As regards solar energy, India had designed, developed, manufactured, installed in the field, and maintained around one million solar photovoltaic cell (SPV) systems by the end of March 2005, the largest number in any country. There are some 30 types of SPV systems — for rural homes and street lighting, for pumping water for drinking and irrigation, for community TV sets and rural telephone exchanges, wireless links to interconnect exchanges, satellite communication terminals, and to power the electronics on offshore oil production platforms. Optical fibre communication systems, anti-corrosion systems for oil and gas pipelines, and chargers for backpacked wireless communication sets for the Army are also covered by SPV systems. Besides, SPV systems are used in vaccine storage refrigerators in

rural primary health centres (PHCs), railway signals, and warning systems at unmanned railway-road intersections. There are some 19,000 such intersections along the country's railway network — a huge market for the SPV companies. The country's annual production of solar cells and modules is currently around 70 MW by eight manufacturers. The country's two leading SPV manufacturers — the public sector Central Electronics Limited (CEL) and Bharat Heavy Electricals Limited (BHEL) — are currently engaged in expanding their production capacities. There is huge opportunity for investing in this sector because the energy is completely renewable. The government had announced a generation-based subsidy of Rs 12 per unit for solar photovoltaic and Rs 10 per unit for solar thermal generation. 3. Hydroelectric power Hydro electric power uses the force of moving water to produce electricity. Hydropower is one of the main suppliers of electricity in the world, but most often in the form of large dams that disrupt habitats and displace people. A better approach is the use of small, "run of the river" hydro plants. The Indian government considers hydropower as a renewable economic, nonpolluting and environmentally benign source of energy. The exploitable hydro-electric potential in terms of installed capacity is estimated to be about 148,700 MW (See Table ) out of which a capacity of 30,164 MW (20.3%) has been developed so far and 13,616 MW (9.2 %) of capacity is under construction. In addition, 6,782 MW in terms of installed capacity from small, mini and micro hydro schemes have been assessed. Also, 56 sites for pumped storage schemes with an aggregate installed capacity of

94,000 MW have been identified. The government expects to harness its full potential of hydropower by 2027 with a whopping investment of 5,000 billion Rupees.

With the economic liberalisation, the Indian government also opened up the doors in 1991 to private companies for the setting up of private hydropower projects. However, so far only about 910 MW has been commissioned by the help of private players, which constitutes less than 3 percent of the total installed hydropower capacity. The present major private developers are Malana Power Company Ltd., the Jaypee Group and S. Kumar Group. Seeing the vast potential present in the hydro power generation, Jaypee ventured into private power generation on a “Build, Own, Operate” (BOO) basis. So far Jaypee has the distinction of participating in 54% of new hydropower projects under India’s Tenth Five Year Plan. Also, the Indian government is encouraging development of small hydro power (SHP) projects in the country because small and mini hydel projects have the potential to provide energy in remote and hilly areas where extension of an electrical transmission grid system is uneconomical.

*load factor is a measure of output of a power plant compared to the maximum output it can produce 4. Ocean Power 4. (a) Tidal Power Energy can be extracted from tides by creating a reservoir or basin behind a barrage and then passing tidal waters through turbines in the barrage to generate electricity. Tide mills are actually a very old form of power, that was used along the coasts of western Europe in the Middle Ages, and was only abandoned with the initiation of the fossil fuel era. In modern times, a tidal dam was built across the Rance estuary in Brittany, France, in the 1960’s. This project has an installed capacity of 240 MW, and has operated successfully for over thirty years. The cost of tidal generation is higher than traditional hydro-electric and can have impacts on marine estuarine environments. Deep marine currents, which are largely driven by tidal movements, offer a very stable energy source with low environmental impacts, but the technology has been very little studied. This type of generation is most comparable to wind, but has the advantages of predictability and high power-output per size of turbine. The future of tidal power is uncertain, but likely to grow. Since India is surrounded by sea on three sides, its potential to hamess tidal energy has been recognised by the Government of India. Potential sites for tidal power development have already been located. The most attractive locations are the Gulf of Cambay and the Culf of Kachchh on the west coast where the maximum tidal range is 11 m and 8 m with average tidal range of 6.77 m and 5.23 m respectively. The Ganges Delta in the Sunderbans in West Bengal also has good locations

for small scale tidal power development. The maximum tidal range in Sunderbans is approximately 5 m with an average tidal range of 2.97 m. The identified economic tidal power potential in India is of the order of 80009000 MW with about 7000 MW in the Gulf of Cambay about 1200 MW in the Gulf of Kachchh and less than 100 MW in Sundarbans. The Kachchh Tidal Power Project with an installed capacity of about 900 MW is estimated to cost about Rs. 1460/- crore generating elctricity at about 90 paise per unit. The techno-economic feasibility report is now being examined. 4. (b) Wave Power Wave energy has only been harnessed in a scattering of pilot projects around the world, without any major commercial application to date. However, that will likely change over the next few years, with projects potentially coming on-line in Portugal, The United States, South Africa, and elsewhere. Wave power is most commonly harnessed several km out from shore, where the waves are most consistent. Often some form of buoy is used, which generates electricity as it bobs up and down, however a long snake-like structure has also been created by one company that generates power as the wave moves along it. The Indian Wave Energy Program started in 1983 at the Indian Institute of Technology, Madras. Early research led to the conclusion that the Oscillating Water Column (OWC) type of device was most suitable for Indian conditions and a 150 kW pilot plant was actually built and commissioned in October 1991 in the breakwater of the Vizinjham Fisheries

Harbor

near

Trivandrum

in

Kerala.

In 1993 the National Institute of Ocean Technology was established within the IIT-M campus and it took over the wave energy program. NIOT

continues research on wave energy as part of its overall mandate to exploit India's ocean resources. While an improved model was again installed at Vizinjham in April 1996. The Maharashtra Govt is setting up a small tidal power plant in 2 coastal villages in Ratnagiri district. A pilot of sorts it will produce between 15 to 20 kW of power when it goes operational this May. The project costs about Rs 4.5 million ($100,000), and similar projects are underway in 15 other villages. The hope is that the success of this project could lead to a similar project with a capacity of 250 kW. 5. Biofuels Biofuels are an extremely fast-growing, but also very controversial form of alternative energy. Two key questions remain unclear regarding the use of biofuels: do biofuels provide more energy than it takes to grow, harvest and transform them? And, is there enough land available for biofuels to grow any meaningful quantity? The answers to these two questions are linked. Current biofuel crops and processes are extremely inefficient. For instance, the U.S. department of energy concludes that "the 'net energy balance' of making fuel ethanol from corn grain is 1.34; that is, for every unit of energy that goes into growing corn and turning it into ethanol, we get back about one-third more energy as automotive fuel." However, other studies, including a 2005 study from a Cornell University researcher, conclude that it actually takes more fossil fuel energy to create ethanol than you actually get back in the resulting fuel. In short, according to these studies, using a litre of ethanol actually contributes more to global warming than just using a litre of gasoline. Biodiesel has similar controversy, although the energy returns are somewhat better. Also, According to the USDA, amount of the total corn

crop consumed to make ethanol will rise from 12 percent in 2004/05 to 23 percent in 2014/15. This will likely drive up the price of corn used for food, and even while using almost a quarter of the U.S. corn crop, ethanol will make up a fairly small proportion of the fuel used in the United States. The food to fuel problem is the strongest argument against the current generation of biofuels. A report from PotashCorp on this trend in agriculture reads as follows: “With the growing demand for food and now a surge in the production of biofuels, the annual increase in grain consumption has grown from its historical rate of 1.2 percent to 2.0 percent. That has led to a widening gap between consumption and production – one that would become even more pronounced if production failures or other supply disruptions occur." Biofuels only have a meaningful future if the means of production are shifted away from agricultural crops. 6. Hydrogen Hydrogen fuel can be implemented as a renewable energy medium with immense potential. When utilized properly, it has the potential to entirely replace fossil fuels altogether. Hydrogen is not an energy source, it is an energy carrier, and potentially a means of storing energy. Currently, most of the world's hydrogen is produced from natural gas by a process called steam reforming. Using this process, Carbon Dioxide is still released leading to climate change, and non-renewable resources are still consumed. There is another way to make hydrogen, however, which is the use of electricity to break water down into hydrogen and oxygen. If this is done using renewable

energy sources, the 'hydrogen economy' is born. Hydrogen can be used to very efficiently generate electricity in fuel cells. Fuel cells are based on the chemical reaction in which hydrogen and oxygen combine to make water, but instead of letting the reaction happen explosively, it happens in a controlled process that generates large amounts of electricity and relatively little heat. Because it can be stored and transported without losses, hydrogen may be an important intermediary in going from our fossil-fuel economy to one based on renewable energy, and because it is a high-energy fuel it may be particularly important in tranport, although batteries may instead fill this role. More and more research is going on developing new technologies in this area. 7. Geothermal Geothermal energy is the energy of the core of the earth. This energy is replenished by the slow decomposition of nuclear isotopes in underground rocks. The core of the earth is at about 4,000 degrees Celcius, and hot springs near the Earth's surface can reach 350 degrees Celcius. This energy can be used to heat homes or generate electricity in areas of geological activity where it is most readily available. Today, 22 nations are generating geothermal electricity, in amounts sufficient to supply 15 million houses. Geothermal energy is also used as a direct heating source in areas where it is available. Most modern geothermal electricity plants use a binary technology, where a heat exchanger transfers the heat from subsurface water to a liquid with a lower boiling point than water, which is then used to generate electricity. This has the advantages of no emissions to the atmosphere and low consumption of water, and allows power generation from lower temperature reservoirs. A second, unrelated type of geothermal

heating system uses the relatively small amounts of heat in the ground in non-geologically active areas to generate heat in a system quite similar to a refrigerator. These heat pump systems, while relatively efficient, are costly to install and still require significant amounts of electricity to run. Current penetration of renewable energy technologies in the market place: The penetration of renewable energy into the energy system of human settlements on Earth is from one point of view nearly 100%. But, only 0.02% of this energy system is currently managed by human society. A larger part of this renewable energy is in the form of biomass energy, either in food crops or managed forestry providing wood for industrial purpose of for incineration(fire wood used for heat or cooking in poor countries or for mood-setting fire-places in affluent countries, residue and waste burning in combined power and heat plants or incinerators). Hydropower is a substantial source, but it is no longer growing due to environmental limits identified in many locations. Passive solar heating is a key feature of building design throughout the world, active solar heat or power panels are still at a very minute level of penetration. The thing is that it requires lot of spaces to set up. This also involves high costs. Also wind has both passive and active role. Passive use of wind energy for ventilation of buildings plays a significant role. And active power production by wind turbines is today a rapidly growing energy technology in many parts of reaching nearly 20% of total electricity provided is found in Denmark. India ranks among the windproducing countries of the world after Germany, Spain and USA.

Further renewable energy technologies, so far with small global penetration, include biofuels such as biogas and geothermal power and heat. the dominant energy sources are still fossil fuels, despite the fact that they are depletable and a cause of frequent national conflicts, due to mismatch between their particular geographical availability and demand patterns. Problems Renewable energy increases diversity of energy supplies and can replace diminishing fossil fuel resources over the long run. Their use in place of fossil fuels can substantially reduce greenhouse gases and other pollutants. While experts believe that many new markets could sustain even higher rates of renewable energy penetration, numerous barriers remain. The cost of renewable energy technologies remains high, although it continues to fall. Though the world has realized the need for the importance of renewable energy system there contribution to these areas are lower (see why are we still addicted to oil). Another disadvantage with renewable energy is that it is difficult to generate the quantities of electricity that are as large as those produced by traditional fossil fuel generators. Another disadvantage of renewable energy sources is the reliability of supply. Renewable energy often relies on the weather for its source of power. Hydro generators need rain to fill dams to supply flowing water. Wind turbines need wind to turn the blades, and solar collectors need clear skies and sunshine to collect heat and make electricity. When these resources are unavailable so is the capacity to make energy from them. This can be unpredictable and inconsistent. The current cost of renewable energy technology is also far in excess of traditional fossil fuel generation. This is because it is a new technology and as such has extremely large capital cost.

So a key strategy for market acceleration is by removing trade and investment barriers between countries with significant renewable resources. Global strategies for accelerating the market penetration and diffusion of renewable energies need to engage both developed and developing countries. Governments can employ a number of strategies to improve the competitiveness of renewable energy. Technology up gradation is also an important factor to be met.

Why are we still addicted to oil? In 2006 it was estimated that the cost to the US of the Iraq war will be between $1 trillion and $2 trillion, according to a report written by Joseph Stiglitz, a Columbia University professor who won the Nobel prize for economics in 2001, and Linda Bilmes, a Harvard budget expert. Many people now believe that the Iraq war was fought primarily because of the Iraq's large oil resources, and U.S. dependence on foreign oil. The result is a one trillion dollar invoice. But imagine if the same amount had been spent on renewable energy and energy efficiency. Consider, by contrast, that in 2006 all funding for renewable energy and any related scientific research through the U.S. Department of Energy was less than 10 billion dollars. Even multiplied over ten years, the total budget for renewable energy adds up to less than one tenth the cost of the Iraq war. Since the United States is seeking energy security, one speculates that investing 1-2 trillion dollars in renewable energy and energy efficiency might have got it there with a far

greater degree of permanence than the Iraq war, even had the war been

successful.

ACTIONS NEEDED  Governments should substantially facilitate the use—in an environmentally

sustainable

way—of

renewable

energy

resources through adequate policies and subsidies. A major policy step in this direction would include implementing clear price signals for avoided greenhouse gas emissions.  Governments should also promote research and development in renewable energy technologies by supplying significantly more public funding.  The private sector, aided by government subsidies, should seek entrepreneurial opportunities in the growing renewable energy market.  The S&T community should devote more attention to overcoming the cost and technology barriers that currently limit the contribution of renewable energy sources.  NGOs can assist in promoting the use of renewable energy sources in developing countries.  The media can play an essential role in heightening the general public’s awareness of issues related to renewable energy. Conclusion: In comparing the various forms of energy—coal, solar, and wind—there are pros and cons to each in such a unique way that no overall quantitative assessment can be made. What is most pertinent for the sake of the environment—and for species’ health—is the fact the emissions released from coal are severe, indeed. Using renewable energy would eliminate this problem entirely. However, the needs of people—especially those in developing countries—must be mixed into the equation for a realistic result to be obtained. Even China, completely aware of the problem at hand,

cannot simply switch energy forms if the alternative will not be able to securely sustain its people. Thus, for such developing countries, it seems that the only thing that can be done for the time being is to slowly offer alternatives, to give aid in implementing new forms of energy, and to suggest laws through international policy that will force the abatement of emissions. However, renewable energy does offer a great alternative to us. It is the answer for energy crisis. It is the answer to global warming. It is the answer to a more comfortable life. All but not least, renewable energy is our future.

REFERENCES:  Renewable Energy, by Bent Sorensen- edition 2004  ENERGY SOURCES: the wealth of the world, by Eugene Ayres, Charles A.Scarlott 

www.wikipedia.org



www.ecoworld.com



www.ourclimate.net



www.financialexpress.com/news



www.iea.com/textbase/subjectqueries



www.interacademycounsil.net/cms/reports



www.indiasolar.com



www.ucsusa.org/clean_energy



Renewable energy sources coming of age, Ashok Parthasarathi, The Hindu, 2005/08/17