Ozone recovering but will take longer over poles

Posted on September 17, 2010 by Rashid Faridi

The ozone layer that shields life from the sun’s harmful rays is projected to recover from harmful chemicals by mid-century, but it will take longer over the polar regions, a United Nations study said.

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Biomass as a Renewable Energy Resource

Posted on September 16, 2010 by Rashid Faridi

Biomass is a renewable energy resource derived from the carbonaceous waste of various human and natural activities. It is derived from numerous sources, including the by-products from the timber industry, agricultural crops, raw material from the forest, major parts of household waste and wood.

Biomass does not add carbon dioxide to the atmosphere as it absorbs the same amount of carbon in growing as it releases when consumed as a fuel. Its advantage is that it can be used to generate electricity with the same equipment or power plants that are now burning fossil fuels. Biomass is an important source of energy and the most important fuel worldwide after coal, oil and natural gas.

Traditional use of biomass is more than its use in modern application. In the developed world biomass is again becoming important for applications such as combined heat and power generation. In addition, biomass energy is gaining significance as a source of clean heat for domestic heating and community heating applications. In fact in countries like Finland, USA and Sweden the per capita biomass energy used is higher than it is in India, China or in Asia.

Biomass fuels used in India account for about one third of the total fuel used in the country, being the most important fuel used in over 90% of the rural households and about 15% of the urban households.

Instead of burning the loose biomass fuel directly, it is more practical to compress it into briquettes (compressing them through a process to form blocks of different shapes) and thereby improve its utility and convenience of use. Such biomass in the dense briquetted form can either be used directly as fuel instead of coal in the traditional chulhas and furnaces or in the gasifier. Gasifier converts solid fuel into a more convenient-to-use gaseous form of fuel called producer gas.

Scientists are trying to explore the advantages of biomass energy as an alternative energy source as it is renewable and free from net CO2 (carbon dioxide) emissions, and is abundantly available on earth in the form of agricultural residue, city garbage, cattle dung, firewood, etc. Bio-energy, in the form of biogas, which is derived from biomass, is expected to become one of the key energy resources for global sustainable development.

At present, biogas technology provides an alternative source of energy in rural India for cooking. It is particularly useful for village households that have their own cattle. Through a simple process cattle dung is used to produce a gas, which serves as fuel for cooking. The residual dung is used as manure.

Biogas plants have been set up in many areas and are becoming very popular. Using local resources, namely cattle waste and other organic wastes, energy and manure are derived. A mini biogas digester has recently been designed and developed, and is being in-field tested for domestic lighting.

Indian sugar mills are rapidly turning to bagasse, the leftover of cane after it is crushed and its juice extracted, to generate electricity. This is mainly being done to clean up the environment, cut down power costs and earn additional revenue. According to current estimates, about 3500 MW of power can be generated from bagasse in the existing 430 sugar mills in the country. Around 270 MW of power has already been commissioned and more is under construction.

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6 Ways to Burn a Hole in the Ozone

Posted on September 15, 2010 by Rashid Faridi

Guest post by Ron Delfs

Ozone depletion is a very real and very frightening reality on planet Earth. The ozone layer is a protective shield in the stratosphere that protects us from the sun’s harmful ultraviolet rays. During the 1980s, scientists noticed that the ozone was decreasing in Earth’s polar regions. It was later discovered that chlorofluorocarbons (CFCs), a popular compound that was used in various products like refrigerants, air-conditioning and cleaning agents, was a major cause in ozone depletion. With every spray of aerosol hairspray and flow of air conditioning, CFCs were emitted into the atmosphere, carried by winds up to the stratosphere and broken down by UV radiation, releasing chlorine atoms that destroyed the ozone layer. Since this discovery, the U.S. and other countries agreed to the Montreal Protocol treaty that has regulated the manufacturing, sale and use of CFCs and it’s alternative, HCFCs. Through collective efforts of developed countries, there has been a significant reduction in ozone depletion, but CFCs and HCFCs are still being used commercially and by developing countries. For your reference, here are 6 ways to burn a hole in the ozone:
Use Inhalers
A metered dose inhaler (MDI) is a hand-held, pressurized tool used to deliver small doses of medication to the lungs for patients with asthma and chronic obstructive pulmonary disease (COPD). For every puff of an inhaler, the more CFCs are being emitted into the atmosphere and depleting the ozone layer because MDIs are still made with these compounds. Research is underway to implement alternatives for CFCs in inhalers, but is not available yet.
Use Document Preservation Sprays
Document preservation sprays will certainly burn a hole in the ozone layer because they still contain CFCs or HCFCs as propellants. In order to regulate the emissions, document preservation sprays may only be used on thick books, books with coated or dense paper and tightly bound documents.
Use a Fire Extinguisher
If there’s a fire in your office kitchen, school laboratory or local restaurant, a portable fire extinguisher is most often used to put out the fire. What you may not know is that non-residential fire extinguishing equipment, like a portable fire extinguisher, still contains HCFCs that burn a hole in the ozone. However, these extinguishers may be used in non-residential applications only.
Use Aerosol Hairsprays
While the use of CFCs in aerosol hairsprays has been phased out in developed countries, it is still used in developing countries that have not implemented an alternative compound for aerosols. Today’s aerosol hairsprays contain HFCs, which are thought to be more ozone-friendly, but certainly contribute to global warming.
Use Wasp and Hornet Sprays
Using wasp and hornet killer sprays is a guaranteed way to burn a hole in the ozone because these aerosol products contain HCFCs to replace CFCs. According to the EPA, wasp and hornet sprays can only be used near high-tension power lines, and the seller must notify customers about these restrictions.
Use Foam Insulation Products
Foam insulation products are used for appliance, residential and commercial insulation applications, such as refrigerated storage and transport or pipe insulation. Foam insulation products are still made with HCFC blowing agents because its HFC alternative has not been implemented across all nations.

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Bhakra ’tilt’ raises flood fears in India

Posted on September 15, 2010 by Rashid Faridi

With deflection — in layman’s parlance ’tilt’ — confirmed in the structure of the iconic Bhakra dam beyond permissible limit, serious concerns for the safety of the dam are being raised. The possibility of a repeat of the 1988 “man-made” floods in Punjab is being discussed, impelling environmental experts to demand an independent inspection of the dam.

While the Bhakra-Beas Management Board (BBMB) on Monday gave an assurance that there was no threat to the dam, a concerned PMO has sought a report from the BBMB authorities. The latter have admitted that the level of deflection is 1.05 inches, which is above the permissible level of 1.03 inches. “It’s cause for concern if the deflection has gone beyond permissible limits,” said Pune-based Shripad Dharmadhikary.

This came a day after the dam was allowed to be filled above the full reservoir level (FRL) of 1680 ft limit. According to the norms maintained by the BBMB earlier, water beyond this limit is supposed to be released out of the reservoir to avoid any sharp deflection which could damage the dam, and to maintain cushion for storing more water in case of heavy rainfall upstream.

Denying possibility of any damage to the dam structure, BBMB official M K Gupta said, “There’ve been instances when the deflection went up to 1.07 inches in the past, without posing any threat to the dam’s safety. As long as there’s no seepage in the dam gallery, there is no cause for worry.”

“If, God forbid, the dam’s structure is damaged, it can result in a huge tragedy since most parts of Punjab would get wiped out by the waves,” said G S Dhillon, associated with the designing of Bhakra dam in the early 1950s.

Deflection has been recorded earlier during this filling season as well. Continuous rainfall over the past two days has increased the worries as the FRL in Bhakra dam was recorded at 1680.37 ft on Monday, and the inflow was 63,000 cusecs as against the outflow of 38,000 cusecs of water.

In 1988, Punjab saw widespread floods and immense damage when BBMB opened the sluice gates and released 1.45 lakh cusecs of water.
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