ᗩmnᗩ's Blog

Once a group of 500 people were attending a seminar. Suddenly the speaker stopped and decided to do a group activity. He started giving each person a balloon. Each person was then asked to write their name on it using a marker pen. Then all the balloons were collected and put in another room.

The people were then let into that room and asked to find the balloon which had their name written on it within 5 minutes. Everyone was frantically searching for their name, colliding with each other, pushing around others and there was utter chaos.

At the end of 5 minutes no one could find their own balloon.
Then, the speaker asked each person to randomly collect a balloon and give it to the person whose name was written on it. Within minutes everyone had their own balloon.

The speaker then began, “This is happening in our lives. Everyone…

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FOR FUTURE GENERATIONS – Assessing the Hybrid Power Potential

The WWF has recently published a Report (Feb 2014) funded by WWF and Chinese Government with the title “China’s Future Generations – Assessing the Maximum Potential for Renewable Power Sources in China to 2050”. The report is available online for the benefit of concerned who care for a future dominated by clean and efficient energy usage.

This excellent report provides an analysis, based on modelling of Chinese existing Power Grid and assuming certain future forecasts, whereby it has been highlighted that environment can be improved and renewable energy can become a major part of Chinese power source. The study does not recommend 100 percent dependence on renewables as the only source of energy. In essence, it recommends Hybrid power supply systems as a mix of wind, solar, hydel and gas. The study is very informative and provides guidelines for Chinese government to improve their energy mix and environment. Other nations can also benefit from the methodology described therein and built their own models related to their energy supply mix. Not to say the least, the study demonstrates that China can reduce its power consumption to almost 50% of the future projections through energy efficiency measures. Its time that we should all put maximum emphasis on energy efficiency be it lighting, household equipment, business equipment, transport or recreation. The report is available here ………… HAPPY READING.

FOR 2014 – THE MOST FASCINATING GREEN ACT

We all know, especially the Qataris, that Brazil will be hosting the 2014 FIFA World Cup. Brazilians have undoubtedly been doing a great job to make this world’s premier sporting event as environment friendly as possible. From among the various Green Buildings commissioned in 2013, Brazil’s Castelao Arena Football stadium is the most fascinating, especially for sports lovers.

Recently completed in Fortaleza city of north-eastern Brazil, as the first of the 12 venues to be completed, Castelao Arena became the first World Cup stadium to earn LEED certification in November 2013. It is expected that during 2014 FIFA World Cup over 60,000 fans will be witnessing every match along with enjoying and praising the sustainable features of this LEED certified stadium. As reported byUSGBC (United States Green Building Council), some of the key features of this stadium are listed here:

1. Water Use: Stadium design accommodates a 67.6% reduction in potable water consumption, and a 71.9% reduction in the volume of potable water directed to the local sewer system.
2. Energy Consumption: Through smart-building optimization, the stadium will reduce annual energy consumption by 12.7%. An ongoing information-sharing tool works to maintain this level of efficiency in years ahead.
3. Construction Waste Reduction: During the stadium’s construction, 97% of all waste was diverted from landfills and reused or recycled.
4. Event Waste Reduction: Strategically positioned central waste disposal units are set to store and recycle event waste, including paper, cardboard, plastic, glass and metal.
5. Indoor Environmental Quality:

• • A monitoring system ensures the continuous thermal comfort of guests.
  • Low VOC materials were used throughout, and 100% of sealants, paints and coatings used internally comply with acceptable limits.
  • Lighting design enables 97% of all individual workstations and 100% of all shared spaces to be individually controlled.

Brazilians have indeed done a significant effort in making FIFA 2014 World Cup an event which shall promote sustainable environment concept and showcase it to all the sports lovers during the New Year 2014.

 

HAPPY GREEN 2014 to everyone ……… especially to Brazilians.

Solid Waste Management – Everybody’s Contribution Solicited

Waste Management is defined as its collection, transportation, processing and / or disposal with additional function of monitoring waste materials impact on environment, human health and aesthetics. Waste materials can be solid, liquid, gaseous or radioactive and waste management encompasses all of these. Out of these, Solid Waste Management ( SWM ) can be considered as an activity which can be participated by all sectors of society for affective implementation. This is true for developed as well as developing nations, for urban as well as rural areas and for residential as well as industrial producers. Although major responsibility of facilitating and monitoring SWM lies with local government authorities, the generators of this waste can significantly contribute to the success of such a program by implementing the required waste disposal practices.

Various methods are used for SWM as summarily described in following text.

INCINERATION (Waste-to-Energy) – Incineration is the process to generate green energy through Waste-to-Energy (WTE) technologies. There are various WTE technologies available like Gasification & Pyrolysis, Mass Burn and Refused-Derived Fuel (RDF). Gasification and Pyrolysis systems employ thermal processes to extract  synthetic gas or vapor from waste by using heat in an atmosphere of deficient oxygen, such synthetic gas in turn is used as burning fuel. Mass Burn is a process whereby raw or post-recycled waste is fed into a furnace for supplementing normal fuel and thus creating extra energy for electricity generation. RDF systems convert recycled waste into solid fuel that is sold for commercial use or further processed through gasification & Pyrolysis or mass burn. The workings of these technologies differ but the underlying objective is the same – economically extracting renewable energy from left-over waste.

METAL RECYCLING (Resource Recovery) – Metal recycling is a major contributor to economy as well as environment. Through metal recycling, societies enable themselves to reuse metals that were otherwise difficult or uneconomical to obtain. Metal recycling involve Sorting, Shredding, Media Separation, Shearing, Melting and Baling (compacting steel products into large steel blocks to facilitate handling). Millions of Tons of ferrous as well as non-ferrous scrap is recycled every year to extract useful metals. The most commonly used non-ferrous metals are aluminium, copper, lead, zinc, nickel, titanium, cobalt, chromium and precious metals. Due to limited availability of some non-ferrous metals, recycling and flow of non-ferrous scrap from country to country according to industrial and consumer demand is crucial in today’s world.

ELECTRICAL & ELECTRONICS EQUIPMENT RECYCLING (Advanced Resource Recovery) – Electronics and electrical equipment waste is usually around 105 of the current solid waste stream, it is growing at the fastest rate as compared to any other solid waste. Such waste refers to electronic and electrical products that have finished their useful life for consumer. Such waste contains special metals including rare earth metals and precious metals which are recoverable through specialized recycling processes. These advanced metal extraction processes are very important in recovery of metals which are scarcely available in nature. Due to complex functionality, today’s electronic products contain complex compounds of metals, thus making it difficult to extract and reuse valuable metals from waste products due to laws of physics and related economics. To take an example, a mobile phone contain more than 40 elements, including base metals such as copper and tin and precious and platinum-group metals like silver, gold and palladium. Today the concentration of metal recyclers should be more on Product-Centric recycling wherein they should target specific metals recovery from End of Life (EoL) products.

BIOLOGICAL REPROCESSING (Composting) – Composting is very important to recycle food waste because food waste (and other organic materials). When such waste end up in garbage these do not decompose properly creating methane (a powerful greenhouse gas) and we lose the chance to recover resources by turning food scraps into energy or compost. Composting is a mixture of various decaying organic substances like food waste, dead leaves and manure that is used for fertilizing soil. Households and Offices can use backyard composting of worm bin composters to compost organic waste produced by them in most efficient manner. Most local governments are drafting laws to ban disposal of food waste and compostable organics in regular waste. Special incentives are also being arranged for onsite composting or to process such organic waste separate from other waste material.

HAZARDOUS WASTE MANAGEMENT (Small evil Big problem) – Hazardous waste like asbestos, lead acid batteries, automobile parts, fluorescent lights, gypsum, biomedical waste, pesticide products, containers of poisonous chemicals, thermostats, tires, waste containing polycyclic aromatic hydrocarbons and banned recycled plastic are some examples of hazardous waste that should not be mixed with regular waste material. Hazardous waste contains toxic chemicals and heavy metals which are harmful to environment as well as waste disposal staff, and should be managed through special waste treatment programs including recycling, treatment, abandonment, storage and disposal. Information regarding such waste disposal should be made available by local governments to the general public for ease of implementation.

WASTE MINIMIZATION (Sustainability) – Most of the problems related to solid waste management can be minimized through minimizing the waste produced by societies. We can reduce waste by considering the following:

• Intelligent selection of things that we use like selecting rechargeable batteries in place of simple batteries.
• Reconsider what we throw away – consider reuse.
• Inculcate food consumption habits that discourage food wastage.
• Reduce garbage at work.
• Local governments can encourage support for minimizing solid waste production through advocating reuse initiatives and starting a Zero Waste Community Challenge.
• Local governments should also create online databases allowing public awareness and interest in recycling of waste. Bureau of International Recycling provides information about benefits of recycling and currently provides following information for boosting interest in recycling:

1. CO2 emissions are reduced by 58% through the use of ferrous scrap.
2. An average stainless steel object is composed of about 60% recycled material.
3. Almost 40% of world’s requirements of copper are met by recycling.
4. Of all collected textile, 50% are reused and 50% are recycled.
5. Recycling paper saves 65% of the energy used to produce new paper.
6. Recycling a single plastic bottle can conserve energy to light 60-watt bulb for six hours
7. Scrap tyres used as fuel can produce same amount of energy as oil and 25% more than coal.

Unearth The Buried Technology – Geo Pressured Geothermal Resources

During mid-1970s the US Department of Energy (DOE) established a geopressured-geothermal energy program in line with development of alternative energy resources. This was done in view of America’s increasing dependence on imported fossil fuel energy which was highlighted in the early 1970’s as manifested through long lines at gas stations and limited amounts of fuel that could be purchased. As taken directly from the document by Chacko and others (1998), the goals of this program were “to define the extent of the geopressured reservoirs, determine the technical feasibility of reservoir development including downhole, surface and disposal technologies, establish the economics of production, identify and mitigate adverse environmental impacts, identify and resolve legal and institutional barriers and determine the viability of commercial exploitation of this resource.

Extensive work was carried out and numerous wells were investigated for various reservoir and resource potential, including those wells that various oil and gas companies made available for testing. The original concept as defined in the DOE document was to tap into three forms of energy within the region: the heat brought to the surface in the produced hot water (thermal energy); burning any entrained natural gas on site for electricity production (chemical energy); and using the high brine flow rates (>20,000 bbl/day) and the high well head pressure (mechanical energy) to generate electricity.

As a result, a hybrid  geopressured geothermal power plant in the U.S., Pleasant Bayou in Brazoria County, Texas, generated electricity from the geo-fluid and separated the natural gas to test the production of electricity from combustion in an on-site hybrid power system. The binary power plant with a design output of 905 KW (541 KW from ORC turbine, 650 KW from gas engine and subtracting an operational load of 286 KW) was operated between September 1989 and May 1990. The plant operated at only 10,000 bbl of water per day with small volumes of gas flow. Bottom hole temperature was given as 154 degree C, with a maximum brine T of 136 degree C. Permeability was estimated at around 160 md with a reservoir area of 36,000 acres. The overall plant availability was 97.5%, at par with many other geothermal plants. During the 121 days of operation, 3,445 MWh of electricity were sold to Houston Power and Light. The project was described as a success in the final report (Campbell and Hattar, 1991).

There could be various reasons in 1990s for not commercializing the project. But today, the energy industry, especially Oil and Gas companies cannot ignore such potential source of green energy. There are many abandoned / non-producing wells available in the assets of Oil & Gas companies which can be investigated for potential geothermal power plant sites.

References

Chacko, J.J., G. Maciasz, and B.J. Harder, 1998, Gulf coast geopressured-geothermal program summary report compilation: Volumes I, II A, II B, III, and IV: Basin Research Institute, Louisiana State University, DOE contract DE-FG07-95ID13366.

Campbell, R.G., and M.M. Hatter, 1991, Design and operation of a geopressured-geothermal hybrid cycle power plant: Final report vol. I, 180 p. and vol. II, 172; Eaton Operating Company, Inc. and United States Department of Energy, The Ben Holt Co., DOE contract DE-ACO7-85ID12578.

Geothermal-CSP Hybrid Plants – The Winning Combination For Electricity Generation

GEOTHERMAL PLANTS

There are currently many geothermal power plants operating in the world with an installed capacity of around 10,000 MW of electricity generation more significantly in USA, Philippines, Indonesia, Italy, Mexico, Iceland and Japan. These power plants are using different techniques to produce electricity from geothermal energy including the following:

• DRY STEAM POWER PLANTS: Super heated steam is drawn directly from under the earth’s surface by a turbine which drives the generator. The condensed water is re-injected into the geothermal reservoir.
• FLASH STEAM POWER PLANTS: These power plants draw geothermal water around 150 degree Centigrade under extremely high pressure from the underground reservoir. At the surface, throttling causes the heated water to vaporize or “flash” into super heated steam which is fed to the turbine for driving the generator. The condensed water is re-injected into the geothermal reservoir.
• BINARY CYCLE POWER PLANTS: These power plants operate with lower geothermal water temperatures around 100 degrees Centigrade. The ground water is not directly used to drive the turbine rather the hydrothermal resource is used to vaporize “Organic Fluid” having a lower boiling point than water. The organic fluid runs an Organic Rankine Cycle turbine which drives a generator, the cycle being a closed loop system. The extracted geothermal water is re-injected into the reservoir in a separate closed loop.

 

CSP PLANTS

The current installed capacity of concentrating solar thermal power (CSP) plants in the world is more than 2,550 MW. Spain leads the world for both deployment and total capacity of CSP with an operating capacity of 1,950 MW. The United States has the second largest capacity, around 500 MW in operation. Several North African countries, Chile, Australia, Thailand, China, France, Germany, India, Israel, Italy, and South Korea had small CSP plants in operation. A recent entry is United Arab Emirates (UAE) in March 2013, when Shams 1 (100 MW)—the first full-size pure CSP plant in the Middle East and North Africa (MENA) region—began operation. There is a growing interest in CSP, particularly in developing countries, with investment spreading across Africa, the Middle East, Asia, and Latin America. One of the most active markets in 2012 was South Africa, where construction began on a 50 MW solar power tower and a 100 MW trough plant.

 

GEOTHERMAL – CSP HYBRID PLANTS

It is being emphasized by various feasibility studies and demonstrated operations at running geothermal power plant sites that the electricity generation shall soon have geothermal-CSP HYBRID power plants as the major contributors. Currently such Hybrid systems are predominantly operating in USA like Oregon Demonstration Plant, Utah Power Plant and NREL project. US Department of Energy is providing financial support for these operations and the outcome is very encouraging. The major benefits that are currently being investigated as achievable by these Geothermal-CSP hybrid systems are:

• These Hybrid plants reduce risk because CSP can offset lack of initial geothermal resource productivity. Further by correctly optimizing the date and size of CSP array installation the NPV of the project can be improved. This implies that CSP could lower generation costs if it reduces risk & financing costs.
• CSP can bring geothermal plant output and conversion efficiency to design levels and above. CSP impact on plant output increases as production fluid temperature decreases from design value.
• Flexibility of evaluating Cost and performance of CSP vs. drilling of makeup wells over the life of geothermal plant.
• CSP can improve NPV when PPA (Power Purchase Agreement) penalties might be imposed. The hybrid plant can improve project NPV when used to avoid penalties associated with low power output caused by decreased geothermal resource productivity. Time of day pricing scenarios can produce more favorable hybrid plant economics as the CSP would enhance output of geothermal power plant at peak afternoon load.

Geothermal Heat pumps – The Choice Is Yours

The technology of the day has made it possible that your home, office building, factory or farm land – the place of your choice – can become source of your geothermal energy for Heating and Cooling (H&C). This was not true about geothermal energy few decades earlier. Geothermal energy comes from the hot inner core of Earth which exists because of the original formation of the planet and because of radioactive decay of minerals. Since long there have been Hot Springs used for bathing and the oldest known spa is a stone pool on China’s Lisan mountain built in the 3rd century BC. The world’s oldest geothermal district heating system in Claudes-Aigues, France, has been operating since the 14th century.

Geothermal power has historically been limited to areas near tectonic plate boundaries. But recent technological advances have dramatically expanded the range and size of viable resources, especially for applications such as space heating or cooling. The more demanding applications receive the greatest benefit from a high natural heat flux, ideally from using a hot spring. The next best option is to drill a well into a hot aquifer. If no adequate aquifer is available, an artificial one may be built by injecting water to hydraulically crack or fracture the bedrock. This last approach is called Hot Dry Rock Geothermal Energy or Enhanced Geothermal Systems (EGS). Much greater potential may be available from this approach than from conventional tapping of natural aquifers.

Today, geothermal energy is a clean, renewable resource that provides energy around the world in a variety of applications and resources. Geothermal energy is being used for electricity production, for commercial, industrial, and residential direct heating purposes, and for efficient home heating and cooling through geothermal heat pumps.

• Geothermal Electricity is developed from geothermal resources by drilling of wells into a geothermal reservoir. The wells bring the geothermal water to the surface, where its heat energy is converted into electricity at a geothermal power plant.
• Geothermal Heating is a direct use of earth’s heat, without involving a power plant or a heat pump, for a variety of applications such as space heating and cooling, food preparation, hot spring bathing, agriculture, aquaculture, greenhouses, and industrial processes.
• Geothermal Heat Pumps (GHPs): Geothermal heat pumps take advantage of the Earth’s relatively constant temperature at depths of about 10 ft to 300 ft. GHPs can be used almost everywhere in the world, as they do not share the requirements of fractured rock and water as are needed for a conventional geothermal reservoir. GHPs circulate water or other liquids through pipes buried in a continuous loop, either horizontally or vertically, under a landscaped area, parking lot, or any number of areas around the building. The Environmental Protection Agencies consider them to be one of the most efficient heating and cooling systems available. GHPs reduce electricity use by 30–60% compared with traditional heating and cooling systems, because the electricity which powers them is used only to collect, concentrate, and deliver heat, not to produce it.

Geothermal heating and cooling is currently applied in three different ways:

1. The first one (low temperature up to 30°C) is based on the relatively stable groundwater and ground temperatures at shallow depths (up to 500 m) – and therefore also near structural elements of buildings. Typically, heat pumps are used to extract energy from the ground and raise (and amplify) the energy to the temperature (and thermal efficiency/capacity) level required by the heating systems for the thermal conditioning of spaces and processes. The ground or groundwater can also be used for cooling, whereby at the right conditions the temperature can be applied directly. Furthermore the heat pump installation can also be used to provide cooling to the building or process, again providing the required temperature and amplifying the thermal capacity of the source. In certain conditions and configurations, the geothermal system can be used to (to control and optimise) ground temperatures artificially, in order to be used as heat or cold storage – UTES (Underground Thermal Energy Storage).
2. The second one extracts the heat from ground and groundwater at higher depths and temperature around 150°C. Direct applications are found in agriculture (horticulture, drying, fish-breeding), industrial processes, and balneology. It may also be applied to supply energy to a district heating or a combined heat and power installation or to drive local absorption heat pumps to provide cooling to the grid. District heating (and cooling) may also be supplied from residual heat left over after the production of electricity from a high enthalpy geothermal heat source.
3. Low to medium temperature applications can also make use of available surplus heat/cold from building heating/cooling application or from integration with solar thermal.

 

GEOTHERMAL HEATPUMPS

 

Unlike the other renewable energy sectors, geothermal heat pump industry is currently the most dynamic one. Low enthalpy ground source (the shallow systems) have been experiencing a rapid growth without the requirement of structural subsidies (governmental support).

There are different types of GHP heating and cooling applications:

1. Closed loop applications (vertical boreholes)
2. Closed loop applications (horizontal, shallow excavated systems)
3. Closed loop applications (foundation integrated systems)
4. Direct expansion
5. Groundwater applications (well based systems)

The current industry standard geothermal heat pump installations use vertical closed loop borehole collectors. A small number, mostly small residential applications use horizontal collectors.

 

 

DIRECT USES OF GEOTHERMAL HEATPUMP

 

There is no principle geographical restriction for the production of geothermal energy, geothermal heating and cooling supply can match the H&C demand anywhere because the resource is available everywhere. At present, geothermal energy is being used for district heating, as well as for heating (and cooling) of individual buildings, including both small (5-50 kW installed heat pump capacity), medium (50-500 kW) and large schemes (capacities > 1 MW) (offices, shops, health care, residential houses, schools, university buildings, commercial buildings, greenhouses, bathing etc. ).

Existing housing infrastructure represents an overwhelming share of the low temperature energy demand that can be logically supplied by geothermal district heating systems. Current benchmark studies indicate that direct use geothermal energy and district heating grids are probably the most effective option for this market, both in terms of carbon footprint and economics. However these developments are intrinsically fairly complex; necessitating the replacement of existing fossil energy based infrastructures which therefore require longer development times.

 

 

KEY CHALLENGES

The key challenge for the widespread direct use of geothermal heat will be the ability to reliably design, engineer and control geothermal heat pump installations, in order to be able to use the all-round potential of geothermal heat pump systems for sustainable energy efficiency. Intelligent planning with follow-up actions and cost reductions will allow the evolution of the current ‘hunter-gatherer’ economy of geothermal energy to a systematic and organized exploitation of geothermal resources.

The share of Shallow Geothermal Energy in our daily life can be increased by taking following steps:

Integration of geothermal energy in standard housing energy systems. Such a step necessitates the increased penetration of geothermal heat pumps into the market for new residential and commercial buildings. This advancement is dependent on Renewable Energy Systems (RES) becoming standard in new energy efficient buildings in all countries.

Develop Heating & Cooling networks integrating geothermal heat pumps and geothermal storage (UTES).Such a development would mean widespread Heating & Cooling networks based on geothermal energy in a time frame, followed by a constant part of the market of tertiary building and small Heating & Cooling networks. This would be based upon the rapid diffusion of Heating & Cooling networks, which have to become standard in urban planning.

Develop geothermal solutions for retrofitting of existing infrastructure. This advancement is based upon a number of critical factors. Firstly, products and methodologies for cost effective building energy refurbishment must be developed. Secondly, there must be a higher performance of high temperature heat pumps, or adoption of the buildings to low temperature space heating. Finally, the importance of improved energy efficiency standards, as part of renovation activities, is to be stressed in buildings regulation.

 

COSTS INVOLVED

To provide the readers with a feel of costs involved, a summary is tabulated below which is sourced from European Geothermal Energy Council.

Heating and Cooling	Average rates in European Markets$-cent/kWh
Deep Geothermal – District Heating	7
Geothermal Heat Pumps – large systems and UTES	8
Geothermal Heat Pumps – small systems	13

European Continent is very active in development of residential geothermal heat pumps. Geothermal Heat pumps with a capacity of 10 kW are routinely installed at a cost of around USD 3000 – 4000 per kW for closed loop systems. When the capacity is over 100 kW (large residential and tertiary buildings, schools, museums), open loop systems cost range is USD 700 – 1000 per kW. UTES systems for commercial and institutional buildings as well as for district heating and cooling have a capital cost of USD 130,000-190,000 per MWth (10% of the investment cost) referring to Swedish and Dutch experiences with a running cost of USD 30-40 per MWh.

STORAGE BATTERIES – THE LIFE LINE OF MODERN LIFE

Nobody could have imagined that an Electric Battery, consisting of electrochemical cells that convert stored chemical energy into electrical energy, shall ever assume a status of CRITICAL COMPONENT DEVICE of almost every operating equipment and system in today’s business, industries and households on this planet. These devices are manufactured today in the range from sizes smaller than a pencil eraser to as large as 2,000 square meters (21,528 square feet which is larger than a Football pitch). The largest battery in the world, capable of supplying 40 megawatts, was put in operation in August 2003 to power the entire town of Fairbanks, Alaska, a city of about 12,000 people, for up to seven minutes in an emergency situation [Source: Conway].

For the last decade or so, Batteries have received significant research and development, because they are an essential part in providing solutions for energy storage in a transition from fossil fuels to alternative energy, both for transport and electricity production. Rechargeable Batteries have been improved and developed on the core competencies in the fields of chemistry, material science and metallurgy. Billions of batteries are also used in powering devices as diverse as automobiles to mobile phones. Today the world battery sales, for primary (single use or disposable) and secondary (rechargeable) batteries, have crossed the USD 50 billion per annum mark and is growing at a fast pace. It is time that we should improve our knowledge and understanding about batteries so that we can make the best out of their usage.

HISTORY

In 1800, Italian physicist Alessandro Volta created the first electric battery, known as voltaic pile, capable of providing a continuous and controllable current of electricity. The voltaic pile was made of up of zinc and copper plates with vinegar- or brine-dampened pieces of pasteboard placed in between each plate. The plates were then stacked in alternating order, one plate acting as the positive terminal and the other as negative terminal. A year after Volta first introduced his voltaic pile he presented his invention to the French National Institute, in which Napoleon Bonaparte was in attendance. In honor of Volta’s invention, his name has since been used as the unit of electromotive measurement known as a VOLT.

Although voltaic piles were of great value for experimental purposes, their voltages fluctuated and they could not provide significant current for a sustained period. TheDaniell cell was invented in 1836 by John Frederic Daniell, a British chemist and meteorologist, and consisted of a copper pot filled with a copper sulfate solution, in which was immersed an unglazed earthware container filled with sulfuric acid and a zinc electrode. He was searching for a way to eliminate the hydrogen bubble problem found in the voltaic pile, and his solution was to use a second electrolyte to consume the hydrogen produced by the first. The Daniell cell was a great improvement in the technology used in the early days of battery development.

Starting with the Daniell cell in 1836, batteries were adopted by industry for use in stationary devices, in particular in telegraph networks where they were the only practical source of electricity. These wet cells used liquid electrolytes, which were prone to leakage. Many used glass jars to hold their components, which made them fragile. These characteristics made wet cells unsuitable for portable appliances. Near the end of the nineteenth century, the invention of dry cell batteries, which replaced the liquid electrolyte with a paste, made portable electrical devices practical.

RECHARGEABLE BATTERY TYPES

The most important in today’s large power supply systems, portable as well as stationary, are the Secondary Batteries or commonly known as Rechargeable Batteries. Rechargeable batteries have undergone tremendous development in recent years, and various types are commercially available. According to EPTA, the 3 main rechargeable battery chemistries currently in use are Li-Ion, NiCd and NiMH. Li-Ion is rapidly becoming the lead chemistry.

Lead Acid— One of the first rechargeable battery systems; they are economical in price; have low specific energy and limited cycle life. Lead acid batteries are commonly used for wheelchairs, golf cars, personnel carriers, emergency lighting and uninterruptible power supply (UPS). Their specific energy is around 50 Wh/kg, cycle life is 200-300 at 80% depth of discharge. Charging time is 8-16 hours with high overcharge tolerance. They are capable of high current pulses (5 times rated) but need time to recuperate.

Nickel-cadmium(NiCd) — A well developed technology which is used for long service life, high discharge current, extreme temperatures at economical price. These batteries are considered an environment hazards and as such NiCd is being replaced with other chemistries. Their specific energy is around 80 Wh/kg, cycle life is 1000 at 80% depth of discharge. Charging time is one hour which is the fastest with moderate overcharge tolerance. They are capable of high current pulses (20 times rated).

Nickel-metal-hydride(NiMH) — A practical replacement for NiCd; has higher specific energy with fewer toxic metals. These batteries are used for medical instruments, hybrid cars and industrial applications. Their specific energy is around 100 Wh/kg, cycle life is 500 at 80% depth of discharge. Charging time is 2-4 hours with low overcharge tolerance. They are capable of high current pulses (5 times rated).

Lithium-ion(Li‑ion) — This is the most promising battery technology which is used for portable consumer products as well as electric power trains for vehicles; these batteries are most expensive and they also need protection circuit for safety. Depending on the chemistry used, their specific energy is around 100-190 Wh/kg and cycle life is 500 up to 2000 at 80% depth of discharge. Charging time is 1-2 hours (less than one hour in some cases) with low overcharge tolerance (cannot tolerate trickle charge). They are capable of very high current pulses (as high as 30 times rated).

The lithium-ion family is further divided into various battery types based on different cathode oxides.

• Lithium-cobalt-dioxide (LCO): Has high specific energy with moderate load capabilities and modest service life. Applications include cell phones, laptops, digital cameras and wearable products.
• Lithium-manganese-cobalt-dioxide(Li-MNC): These batteries are capable of high charge and discharge currents but have low specific energy and modest service life; used for power tools, medical instruments and electric power trains.
• Lithium-ion-phosphateor lithium-phosphate (LiFePO4): These batteries are similar to lithium-manganese; they offer long cycle life, have good safety record but exhibits higher self-discharge than other Li-ion systems.
• Lithium-nickel-cobalt-aluminum-dioxide (Li-NCA): The technology is under development.
• Lithium-ion-sulfur (Li-S): These batteries are under development and the technology shall make high power batteries available for electric / plug-in electric vehicles and other high-energy applications over the next decade.

The information provided can be helpful in selecting right battery for the right purpose, since the battery chemistry is necessarily mentioned on the battery along with Amp-hr rating.

DISPOSAL OF BATTERIES

Nickel-cadmium and lead acid batteries contain hazardous material and cannot be disposed of in landfills. Nickel-metal-hydrate and lithium systems are environmentally friendly and can be disposed of with regular household items in small quantities. Authorities recommend that all batteries be recycled.

Endangered Environment – The Multi Dimensional Problem

We are all very busy in our lives and often do not find time to observe the deterioration of environment being caused by our modern lifestyle. Most of us are somewhat unaware of the power of human beings to destruct the ecosystems beyond sustainable limits. The redlines are approaching fast unless we take out time to understand the havoc being done and act to stop these blunders for the sake of preserving our environment – Our Home.

This writing is intended to identify and highlight the various dimensions of environmental deteriorations, some of which are common observation while others are not so obvious even to a keen environmental enthusiast. These environmental issues can be categorized as issues related to Built Environment, issues related to Natural Environment and global environmental issues.

Issues Related to Built Environment

• Energy related including energy conservation, commercializing of renewable energy, non-efficient energy use, environmental impact of coal industry and other fossil fuels,
• Environmental Health issues relating to air quality, asthma, electromagnetic fields, electromagnetic radiations, indoor air quality, lead poisoning and sick building syndrome
• Land use issues arise out of urban sprawl, urban heat islands, habitat fragmentation and habitat destruction
• Over population issues like burial, water crisis, overpopulation in companion animals, tragedy of the commons, gender imbalance in developing countries and sub-replacement fertility level in developed countries
• General pollution due to nonpoint source pollution, point source pollution, light pollution, noise pollution, visual pollution and interplanetary contamination
• Air pollution due to use of fossil fuels, smog, tropospheric ozone, indoor air quality, volatile organic compound and atmospheric particulate matter
• Spread of toxins due to CFCs, DDT, endocrine disruptors, dioxin, toxic heavy metals, herbicides, pesticides, toxic waste, PCB, bioaccumulation, biomagnifications and Fracking.
• Accumulation of waste in the form of electronic waste, litter, waste disposal incidents, marine debris, medical waste, landfill, leachate, incineration, Great Pacific garbage patch and exporting of hazardous waste.

Issues Related to Natural Environment

• Conservation which includes extinction of species, coral bleaching, invasive species, poaching and endangered species.
• Environmental degradation including Eutrophication or hypertrophication, habitat destruction and soda lakes
• environmental impact of hydraulic fracturing.
• Land degradation resulting from overgrazing, irrigation, monoculture, environmental effect of meat production, pesticide drift, plasticulture, land pollution and desertification
• Water pollution due to use of fossil fuels, acid rain, marine pollution, ocean dumping, oil spills, thermal pollution, urban runoff, marine debris, microplastics, ocean acidification, ship pollution, waste water, fish kill, algal boom and mercury in fish
• Resource depletion due to exploitation of natural resources and overdrafting
• Sea life depletion due to blast fishing, bottom trawling, cyanide fishing, ghost nets, illegal and unreported fishing, over fishing, shark finning and whaling
• Forrest depletion due to clear cutting, deforestation and illegal logging

Global Environmental Issues

• Climate Change which includes global warming, GHGs, sea-level rise, ocean acidification, shut-down or slowdown of Thermohaline circulation
• Genetic Engineering issues related to genetically modified food and genetic pollution
• Nuclear issues are already well known and these include nuclear fallout, nuclear meltdown, nuclear power safety issues, nuclear weapons, nuclear radiation accidents and radioactive waste management
• Ozone depletion due to CFCs and biological effects of UV exposure

It is quite unfortunate that majority of above environmental deteriorations are caused by acts of those who are more resourceful and knowledgeable among us. Let be gone be bygone. We should start spending some time to learn about these activities and make efforts to correct them. This is the only way we can preserve a better, greener and sustainable environment for our children.

LAWS OF THERMODYNAMICS SUPPORT GREEN ENERGY

Natural sciences, Physics and Chemistry, have provided us two basic laws of thermodynamics that are claimed to be obeyed by all forms of matter and energy, including living organisms.

The first law of thermodynamics is about “conservation of matter and energy,” which states that matter and energy can neither be created nor destroyed. Matter and energy can be transformed, and energy can be converted from one form into another, but the total of the equivalent amounts of both must always remain constant. When energy gets converted from one form into another, inevitably some of it is given off as heat.

The second law of thermodynamics is about “entropy increases” which states that all forms of energy tend to change spontaneously into a more dispersed, random, or less organized, form. This law defines entropy as a phenomenon of energy being constantly getting random, unavailable. Suppose you heat a pan to cook an egg, and after finishing you leave it on the stove. After some time the pan has cooled to air temperature, and the heat energy has radiated throughout the room. That heat energy is now dispersed and unavailable for cooking; the system of the pan, the room, and the heat has gone toward equilibrium. This tendency to move towards equilibrium reduces the useful availability of the energy.

An outside source of energy, with fuel or electricity, is continually required to maintain a non-equilibrium state, dispersion of heat results in a random equilibrium state. The same is true for all kinds of energy. According to second law of thermodynamics, our solar system and presumably the entire universe should theoretically become a completely random over-dispersed array of molecules and heat in the far distant future.

The more well-known first law of thermodynamics has very little to do with the energy future of our civilization. We can have all the energy in the world, but if this energy is not in a sufficiently concentrated form, it is physically impossible to make it do any meaningful work for us.

Heat Engine is the result of second law of thermodynamics. The implications of the second law of thermodynamics as it applies to our energy future is this: energy will always try to move from more concentrated forms to less concentrated forms and can only be made to do some useful work during this transition. This Second Law of Thermodynamics, developed during the 19th century, is said to be the only principle of Newtonian physics that survived the Einsteinian revolution. It is therefore an important and respected law which has a great bearing on our energy future.

Fossil fuels contain energy in concentrated form and, by burning these fuels (freeing this concentrated energy to disperse as heat throughout the biosphere) the heat engines deliver the meaningful work. In the process, however, some of the energy inevitably becomes “inaccessible” as “waste” or low-grade heat. Once dispersed, this energy achieves a state of high disorder or entropy. It cannot be reused, renewed, or recycled because it would take “more energy to reassemble it than could be recovered”. Since the thermal efficiency of the best heat engines today is around 50%, we shall always be getting waste heat (in addition to other toxic effluents) from these engines as un-available energy.

The gasoline in an automobile engine, for example, transforms into mechanical motion. As it is consumed, however, some energy is inevitably thrown off as engine heat or friction against the road. Eventually all the momentum of your car will eventually be transformed into low-grade heat. The energy is still out there but it cannot be recycled or renewed. Therefore the tank will need a refill.

Calling some sources of energy “renewable” should not be confused with the concept that waste heat or disordered and diffused energy can be reused. It can never happen and it is against the laws of natural sciences. Thinking like that would be very misleading. What is really meant by renewable energy is that some forms of energy are inexhaustible, at least for our purposes. The energy of the sun is inexhaustible with respect to life on the planet. But it is not infinite. Even when we use renewable energy, we get some of the waste heat. But this waste does not harm the environment. The reason is simple. The renewable energy systems like, concentrated solar power plants, simply concentrates the energy available in the environment for producing useful work. These systems do not burn matter to create energy.

Similarly, Hydroelectricity derives from the sun’s power to evaporate water and return it as rain. Wind comes from the sun’s uneven heating of the atmosphere. The great advantage of solar electricity is that it is strongest when it is needed most — on hot summer afternoons when electrical demand peaks. Solar electricity could definitely relieve natural gas peaking plants in powering our summer air conditioning. For this purpose we may have to prefer Concentrated Solar Power systems over PV cell systems, making a system more efficient.

There is one other source of renewable energy that is close to being as inexhaustible as the sun. That is nuclear power, which might be called “terrestrial energy.” Our planet generates huge amounts of heat. The temperature in its interior — 7,000 degrees C. — is hotter than the surface of the sun. What is the source of this heat? Some of it comes from the pressures of gravitational collapse, but almost half is generated by the disintegration of two tiny elements, uranium and thorium.

Terrestrial Energy is tapped at geothermal sites, where heat from the earth’s molten core comes in contact with groundwater. We perform this same heat exchange in what is called a “nuclear reactor.” A nuclear plant is simply the duplication of a geothermal site under more controlled conditions. Terrestrial energy does not rely on solar energy stored in carbon bonds and therefore does not put carbon dioxide back into the atmosphere. It is about as “green” as energy can get. It can probably stand by itself but is definitely worth including in any portfolio of “clean, renewable energy.”

REVERSE ENTROPY

Life is sometimes called “reverse entropy” (negentropy) because organisms maintain complex organized non-random states compared to their surroundings. But they must obey the second law of thermodynamics just as any other system of matter and energy; all organisms must work continually to build and maintain nonrandom assemblages of matter and energy locally. This process requires energy, and organisms use the energy of the decaying sun (which, of course, also obeys the second law of thermodynamics and tends toward decreasing concentration of energy) to “oppose” the second law within their own tissues by concentrating energy in their own bodies. Wherever there is a live plant or animal, there must be an energy source. Without a continued influx of energy, no organism can survive for very long. Again, this “reverse entropy” occurs only within each organism, and the overall energy relations of the entire solar system are in accord with the second law of thermodynamics, with the overall system continually becoming more and more random.

Almost all life on Earth depends on photo-synthesis, the capture of solar energy by plants. Chloroplasts are the tiny green engines that house chlorophyll and other molecular machinery enabling plants to convert solar energy into the chemical energy on which all life on Earth depends.

We may conclude fairly that laws of nature or thermodynamics are not a measure of cleanliness or greenness of any form of energy usage. Nature has created abundant energy resources and has demonstrated that all energy available cannot be converted to useful work. The waste is inherent in the nature, and the nature has its own reasons for keeping the systems like this. What we should concentrate on is not to artificially increase the rate of ENTROPY or unavailability of the energy. In my opinion, the best part of the Green Energy Living is the slowing down of the rate of energy disorder.