Wind Power

Wednesday, July 1, 2009

Bringing Sustainability in Coal Mining Operations is need-of-the-hour

Bringing Sustainability in Coal Mining Operations is need-of-the-hour:

A. Introduction - The importance of sustainable development principles has been increasing within the mining sector over the past two decades. Early work focused mainly on mining metals and commodities other than coal and energy fuels. Because sustainability, however, is an important consideration for all human endeavors now, the coal industry has become active in sustainability efforts. A number of global coal mining companies have embraced sustainability as a key aspect of corporate philosophy.

Continued production of minerals and fossil energy fuels may not fit into commonly understood definitions of sustainability. Mineral and energy extraction and reclamation operations do, however, contribute significantly to sustainability through the benefits they provide to society, when they are conducted in a manner that supports sustainable economies, social structures and environments throughout all phases of mining, including closure. Significant progress can also be made through the inclusion of sustainability concepts in the original design of the operation, as well as in ongoing operations. Innovative engineering, mining and reclamation operations can be optimized through consideration of environmental and economic sustainability goals, side-by-side with traditional technical mining engineering considerations.

B. Abate hazards in coal mining areas by promoting reclamation - Coal mining operations can result in disturbances to the land surface that burden or adversely affect commerce and the public welfare by destroying or diminishing the utility of land for commercial, industrial, residential, recreational, agricultural, and forestry purposes, by causing erosion and landslides, by contributing to floods, by polluting the water, by destroying fish and wildlife habitats, by impairing natural beauty, by damaging the property of citizens, by creating hazards dangerous to life and property, by degrading the quality of life in local communities, and by counteracting governmental programs and efforts to conserve soil, water, and other natural resources. The predicted expansion of coal mining to meet the world’s growing energy needs makes it even more urgent to establish appropriate standards to minimize additional damage to the environment and to productivity of the soil and to protect the health and safety of the public. At the same time it is important to develop programs with associated funding mechanisms to restore the utility of land damaged by past mining.

For example, China has reported it has about 13.3 million acres “derelict” lands of which four million of those acres were caused by past coal mining. This adversely impacts nearly 1/10th of China’s total agricultural acreage. Although mining reclamation began in the early 1960s in China, it has not been consistently implemented and about 40,000 new hectares are presently being disturbed by coal mining activities each year. In India more than 80,000 people have to be shifted to safer places as they are residing in areas which are now considered unstable due to past unscientific mining and the coal mine fires endangering such areas. Large tracts of mined out/subsided areas of the past also require reclamation apart from dealing with fires in some of the old coalfields.

i. Goals and Objectives towards better Environmental Management - Mining becomes a temporary land use through programs of environmental management and land reclamation.
* Establish a nationwide program to protect society and the environment from the adverse effects of coal mining operations.
* Assure that the coal supply essential for any nation’s energy requirements and to its economic and social well-being is provided and strike a balance between protection of the environment and agricultural productivity and the country’s need for coal as an essential source of energy.
* Promote reclamation of mined areas left without adequate reclamation and which continue, in their un-reclaimed condition, to substantially degrade the quality of the environment, prevent damage of the beneficial use of land or water resources, or endanger the health or safety of the public.

ii. Management of topsoil for geo-environmental reclamation - Topsoil is an essential component for land reclamation in mining areas. It is seriously damaged if it is not mined out separately without being contaminated, eroded and protected. Systematic handling and storage practices can protect topsoil while in storage and after it has been redistributed onto the re-graded area. Removed topsoil should be reclaimed technically and its shelf-life period should be ascertained. Soil dumps of different age classes in the area were identified and analyzed critically to evaluate the deterioration of soil quality with respect to time, and compared with those of unmined areas. Changes in soil quality showed a continuous decrease every year and ultimately became biologically sterile. Biological reclamation is essential if the soil is to be stored beyond the shelf-life period.

C. Current Issues -
i. The future of coal extraction - It is widely recognized that coal is and will continue to be a crucial element in a modern, balanced energy portfolio, providing a bridge to the future as an important low cost and secure energy solution to sustainability challenges. Energy demand everywhere is expected to grow substantially. In emerging economy, most of developed and developing nations, almost every energy source is expected to grow, with coal, petroleum and natural gas dominating the energy mix. In these nations, electricity generation relies heavily on fossil fuels; coal is the dominant component which is expected to increase. As per estimation, overall, world use of coal is projected to grow by 44 % by 2025.

In addition, coal and crude oil can both be used as feed stock for conversion into liquid fuels and the choice depends on the price of feed stock. Energy economists maintain that coal liquefaction is viable for crude oil prices greater than $40 per barrel. Experts predict that Coal-to-Liquids (CTL) will be the largest contributor of “un-conventional” fuels.

ii. Corporate policies - The global coal and energy production industries have recently begun a major effort to identify and accelerate the deployment and further development of innovative, advanced, efficient, cleaner coal technologies. A number of coal producers in developed nations are also involved in sustainable development activities, including economic sup-port of communities and regions and environ-mental protection and restoration. These companies have corporate sustainable development policies in place that provide guidance for operations and some report annually on their contributions to sustainability. Challenges facing Mining industry for sustainable development are:
* Ensuring the long-term viability of the minerals industry,
* Control, use, and management of land,
* Using minerals to assist with economic development,
* Making a positive impact on local communities,
* Managing the environmental impact of mines,
* Integrating the approach to using minerals so as to reduce waste and inefficiency,
* Giving stakeholders access to information to build trust and cooperation,
* Managing the relationship between large companies and small-scale mining,
* Sector governance: Clearly defining the roles, responsibilities, and instruments for change expected of all stakeholders.

iii. Traditional mine design considerations - Most mine designs are based on traditional mining engineering factors, such as the quality of the commodity being mined, the geology, topography, hydrology, land ownership, geography, infrastructure, etc. Currently, environmental compliance and sustainability are considered in mine design and operation as a modifying factor to those designs.

iv. Optimization - A cursory review of the available literature on engineering optimization does not reveal any focus on mine design, environmental protection associated with mines or sustainability. Mathematical multi-criteria optimization approaches, however, have previously been used in resource management. Unfortunately, there is a paucity of literature about the practice.

As with any optimization problem, mine design optimization would need to consider all constraints, system parameters and characteristics and desired outcomes in order to build a useful and reliable model. Since optimization of mine design, and in particular coal mine design, to address sustainability along with other parameters has not been widely practiced, identifying the appropriate parameters for measurement and the mathematical or logical relation-ships between these parameters is not a trivial task.

D. Suggested approach - In order to optimize the design of coal mining and reclamation operations, traditional mining engineering considerations and environmental and sustainability goals must be accounted for simultaneously. It is essential to identify all of the parameters, relationships, constraints and desired outcomes related to the widely varying factors that contribute to mine design, as well as the additional factors that should be considered as a part of a new, sustainable design approach.

i. Parameters - For successful optimization of mine design, required parameters must be identified and measured as part of mine design and planning. To build an accurate model of those operations, data must be collected on ongoing operations. This data accounts for the modification of long-term designs as a part of permitting and the acquisition of information during mine operation. The design and operation of current coal mining properties should be evaluated by looking both at permitting documents and additional data which obtained from mining companies and other public and private sources. This data reflects the mining engineering, geologic, economic and other considerations currently integrated into the design and planning process.
It can then be determined how legal, policy, environmental protection and sustainability should be incorporated in mine design. Whenever possible, the effect of environmental and post-mining land use considerations on mine design and operation needs to be quantified in economic terms, so as to be on par with other engineering considerations.

ii. Relationships- Once sufficient data is collected, it will be necessary to determine if and how these parameters influence one another and the desired outcomes for the specific mining operation. These relationships may be apparent based on scientific, engineering or other considerations, or may require detailed statistical analysis in order to determine them. It may not be possible to state the precise interrelationships between numerous parameters, particularly given the lack of complete independence of many of them. It may be possible, however, to derive qualitative rather than quantitative models for those relationships.

iii. Desired Outcomes- In most cases, the ultimate desired outcomes are the profitability and long-term stability of the site. These are driven by corporate realities as well as the concern for long term liability. Coal mining is, after all, a business focused on profitability and long-term economic benefit for the shareholders or other owners. Additional out-comes for community economic benefits, enhanced environmental quality, and corporate image are also significant for many mining companies and in many locations.

The optimization approach must address the relative importance of these outcomes in order to weight them in the development of optimized models. For example, in an area with low avail-ability of safe drinking water, protection of hydrologic resources may prove to be of primary significance, and thus of higher weight in the models, since it will greatly impact the feasibility and long-term profitability of the operation as well as the post-mining health of the community.
The factors related to sustainability in the minerals industry, identified above, can serve as the basis for desired sustainability outcomes. The first factor, industry viability, is ad-dressed primarily through consideration of the economic profitability of an operation. Giving stakeholders access to information; defining the roles, responsibilities and instruments for change; managing the relationship between companies of different scales; benefiting local communities; and, promoting efficient use of minerals, are social factors which may be more difficult to measure and may not directly impact the design and operation of a specific mining property.

However, managing the environmental impact of mines and the control, use and management of lands are both more easily quantified and related to accepted practices and legal frameworks. Future work should focus on the parameters related to these goals. Many of these parameters may already be routinely measured as a part of environmental or other compliance mechanisms.

E. Nation’s Mission To Protect Environment by Enacting Laws– It is of national interest, Governments of every country should be dedicated to protecting the environment of the nation. In other words, to protecting the health and safety of the miner and to protecting the life, health, and property of citizens who are affected by mining or mining activities through the enforcement of suitable state mining and reclamation laws. The laws should ensure that the environment is protected during coal mine operations, and that lands mined for coal are adequately reclaimed after mining is completed. It allows alternative or experimental reclamation practices to encourage technological advances in mine reclamation and innovative post-mining land uses.

i. Environmental Impact Assessment (EIA) - Some form of Environmental Impact Assessment (EIA), and accompanying procedures for information disclosure, public participation and judicial or administrative review, have become widely adopted as part of the project and/or policy review process in most countries.

The US government introduced EIAs as an “action-forcing mechanism” to identify, assess, and mitigate environmental and human impacts of government actions in the United States. Since then, EIAs have spread to well over 100 countries, and have been enshrine in Principle 17 of the Rio Declaration, gaining worldwide legitimacy as a critical element of environmental management. EIAs have grown in both strength and scope and are now one of the premiere tools in environmental management in most countries. EIAs should address some of the basic factors listed below:

* Meteorology and air quality. Ambient levels of pollutants such as sulphur dioxide (SO2), oxides of nitrogen, carbon monoxide (CO), suspended particulate matters, should be determined. Additional contribution of pollutants at the locations are required to be predicted after taking into account the emission rates of the pollutants from the stacks of the proposed plant, under different meteorological conditions prevailing in the area.
* Hydrology and water quality
* Site and its surroundings
* Occupational safety and health
* Details of the treatment and disposal of effluents (liquid, air and solid) and the methods of alternative uses.
* Transportation of raw material and details of material and details of material handling.
* Impact on sensitive targets.
* Control equipment and measures proposed to be adopted including post-mining reclamation.

Preparation of environmental management plan is required for formulation, implementation and monitoring and of environmental protection measures during and after commissioning of projects. Planning for closure and reclamation should begin during the earliest stages of project development, before operations start at a new site, and continues throughout the mine life. Goal is to minimize the disturbance of land in all phases of the mine life and to provide a post-closure land use which is compatible with traditional uses or provides sustainable advantages to the local communities.

ii. Coal Mining Permit Process - Before commencement of coal mining operations, a mining and reclamation permit must be obtained from the Govt. departments. A coal permit should be issued when the mine operator submits an acceptable application and posts adequate bond to cover reclamation costs, should it be necessary for a third party to complete the reclamation process. The operator's permit application must include the requirements for legal and financial compliance, the safeguard of environmental resources, and an operation and reclamation plan. Before opening the site, the employees of the coal mining operation must be trained and certified in accordance with state and federal safety regulations. Mining practices, reclamation, and health and safety procedures are monitored on a regular basis by the Departments' field inspectors.

iii. Following goals, in general, should be accomplished through Permit Process -
* Reviewing permit, revision, field amendments applications for completeness and technical adequacy.
* Ensuring that adequate bond to complete reclamation is posted by the permittee.
* Conducting complete and partial inspections on coal permits as required by state and federal rules and regulations and the specific requirements of the approved permit such that non-compliance items are identified and appropriate abatement measures implemented.
* Conducting annual and mid-term permit reviews in compliance with statutes and regulations.
* Conducting bond release inspections in compliance with statutes and regulations.
* Conducting citizen complaint inspections in compliance with statutes and regulations.
* Gathering evidence and testifying at hearings as required by statutes and regulations.
* Conducting Student Outreach Programs at local area schools to provide students and teachers with a better understanding of the mining process.
* Receiving on-going training and information concerning current technical advances and trends in mining, safety, and reclamation.

F. Summary and Conclusion - It is widely recognized that coal is and will continue to be a crucial element in a modern, balanced energy portfolio, providing a bridge to the future as an important low cost and secure energy solution to sustainability challenges. In response, the global coal and energy production industries have begun a major effort to identify and accelerate the deployment and further development of innovative, advanced, efficient, cleaner coal technologies. A number of coal producers are also involved in sustainable development activities, including economic support of communities and regions, environmental restoration and social well-being.

The designer of coal mining operations needs to simultaneously consider legal, environmental and sustainability goals along with traditional mining engineering parameters as an integral part of the design process. The role of coal in the global energy supply mix makes this of primary importance. There is a need for research into the parameters for mining design that allow the building of models for optimization, the relationships between those parameters, and the desired outcomes that the system is being optimized to produce. In addition to quantifying the economic viability of the operation, a number of sustainability goals should be built into the model and the relative importance of those goals determined.

1. Energy Information Administration (EIA), 2007. Annual Energy Outlook 2007 with Projections to 2030. Washington: US Department of Energy, Energy Information Administration. in-dex.html accessed March 30, 2007.
2. Global Reporting Initiative (GRI), 2007. G3 Sustainability Reporting Guidelines. accessed March 30, 2007.
3. Gibson, R.B., S. Hassan, S. Holtz, J. Tansey and G. Whitelaw, 2005. Sustainability Assessment. London: Earthscan Publications.
4. International Energy Agency (IEA), 2004. World Energy Outlook 2004, Paris: Organization for Economic Co-operation and Development/International Energy Agency.
5. International Institute for Environment and Development (IIED) and World Business Council for Sustainable Development (WBCSD), 2002. Breaking new ground: The report of the Mining, Minerals, and Sustainable Development Project. London: Earthscan Publica-tions.
6. Stadler, W. (ed.), 1988. Multicriteria optimization in engineering and in the sciences. New York: Plenum Press.
7. Waddell, S. and B. Pruitt, 2005. The Role of Coal in Cli-mate Change: A Dialogic Change Process Analysis. Presented at the Generative Dialogue Project Launch Meeting, New York, NY, October 6-8, 2005.
8. World Coal Institute (WCI), 2007. Environment and Society.

Tuesday, August 5, 2008

Energy Mix Strategies for oil importing country – Important in the scenario of energy security and global warming:

Energy Mix Strategies for oil importing country – Important in the scenario of energy security and global warming:

A. We are aware of the problems of environmental pollution and the adverse consequences of global warming causing due to CO2 emission. To restrict environmental pollution, to mitigate the CO2 emission and rate of increase of CO2 concentration in the atmosphere, responsive long term energy mix strategies exploiting the maximum potential of non-greenhouse gas emitting energy sources need to be developed and implemented as rapidly as possible. The future energy mix will not only depend on environmental issues, but also will depend on technological, economic, supply, logistics and political factors. It is generally accepted that for many decades fossil fuels will continue to be the major energy source world over. Natural gas being the lowest fossil fuel greenhouse gas emitter will increase the share in energy scenario world over. Countries having or exporting fossil fuels cannot easily turn away from their use and likewise the industrially & economically dynamic countries of Asia such as China, Japan and India cannot radically shift from fossil fuels towards uncertain and currently costly renewable for their growing power needs.

B. National and regional factors are the most important in guiding country's energy mix. Percentage share of energy differ considerably today and they will in the future. For example, today China is more than 90% dependent on various forms of fossil fuels. On the other hand, France and Sweden have reduced their dependence on fossil fuels to less than 50% and 35% respectively by using nuclear and hydro-power to a great extent. Moreover, out of all the fossil fuels coal is the workhorse of global electric power sector and is used to generate more than half of the electricity world consumes. Coal is also world’s most abundant fossil fuel, with supplies projected to last almost 250 years or more. As coal-fired power plants generally produce the lowest-cost electricity and coal is abundant, most of the country’s economic and energy security depend on the continued use of the fuel.

C. Therefore, on the global level, it is difficult to make a policy decisions to foster a reduced reliance on fossil fuel. Decision makers are confused on how to proceed for country’s energy mix for the future as there is general support for cost effective energy efficiency techniques and on the supply side an endorsement of an increased use of renewable and sustainable energy sources. In fact, both the efforts are necessary at present; but ‘renewable and sustainable energy sources’ have limited potential over the near term. However, in the developed and industrialized countries, the significant energy efficiency gains and use of renewable energy sources have been seen over the past two decades, that changed the dependence on fossil fuels and energy scenario to a great extent on their industrial and residential front.

D. The supply potential from renewable energy sources, at present, is difficult to assess since they are only emerging technologies and currently not suitable for meeting large energy demand of a country. With differing relevance for the various renewable energy sources, technological improvements are needed and basic challenges exist in reducing costs, improving efficiency and reliability, solving energy storage problems and integrating the technologies into existing energy systems. In most of the developed countries many decision makers in the opinion that, non-hydroelectric renewable energy sources, such as solar and wind will not be economically competitive for large scale production in the foreseeable future and that they will play no more than a limited role in the decades to come. They opine that, even with adequate support and subsidies the share of such renewable energy sources could reach only 5-8% (including about 3% non-commercial energy share) of primary energy supply by 2020.

E. Fortunately, hydroelectric has already been extensively developed and in use in Europe and North America (some 50% of the estimated maximum economic potential). Its greatest potential lies primarily in Asia, South America and Africa, where the trend will likely be towards small capacity units as concerns grow about the damaging environmental and social impacts of large dams.

F. Energy security and implementing proper energy mix strategies for oil importing countries are very much crucial especially in the scenario of rapid industrialization. For those countries, in my opinion, renewable energy must be developed in parallel with nuclear power and a clean-up of coal-fired power station technology, if these nations are to meet increasing demand without relying on enormous and potentially debilitating natural gas imports. For a nation the provision of sufficient, affordable and secure energy is crucial for any modern economy. Many countries are facing the challenge of bridging the widening gap between energy supply and demand. At the same time, across the globe, those same economies are facing challenges such as climate change, limited resources and rising costs. Therefore, for oil importing countries, energy mix should shift more towards, nuclear power and clean coal technology.

G. There are very large amounts of remaining oil, gas and coal left in the world and in the absence of concerted government initiatives, it may take many years before alternative energy sources such as wind and solar become a significant part of the world’s energy mix. It is true that some renewable sources such as bio-fuels and wind have attained ten-fold production increases throughout the past ten years. However, global energy demand is increasing at such a rate that, if we ignore hydro-electricity, renewable energy - as a proportion of total energy supply - may well remain at less than 2 per cent of the total market for many years to come. It may be noted here that, global climate change may be best addressed in the short term by energy conservation, by increasing fuel efficiency, and by subsurface storage of the carbon dioxide that results from burning fossil fuels. At the same time, the greatest advantages of nuclear power is that it avoids the wide variety of environmental problems arising from burning fossil fuels, apart from economically generating a high amount of electrical energy in one single plant using small amount of fuel.

H. Therefore, concerted efforts by such economies, in order to have secured energy for their sustainable developments, should involve large scale nuclear expansion, the development of clean coal-fired power stations, implementation of hydro-electric power to maximum potential and a increase in renewable energy sources such as solar and wind.

Thursday, July 31, 2008

Glass recycling – An effective way to save energy and environment:

Glass recycling – An effective way to save energy and environment:

Generally, beer, wine bottles and other food jars etc., are among the few normal household glass items put into landfills every day. The glass in these items can take up space in the landfills for up to 4000 years.

A. The beauty of glass is, it is one of the few materials that can be recycled indefinitely, yet only about 22 percent of the glass produced today is from recycled materials. Glass is generally produced from sand, lime and soda and uses about 40 percent more power to produce from raw materials than it does with recycled materials.

B. It may be noted, “For every ton of glass that is recycled to make new glass products 693 pounds of carbon dioxide is saved”.

C. However, not all the glass items are recyclable. The glass in light bulbs, cook ware and window panes are not recyclable due to some special additives used to the glass. These additives are ceramics and other impurities that generally contaminate the recycling process. The glass that cannot be recycled only plays a small part of the glass that is put into the landfills though.

D. The process of glass recycling is less extensive than the process of making it from raw materials. Once glass is picked up and taken to the recycle center it is separated by color and then broken into small pieces. The broken glass pieces are then crushed and sorted before being cleaned and added to raw materials to make the final glass product. Crushed glass melts at a lower temperature than the raw materials and therefore the more recycled material that is in the mixture the less energy it takes to melt the materials into glass.

E. Producing glass from all raw materials creates nearly 400 pounds of mining waste and by replacing 50 percent of the raw material with recycled glass about 75 percent of that waste is reduced.

F. Reusing glass is another way to recycle - Even better than glass recycling is actually reusing the glass containers, as this uses no energy at all! Whilst returning bottles in exchange for a refundable deposit was at one time commonplace, nowadays milk bottles are one of the few types of glass bottle which are returned for reuse. You can, however, reuse glass bottles and jars yourself, perhaps for homemade jam etc.

G. The benefits of glass recycling are crystal clear - Because glass containers are almost always recycled into other glass containers. Metals or plastics, on the other hand, often become entirely different products. A recycled glass container is just as strong as one made from virgin material, and it can be recycled again and again without any loss of quality. This makes glass recycling one of the best examples of “closing the loop.”

H. Advantages of glass recycling are given in the following points–

(a) Recycling reduces the demand for raw materials. There is no shortage of the materials used, but they do have to be quarried from our landscape, so from this point of view, there are environmental advantages to recovering and recycling glass. For every tonne of recycled glass used, 1.2 tonnes of raw materials are preserved.

(b) The cost savings of recycling is in the use of energy. Compared to making glass from raw materials for the first time, cullet melts at a lower temperature. So we can save on energy needed to melt the glass.

(c) Glass produced from recycled glass reduces related air pollution by 20% and related water pollution by 50%.

(d) Recycling glass reduces the space in landfills that would otherwise be taken up by used bottles and jars.

(e) Using glass for recycling means there are less glass objects lying around in he landfill or bin.

Wednesday, July 30, 2008

Desert Solar Power – Future of environmentally clean and sustainable Energy:

Desert Solar Power – Future of environmentally clean and sustainable Energy:

A recent renewed interest in alternative energy technologies has revitalized interest in solar thermal technology, a type of solar power that uses the sun’s heat rather than its light to produce electricity. Although the technology for solar thermal has existed for more than two decades, projects have languished while fossil fuels remained cheap. But solar thermal’s time may now have come — and mirrored arrays of solar thermal power plants, hopefully, will soon bloom in many of the world’s deserts.

Large desert-based power plants concentrate the sun’s energy to produce high-temperature heat for industrial processes or to convert the solar energy into electricity. It is quite interesting to note that, as per the recent reports on Solar Power, the resource calculations show that just seven states in the U.S. Southwest can provide more than 7 million MW of solar generating capacity, i.e., roughly 10 times that of total electricity generating capacity of U.S. today from all sources.

In US, as per report, four more concentrating solar technologies are being developed. Till now, parabolic trough technology (i.e., tracking the sun with rows of mirrors that heat a fluid, which then produces steam to drive a turbine) used to provide the best performance at a minimum cost. With this technology, as per the report, since the mid-1980s nine plants, totaling about 354 MW, were operating reliably in California’s Mojave Desert. Natural gas and other fuels provide supplementary heating when the sun is inadequate, allowing solar power plants to generate electricity whenever it is needed. In addition, in order to extend the operating times of solar power plants new heat-storing technologies are being developed as well.

Realizing the advantages of solar energy and seeing the success of desert solar power installed, several solar power plants are now being planned in the U.S. Southwest. Renewed Governmental supports and rising fossil fuel prices including natural gas, lead to new interest in concentrating solar power among many entrepreneurs. Efficiency of concentrating solar technologies has also been improved substantially, since then. While earlier trough plants needed a 25 percent natural gas-fired backup, the new improved plants will require only about 2 percent backup. As per recent news in US, utilities in states with large solar resources such as Arizona, California, Nevada, and New Mexico etc., are considering installation of solar dish systems on a larger scale. As per the latest estimation, within the next decade more than 4,000 MW of central solar plants will be installed. It’s quite encouraging!!

Concentrating Solar Technologies -

(a) Parabolic trough technologies track the sun with rows of mirrors that heat a fluid. The fluid then produces steam to drive a turbine.

(b) Central receiver (tower) systems use large mirrors to direct the sun to a central tower, where fluid is heated to produce steam that drives a turbine. Parabolic trough and tower systems can provide large-scale, bulk power with heat storage (in the form of molten salt, or in hybrid systems that derive a small share of their power from natural gas).

(c) Dish systems consist of a reflecting parabolic dish mirror system that concentrates sunlight onto a small area, where a receiver is heated and drives a small thermal engine.

(d) Concentrating photovoltaic systems (CPV) use moving lenses or mirrors to track the sun and focus its light on high-efficiency silicon or multi-junction solar cells; they are potentially a lower-cost approach to utility-scale PV power. Dish and CPV systems are well suited for decentralized generation that is located close to the site of demand, or can be installed in large groups for central station power.

Conclusion – Now also the cost of solar power is quite high. In fact, for solar energy to achieve its potential, plant construction costs will have to be further reduced via technology improvements, economies of scale, and streamlined assembly techniques. Development of economic storage technologies can also lower costs significantly. According to renewable energy department, a solar plant covering 10 square miles of desert has potential to produce as much power as the Hoover Dam of US produces. Thus, desert-based power plants can provide a large share of the nation’s commercial energy needs.

Tuesday, July 29, 2008

Solar power – Energy that is most sustainable to protect our economy and environment:

Solar power – Energy that is most sustainable to protect our economy and environment:

Originally developed for energy requirement for orbiting earth satellite - Solar Power – have expanded in recent years for our domestic and industrial needs. Solar power is produced by collecting sunlight and converting it into electricity. This is done by using solar panels, which are large flat panels made up of many individual solar cells. It is most often used in remote locations, although it is becoming more popular in urban areas as well.

There is, indeed, enormous amount of advantages lies with use of solar power specially, in the context of environmental impact and self-reliance. However, a few disadvantages such as its initial cost and the effects of weather conditions, make us hesitant to proceed with full vigor. We discuss below the advantages and disadvantages of Solar Power:

Advantages -

(a) The major advantage of solar power is that no pollution is created in the process of generating electricity. Environmentally it the most Clean and Green energy. Solar Energy is clean, renewable (unlike gas, oil and coal) and sustainable, helping to protect our environment.

(b) Solar energy does not require any fuel.

(c) It does not pollute our air by releasing carbon dioxide, nitrogen oxide, sulfur dioxide or mercury into the atmosphere like many traditional forms of electrical generation does.

(d) Therefore Solar Energy does not contribute to global warming, acid rain or smog. It actively contributes to the decrease of harmful green house gas emissions.

(e) There is no on-going cost for the power it generates – as solar radiation is free everywhere. Once installed, there are no recurring costs.

(f) It can be flexibly applied to a variety of stationary or portable applications. Unlike most forms of electrical generation, the panels can be made small enough to fit pocket-size electronic devices, or sufficiently large to charge an automobile battery or supply electricity to entire buildings.

(g) It offers much more self-reliance than depending upon a power utility for all electricity.

(h) It is quite economical in long run. After the initial investment has been recovered, the energy from the sun is practically free. Solar Energy systems are virtually maintenance free and will last for decades.

(i) It's not affected by the supply and demand of fuel and is therefore not subjected to the ever-increasing price of fossil fuel.

(j) By not using any fuel, Solar Energy does not contribute to the cost and problems of the recovery and transportation of fuel or the storage of radioactive waste.

(k) It's generated where it is needed. Therefore, large scale transmission cost is minimized.

(l) Solar Energy can be utilized to offset utility-supplied energy consumption. It does not only reduce your electricity bill, but will also continue to supply your home/ business with electricity in the event of a power outage.

(m) A Solar Energy system can operate entirely independently, not requiring a connection to a power or gas grid at all. Systems can therefore be installed in remote locations, making it more practical and cost-effective than the supply of utility electricity to a new site.

(n) The use of solar energy indirectly reduces health costs.

(o) They operate silently, have no moving parts, do not release offensive smells and do not require you to add any fuel.

(p) More solar panels can easily be added in the future when your family's needs grow.

(q) Solar Energy supports local job and wealth creation, fuelling local economies.


(a) The initial cost is the main disadvantage of installing a solar energy system, largely because of the high cost of the semi-conducting materials used in building solar panels.

(b) The cost of solar energy is also high compared to non-renewable utility-supplied electricity. As energy shortages are becoming more common, solar energy is becoming more price-competitive.

(c) Solar panels require quite a large area for installation to achieve a good level of efficiency.

(d) The efficiency of the system also relies on the location of the sun, although this problem can be overcome with the installation of certain components.

(e) The production of solar energy is influenced by the presence of clouds or pollution in the air. Similarly, no solar energy will be produced during nighttime although a battery backup system and/or net metering will solve this problem.

(f) As far as solar powered cars go - their slower speed might not appeal to everyone caught up in today's fast track movement.

Conclusion - Solar power technology is improving consistently over time, as people begin to understand the benefits offered by this incredible technology. As our oil reserves decline, it is important for us to turn to alternative sources for energy. Therefore, it would be better that converting some of the world's energy requirements to solar power are in the best interest of the worldwide economy and the environment. Since we all are aware of the power of the sun and the benefits we could get from it.

Monday, July 28, 2008

Bio-degradable plastics – development and use are the key for improvement of environment:

Bio-degradable plastics – development and use are the key for improvement of environment:

A. At present, we make almost 100% of plastics of our requirement from oil and natural gas. Petroleum-based plastics are basically non-degradable. As concern grow about the potential bad effects of petroleum-based non-degradable plastics on the environment, the viability of petroleum-based plastics are in question. At the same time, the increased dependence on oil and gas imports due to manufacture of such petroleum-based products, make us think about the possible solution. In this respect, searching for suitable degradable polymers for various applications as per the need, have become very important aspect in today’s science and technological affair for research.

B. As per reports of various environment protection agencies, plastics alone account for more than 25% (by volume) of municipal waste generated. Plastic’s low density and slowness to decompose makes them a visible pollutant of public concern. Some of the techniques adopted for integrated waste management, which include recycling, source reduction of packaging materials, composting of degradable wastes, incineration etc., may help reduce waste disposal problem; but this will not solve the importation of petroleum products and problem with non-degradability of plastics. As per statistics, about 80% of post-consumer plastic waste is sent to landfill – degrading land masses and causing water pollution, 8% is incinerated – causing unwanted emission and only 7% is recycled. The situation is so acute in some countries of Europe of Japan that today few sites left that can be used for landfill. Since the main bulk of domestic waste is made up of plastics there is a great deal of interest in recycling plastics and in producing plastic materials that can be safely and easily disposed of in the environment.

C. The option to get rid of the adverse effects of non-degradable petroleum-based plastics may be to make bio-degradable plastics suitable for our various applications. Some of the manufacturers in developed countries have already developed some type of degradable plastics made from agricultural products such as corn, potato etc. In fact, bio-degradable plastics can be made from lactic acid. Lactic acid is produced (via starch fermentation) as a co-product of corn wet milling, which can be converted to polyactides (PLA). Alternatively, it can be produced using the starch from food wastes, cheese whey, fruit or grain sorghum.

D. The properties of the plastics changes as per the applications for which it is needed. Some plastics need to be durable like the parts in a car. Yet, there are many plastics that are only used once or have a limited life before being thrown into a landfill or incinerator. Plastics, unlike most organic polymers, are poorly degraded by microbes (although recently some genetically engineered microbes / bacteria have been invented to transform plastic waste into useful eco-friendly plastics – but it is still in research stage). Environmentally degradable polymers are one potential solution to replacing petroleum-based polymers. Potential uses for these polymers are plastics intended for one-time or limited use, for example those used as fast-food wrappers and water-soluble polymers in detergents and cleaners, and for use in the printing industry. Thus, an ideal degradable product would:

(a) Perform the intended task effectively;

(b) Produce little or no side effects in any non-intended target;

(c) Break down, along with any residues of its activity, over a reasonably short time scale;

(d) Produce no harmful substances when it breaks down.

E. Waste disposal: The question now arises, how best to dispose of domestic wastes. The ways of disposing of waste and time required for degradation is very important factors in development of bio-degradable plastics. Current bio-degradable polymers are designed to degrade either biologically or chemically, depending on the disposal environment that they will encounter after use. Ideally, degradation pathways should ultimately lead to the bio conversion of the polymer into carbon dioxide (aerobic) or carbon dioxide/methane (anaerobic) and biomass. Environmental laws and regulations and consumer demands for environmentally friendly products are beginning to have an impact on the use of degradable polymers. As a result degradable polymers, when combined with other degradable plastics, will begin playing a crucial role in helping to solve our waste disposal problems and reducing petroleum imports.

F. Properties of bio-degradable polymers: These new polymers developed from agricultural products described above are truly degradable. These polymers may be used in many applications as well. Some are impervious to water, moisture etc., and retain their integrity during normal use, but readily degrade when they are kept in a biologically rich environment. The amazing part is the full biodegradability can occur only when these materials are disposed of properly in a composting site or landfill. Today, there are three major degradable polymers groups that are either entering the market or are positioned to enter the market. They are

(a) polyactides (PLA),

(b) polyhydroxybutyrate (PHB) and

(c) starch-based polymers.

G. Design for Bio-Degradation of Polymer: Following few points are given to attain bio-degradability.
(a) Some organic chemicals degrade only very slowly, and so the level in the environment can rise steadily. These are the persistent organic pollutants (or "POPs").

(b) In contrast, all chemicals produced in nature are 100% degradable and understanding why this is the case is an important part of being able to design synthetic degradable materials.
(c) For example, natural polymers such as carbohydrates, proteins and nucleic acids usually have oxygen or nitrogen atoms in the polymer backbone. If these atoms are included in synthetic polymers, the material is more easily degraded. A carbon-oxygen double bond (carbonyl group) absorbs light energy, and so can make a substance photodegradable.
(d) These features can be seen in the structures of some degradable polymers that are already in use.

H. Bio-degradable polymers are quite new. Only during last five years some bio-degradable polymers for applications have been in use in some of the developed world. Although they are degradable, the industry has not promoted them. One reason is these new polymers are higher priced than the commodity polymers typically in use in plastics applications. However, producers are currently working toward bringing down the price of degradable polymers by increasing production capacity and improving process technology.

I. Price competitiveness and future growth of bio-degradable polymers: The trend observed regarding bringing down the prices of degradable polymers in last five years is quite encouraging. In US, five years ago PLA and PHB sold for more than USD 25.00 per pound. Today PLA, depending on quantities, is between USD 1.50 and USD 3.00 per pound and PHB, in large quantities is near USD 4.00 per pound.

Though recent advances in production technology have helped lower prices of some degradable resins, prices are still higher than for petroleum-based plastics. This suggests that in the short term, companies making degradable polymers will continue to focus on niche markets. As production capacity increases it is expected that future prices to fall to roughly USD 1 per pound. Moreover, due to sharp increase in prices of petroleum-based plastics in recent time, the prices of bio-degradable polymers will become very much competitive soon.

J. Further, several factors, besides cost, will be important in determining the future growth of degradable polymers. One major obstacle is a lack of a composting infrastructure. Large-scale composting would provide the ideal disposable environment for spent degradable. Future legislation will depend not only on the environmental awareness of planners and politicians but also on their perceptions of how degradable polymers may affect the development of plastics recycling.

Friday, July 25, 2008

R&D priorities in biotechnology are essential to take care of post-Kyoto challenges:

R&D priorities in biotechnology are essential to take care of post-Kyoto challenges:

A. Global Warming: The third session of the Conference of the Parties to the United Nations Framework Convention on Climate change, held in Kyoto, Japan, on December 1997, agreed on a protocol which includes each party’s quantitative commitment to reduce its emissions of greenhouse gases, such as carbon dioxide (CO2) by 2010. The protocol specifies that the European Union will commit itself to reducing its greenhouse gas emissions by 8 per cent by 2010 from the level of 1990 (base year), the United States by 7 per cent, and Japan and Canada by 6 per cent. As an essential element in achieving this goal, industry must reduce energy consumption in order to maintain development while helping to meet these targets.

This would include a shift from present petrochemical industry processes, which consume large quantities of energy under conditions of high temperature and pressure, to more energy-efficient biological processes, which use renewable resources such as biomass to produce useful substances under normal temperatures and pressures. For example, future processes will focus more on producing efficiently alternative fuels such as ethanol, which contribute less to global warming and are also likely to produce environmentally benign products, such as biodegradable plastics, which breaks down in natural settings after use.

As a result, biotechnology should become an increasingly valuable tool for developing environmentally friendly products and processes and for preventing the Earth from warming.

B. R&D priorities in biotechnology for promotion of clean industrial products and processes: If biotechnology is to become an increasingly important source of clean industrial products and processes, R&D efforts will need to focus on a number of priority areas. Among those that deserve prompt and focused research in the near future are:

a. Innovative products derived from biological sources that contribute to sustainability;

b. Wider exploration of biological systems (enzymes, micro-organisms, cells, whole organisms);

c. Greater emphasis on the use of bioconsortia, including establishing them and developing production and degradation processes based on them;

d. Novel methodologies for developing biological processes (bio-molecular design, genomics);

e. Innovative biocatalyst technology for use in areas where conventional biocatalysts have not yet been exploited (e.g. the petrochemical industries);

f. Biological recycling processes that convert unused resources to useful substances;

g. Emphasis on engineering, especially large-scale engineering, process intensification, measurement, monitoring and control systems;

h. Greater emphasis on biodiversity and widening the search for novel genes (bioprospecting), a process that will require, in parallel, the construction of infrastructures such as culture collections, comprehensive biological databases, and the development of bioinformatics;

i. Focus on development and application of recombinant technology.