FUTURE PERSPECTIVES ON USING OUR SUN
- A Negative Aspects of Solar Energy
- A. Mani Mekalai, Advocate, Madras High Court.
Introduction
Solar energy systems (photovoltaic, solar thermal, solar power) provide significant environmental benefits in comparison to the conventional energy sources, thus contributing, to the sustainable development of human activities. Sometimes however, their wide scale deployment has to face potential negative environmental implications. Without solar energy, life would not exist on Earth. The energy from the sun keeps the Earth warm in addition to sustaining life on the planet. Solar energy can also provide electricity and although solar power has numerous benefits, it also has disadvantages. These potential problems seem to be a strong barrier for a further dissemination of these systems in some consumers. Knowing the negative effects of solar energy can help you determine if it is the right choice for you.
Definition
Solar power's vast potential makes it one of the most promising sources of clean, renewable energy --- but like any energy source, solar is not perfect. Solar energy comes from the rays of the sun, called solar radiation. As it reaches the Earth, the energy can be converted into thermal heat and electricity. Thermal energy can heat water and spaces, while solar cells and solar power plants can convert solar energy into electricity. These forms of solar energy have many beneficial uses in homes and different industries, but they can also have disadvantages. It comes with specific benefits and drawbacks.
Important Solar Projects in India
Solar Radiation Resource Assessment stations have been installed across India by the Ministry of New and Renewable Energy (MNRE) to monitor the availability of solar energy.
The government of India is promoting the use of solar energy through various strategies. In the last budget for 2010/11, the government has announced an allocation of 10 billion (US$183.0 million) towards the Jawaharlal Nehru National Solar Mission and the establishment of a clean energy fund.
· Charanka Solar Park - Charanka village, Patan district, Gujarat.
· Dhirubhai Ambani Solar Park, Rajasthan.
· Shri Sai Baba Sansthan Trust , Maharastra.( world's largest solar steam system).
· Sivaganga Photovoltaic Plant, Tamil Nadu.
· B&G Solar Pvt Ltd - Mayiladuthurai, Tamil Nadu- (India’s First plant Commissioned under JNNSM scheme 10 June 2011).
· Solar Energy Policy- Government of Tamil Nadu.
· Kolar Photovoltaic Plan, Karnataka.
· Tata Power , Orissa.
· Amruth Solar Power Plant, Andhra Pradesh.
On 18 November 2009, it was reported that India was ready to launch its National Solar Mission under the National Action Plan on Climate Change, with plans to generate 1,000 MW of power by 2013. From August 2011 to July 2012, India went from 2.5 MW of grid connected photovoltaics to over 1,000 MW.
Negative effect of solar energy
Solar energy technologies are essential components of a sustainable energy future. Nevertheless, solar energy systems have some certain negative impacts on the environment just like any other energy system. Some of these impacts will be summarized in this section.
Land
A solar energy installation requires a large area for the system to be efficient in providing a source of electricity. This may be a disadvantage in areas where space is short, or expensive (such as inner cities).All utility-scale solar energy facilities require relatively large areas for solar radiation collection when used to generate electricity at utility-scale (defined for the Solar PEIS as facilities with a generation capacity of 20 MW or greater). Solar facilities may interfere with existing land uses, such as grazing, wild horse and burro management, military uses, and minerals production. Solar facilities could impact the use of nearby specially designated areas such as wilderness areas, areas of critical environmental concern, or special recreation management areas. A serious solar power application needs to utilize square kilometers of desert area. Thermal balance of this land space can certainly be affected by such an application. Also, additional heat might destroy a few species living in this kind of harsh environment. The clearing and use of large areas of land for solar power facilities can adversely affect native vegetation and wildlife in many ways, including loss of habitat; interference with rainfall and drainage; or direct contact causing injury or death. The location of solar panels can affect performance, due to possible obstructions from the surrounding buildings or landscape. So there we have the main disadvantages of using solar energy to generate electricity for our homes and businesses.
Water
Parabolic trough and central tower systems using conventional steam plant to generate electricity require the use of cooling water. This could place a significant strain on water resources in arid areas. In addition, there may be some pollution of water resources, through thermal discharges and accidental release of plant chemicals, although the latter can be avoided by good operating practice. Stand-alone parabolic dish systems require no water, other than for periodic cleaning of reflective surfaces and so they have little impact on water resources. In arid settings, any increase in water demand can strain available water resources. Use of or spills of chemicals at solar facilities (for example, dust suppressants, dielectric fluids, herbicides) could result in contamination of surface or groundwater. Solar cells do not emit any pollutants during their operations. But solar cell modules contain some toxic substances, and there is a potential risk of releasing these chemicals to the environment during a fire. Necessary precautions should be taken for emergency situations like fire. The possibility of an accidental release of the chemicals of the solar cell modules to soil and groundwater poses a great threat for the environment. The solar panel used for irrigation pump & extractions of safe drinking water is very expensive because it depends how much deep you are going for the water. Since the pump is already, very expensive it is not possible to use battery and as a result, the pumps could run as long as there is sunlight.
Environment
There are no global warming emissions associated with generating electricity from solar energy, there are emissions associated with other stages of the solar life-cycle, including manufacturing, materials transportation, installation, maintenance, and decommissioning and dismantlement. Most estimates of life-cycle emissions for photovoltaic systems are between 0.07 and 0.18 pounds of carbon dioxide equivalent per kilowatt-hour.Likewise, noise is insignificant in comparison to any other power option, such as the conventional, the wind power generation, and the gas turbines. The noise from the generating plant of large-scale schemes is unlikely to cause any disturbance to the public. Noise would be generated primarily only during the day; at night, when people are more sensitive to noise, the system is unable to operate. Provided that such schemes are not deployed in ecologically sensitive areas or in areas of natural beauty, it is unlikely that any of the above changes would be considered as significant. Central concentrator power systems could pose a danger to birds, but operational experience shows that birds avoid any danger area. Flying insects can also be burnt when flying close to the reflector’s area. The loss of the insect population is insignificant.
Visual
One person's beauty is another person's eyesore.There will be some visual impacts depending on the type of the scheme and the surroundings of the solar cells. Especially for applications on the buildings, solar cells can be used as a cladding material that could be integrated into the building during the construction phase. Solar cell applications after the construction phase of the buildings might cause negative visual impacts. For some, solar panels evoke positive feelings, even when set in a natural landscape. For others, the sight of a solar panel invading a pristine desert environment is gutting wrenching. It's largely a matter of opinion. In addition to the collector systems, the main visual impact would come from the tower of the central receiver systems. However, the atmospheric requirements for these systems point to their deployment inareas of low population densities. So provided that areas of outstanding natural beauty are avoided, visual intrusion is unlikely to be significant. Generally large facilities with numerous highly geometric and sometimes highly reflective surfaces, solar energy facilities may create visual impacts; Concentrating Solar Power (CSP) systems could potentially cause interference with aircraft operations if reflected light beams become misdirected into aircraft pathways.
Hazardous Waste
Solar photovoltaic panels may contain hazardous materials that could be released when a panel is damaged or disposed of improperly .Concentrating solar energy systems may also use potentially hazardous materials like oils and molten salts, creating the potential for spills.Many different potentially hazardous chemicals are used during the production of solar cells. The primary environmental, health and safety concerns are exposure to and inhalation of kerfs dust, a byproduct of sawing the silicon ingots into wafers, and exposure to solvents, such as nitric acid, sodium hydroxide and hydrofluoric acid, used in wafer etching and cleaning as well as reactor cleaning. Many of these solvents also pose a risk of chemical burns. Other occupational hazards include the flammability of silage used in the deposition of anti-reflective coatings. The most likely exposure route for factory workers is inhalation of vapors or dusts. Risks to surrounding communities include the release of hazardous gasses from an industrial accident or fire at the manufacturing facility. These hazards are regulated by a number of occupational and environmental standards as well as industry adopted voluntary best management practices. This process involves multiple potentially hazardous materials and byproducts that without proper safeguards can pose a significant risk to human and environmental health. Solar photovoltaic panels may contain hazardous materials that could be released when a panel is damaged or disposed of improperly.
Health
Solar energy heat systems generate energy in order to heat the air and water. They collect the solar power and generate chemicals, mainly silicon dust, in order to accomplish this. This can pose harmful risks to those that live in the building and can compromise their health if they are constantly exposed to silicon dust. Constant inhalation of silicon dust can affect your lung's efficiency and pose serious health risks. Since some of the milder symptoms of this syndrome are common and non-specific, such as headaches and restlessness, a person using the building may not even know his or her symptoms are caused by the solar system. Central tower systems have the potential to concentrate light to intensities that could damage eyesight. Under normal operating conditions this should not pose any danger to operators, but failure of the tracking systems could result in straying beams that might pose an occupational safety risk on site.
Suggestions for minimizing the impacts
Solar energy is increasing in importance as an alternative energy source. It has become indispensable today due to being an environmentally friendly and infinite energy source. But solar energy systems have some impacts on the environment. These potential impacts depend on the size and nature of the project and are site specific. Negative impacts of the solar energy systems could be minimized with appropriate measures.
· First, site choosing should be done carefully before application.
· Proper sitting decisions can help to avoid land disturbance and land use impacts.
· Solar cell utilization should be planned at the architectural phase and fitted to the building to minimize visual pollution.
· The control of the visual impacts is the use of color. Enough care should be taken for the usage of proper colors while assembling the solar cell modules.
· Roofs are the best areas for little buildings, and solar cell modules are good alternatives for glass cover on the sides of larger buildings, like skyscrapers.
In order not to cause visual burdens, solar modules should be used as construction material during the construction phase, and they should be applied totally integrated with the buildings. There are miscellaneous precautions that could be taken to minimize the environmental impacts of the solar energy systems. Because of the toxic substances used in the solar cell modules, it will be wise to increase the module efficiency and lifespan, and research the possibilities of recycling.
Conclusion
Above discussion has shed some light to the fact that solar energy is a very useful renewable source of energy which if explored and nurtured further with proper steps than can become the answer to the future for power or energy needs. Furthermore, we can all contribute to the environment by using solar energy thus erasing or trimming down various gas emissions which can endanger earth, in turn, the millions of people in it. There are also few disadvantages which should be kept in mind as well. But one thing for sure, solar energy is one of the oldest and one of the most effective energy sources which if used carefully, can help us emphatically. Now what we need is to recognize its worth and make the best use of it and for this purpose effective action by the government is very much needed. Hopefully future generations of inverter design will be better, though it will be very difficult to fully remove this radiation.