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A new concept known as “hydraulic fracturing “ to enhance the recovery of land fill gas from new and existing land fill sites have been tested jointly by a Dutch and  Canadian companies. They claim it is now possible to recover such gas economically and liquefy them into Bio-LNG to be used as a fuel for vehicles and to generate power.

Most biofuels around the world are now made from energy crops like wheat, maize, palm oil, rapeseed oil etc and only  a minor part is  made from waste. But such a practice in not sustainable in the long run considering the anticipated food shortage due to climate changes.   The EU wants to ban biofuels that use too much agricultural land and encourage production of biofuels that do not use food material but waste materials. Therefore there is a need to collect methane gas that is emitted by land fill sites more efficiently and economically and to compete with fossil fuels.

There are about 150,000 landfills in Europe with about 3–5 trillion cubic meters of waste (Haskoning 2011). All landfills emit landfill gas; the contribution of methane emissions from landfills is estimated to be between 30 and 70 million tons each year. Landfills contributed an estimated 450 to 650 billion cubic feet of methane per year (in 2000) in the USA. One can either flare landfill gas or make electricity with landfill gas. But it is prudent to produce the cleanest and cheapest liquid biofuel namely “Bio-LNG”.

Landfill gas generation: how do these bugs do their work?

Researchers had a hard time figuring out why landfills do not start out as a friendly environment for the organisms that produce methane. Now new research from North Carolina State University points to one species of microbe that is paving the way for other methane producers. The starting bug has been found. That opens the door to engineer better landfills with better production management. One can imagine a landfill with real economic prospects other than getting the trash out of sight. The NCSU researchers found that an anaerobic bacterium called Methanosarcina barkeri appears to be the key microbe. The following steps are involved in the formation of landfill gas is shown in the diagram

Phase 1: oxygen disappears, and nitrogen

Phase 2: hydrogen is produced and CO2 production increases rapidly.

Phase 3: methane production rises and CO2 production decreases.

Phase 4: methane production can rise till 60%.

Phases 1-3 typically last for 5-7 years.

Phase 4 can continue for decades, rate of decline depending on content.

Installation of landfill gas collection system

A quantity of wells is drilled; the wells are (inter) connected with a pipeline system. Gas is guided from the wells to a facility, where it is flared or burnt to generate electricity. A biogas engine exhibits 30-40% efficiency. Landfills often lack access to the grid and there is usually no use for the heat.

The alternative: make bio-LNG instead and transport the bio-LNG for use in heavy-duty vehicles and ships or applications where you can use all electricity and heat.

Bio-LNG: what is it?

Bio-LNG is liquid bio-methane (also: LBM). It is made from biogas. Biogas is produced by anaerobic digestion. All organic waste can rot and can produce biogas, the bacteria does the work. Therefore biogas is the cheapest and cleanest biofuel  that can be generated without competing  with food or land use. For the first time there is a biofuel, bio-LNG, a better quality fuel than fossil fuel.

The bio-LNG production process

Landfill gas is produced by anaerobic fermentation in the landfill. The aim is to produce a constant flow of biogas with high methane content. The biogas must be upgraded, i.e. removal of H2S, CO2 and trace elements;

In landfills also siloxanes, nitrogen and Cl/F gases. The bio-methane must be purified (maximum 25/50ppm CO2, no water) to prepare for liquefaction. The cold box liquefies pure biomethane to bio-LNG

Small scale bio-LNG production using smarter methods.

•Use upgrading modules that do not cost much energy.

•Membranes which can upgrade to 98-99.5 % methane are suitable.

•Use a method for advanced upgrading that is low on energy demand.

•Use a fluid / solid that is allowed to be dumped at the site.

•Use cold boxes that are easy to install and low on power demand.

•Use LNG tank trucks as storage and distribution units.

•See if co-produced CO2 can be sold and used in greenhouses or elsewhere.

•Look carefully at the history and present status of the landfill.

What was holding back more projects?

Most flows of landfill gas are small (hundreds of Nm3/hour), so economy of scale is generally not favorable. Technology in upgrading and liquefaction has evolved, but the investments for small flows during decades cannot be paid back.

Now there is a solution: enhanced gas recovery by hydraulic fracturing. Holland Innovation Team and Fracrite Environmental Ltd. (Canada) has developed a method to increase gas extraction from landfill 3-5 times.

Hydraulic fracturing increases landfill gas yield and therefore economy of scale for bio-LNG production

The method consists of a set of drilling from which at certain dept the landfill is hydraulically broken. This means a set of circular horizontal fractures are created from the well at preferred depths. Sand or other materials are injected into the fractures. Gas gathers from below in the created interlayer and flows into the drilled well. In this way a “guiding” circuit for landfill gas is created. With a 3-5 fold quantity of gas, economy of scale for bio-LNG production will be reached rapidly. Considering the multitude of landfills worldwide this hydraulic fracturing method in combination with containerized upgrading and liquefaction units offers huge potential. The method is cost effective, especially at virgin landfills, but also at landfill with decreasing amounts of landfill gas.

Landfill gas fracturing pilot (2009).

• Landfill operational from 1961-2005

• 3 gas turbines, only 1 or 2 in operation at any time due to low gas extraction rates

• Only 12 of 60 landfill gas extraction wells still producing methane

• Objective of pilot was to assess whether fracturing would enhance methane extraction rates

Field program and preliminary result

Two new wells drilled into municipal wastes and fractured (FW60, FW61). Sand Fractures at 6, 8, 10, 12 m depth in wastes with a fracture radius of 6 m. Balance gases believed to be due to oxygenation effects during leachate and

Groundwater pumping.

Note: this is entirely different from deep fracking in case of shale gas!

Conceptual Bioreactor Design

 The conceptual design is shown in the figures.There are anaerobic conditions below the groundwater table, but permeability decreases because of compaction of the waste. Permeability increases after fracking and so does the quantity of landfill gas and leachate.

Using the leachate by injecting this above the groundwater table will introduce anaerobic conditions in an area where up till then oxygen prevailed and so prevented landfill gas formation

It can also be done in such a systematic way, that all leachate which is extracted, will be disposed off in the shallow surrounding wells above the groundwater table.

One well below the groundwater table is fracked, the leachate is injected at the corners of a square around the deeper well. Sewage sludge and bacteria can be added to increase yield further

Improving the business case further

A 3-5 fold increased biogas flow will improve the business case due to increasing

Economy of scale. The method will also improve landfill quality and prepare the landfill for other uses.

When the landfill gas stream dries up after 5 years or so, the next landfill can be served by relocating the containerized modules (cold boxes and upgrading modules). The company is upgrading with a new method developed in-house, and improving landfill gas yield by fracking with smart materials. EC recommendations to count land fill gas quadrupled for renewable fuels target and the superior footprint of bio-LNG production from landfills are beneficial for immediate start-ups

Conclusions and recommendations

Landfills emit landfill gas. Landfill gas is a good source for production of bio-LNG. Upgrading and liquefaction techniques are developing fast and decreasing in price. Hydraulic fracturing can improve landfill gas yield such that economy of scale is reached sooner. Hydraulic fracturing can also introduce anaerobic conditions by injecting leachate, sewage sludge and bacteria above the groundwater table. The concept is optimized to extract most of the landfill gas in a period of five years and upgrade and liquefy this to bio-LNG in containerized modules.

Holland Innovation Team and Fracrite aim at a production price of less than €0.40 per kilo (€400/ton) of bio-LNG, which is now equivalent to LNG fossil prices in Europe and considerably lower than LNG prices in Asia, with a payback time of only a few years.

(Source:Holland Innovation Team)

 

 

The largest power outage that affected 650 million people in India recently was major news around the world. Power outage is common in many countries including industrialized countries during the times of natural disasters such as cyclones, typhoons and flooding. But the power outage that happened in India was purely man-made. It was not just an accident but a culmination of series of failures as the result of many years of negligence, incompetency and wrong policies. Supplying an uninterrupted power for a democratic country like India with 1.2 billion people with 5-8% annual economic growth, mostly run by Governments of various political parties in various states is by no means an easy task. While one can understand the complexities of the problems involved in power generation and distribution, there are certain fundamental rules that can be followed to avoid such recurrence.

The supply and demand gap for power in India is increasing at an accelerated rate due to economic growth but the power generation and distribution capacity do not match this growth. Most of the power infrastructures in India are owned by Governments who control the power generation, distribution, operation and maintenance, financing power projects, supplying power generation equipment, supplying consumables, supplying fuel, transportation of fuel and revenue collection. The entire system is based on the policy of ‘socialistic democracy’, after the independence from the British, though economic liberalization and globalization is relatively a new phenomenon in India. Since every department of power infrastructure is controlled by Government, there is a lack of accountability and competition. Many private companies and foreign companies do not take part in tendering process because it is a futile exercise. Some smart multinational companies set up their manufacturing facilities in India, often in collaboration with Governments to get an entry into one of the largest market in the world. Indigenous Coal is the dominant fuel widely used for power generation though the quality of coal is very low, with ash content as high as 30%.The calorific value of such coal hardly exceeds 3000 kcal/kg, which means more quantity of coal  is required than any other fuel to generate same amount of power. Such coal generates not only low power but also generates a huge amount of ‘fly ash’ (the ash content is the coal comes out as fly ash) causing pollution and waste disposal problems. Large piles of fly ash and age-old cooling towers with a large pool of stagnant water are common sights in many power plants in India. Such low-cost coal does not make any economic sense when considering the amount of fly ash disposal cost and environmental damages. Thanks to research institutions that have developed methods to utilize fly ash in production of Portland cement. The indigenous low-grade coal is the fuel of choice by Indian power industries, though many plants have started importing coal recently from Indonesia and South Africa. Indigenous low-grade coal and cooling water from rivers and underground sources are two major pollutants in India. Water is allocated for power plants at the cost of agriculture. There is a shortage of drinking water in many cities as well as irrigation water for agriculture.

Since most of the power infrastructures are owned by Governments there is a tendency to adopt populace policies  such as power subsidies, free water and power for farmers, low power tariffs etc, making such projects economically unviable in the long run. Most of the State Electricity boards in India are running at a loss and such accumulated losses amounts to staggering figures. The Central electricity authority regulates the power tariff. They calculate the cost of power generation based on specific fuel and fix the power tariff that companies can charge their consumers even before the plant is set up. Most of such tariffs are based on their experience using indigenous low-grade coal and transport cost which are often impractical. Such low power tariffs are not remunerative for private companies and many foreign companies do not invest in large capital-intensive power projects in India for the same reason.

The best option for the Governments to solve energy problems in India is to open to foreign investments and allow latest technologies in power generation and distribution. It is up to the investing companies to decide the right type of fuel, right of equipment, source and procurement, power technology to be adopted and finally the tariff.  India has come a long way since independence and Governments should focus on Governing rather than managing and controlling infrastructure projects. The latest scam widely debated in Indian media is “Coal scam’. It is time India moves away from fossil fuel and allow foreign investments and technologies in renewable energy projects freely without any interference. India needs large investments in building power and water infrastructures and it possible to attract foreign investment only by infusing confidence in investing companies. It is not just the size of the market that is to be attractive for investors but  they also need a conducive, fair and friendly   environment for such investment.

People in the chemical field will understand the concept of ‘irreversibility’. Certain chemical reactions can go only in one direction and but not in the reverse direction. But some reactions can go on either direction and we can manipulate such reactions to our advantages. This concept has been successfully used in designing many chemical reactions in the past and many innovative industrial and consumer products emerged out of it. But such irreversible reactions also have irreversible consequences because it can irreversibly damage the environment we live in. There is no way such damage can be reversed. That is why a new branch of science called ‘Green Chemistry’ is now emerging to address some of the damages caused by irreversible chemical reactions. It also helps to substitute many synthetic products with natural products. In the past many food colors were made out of coal-tar known as coal-tar dyes. These dyes are used even now in many commercial products. Most of such applications were merely based on commercial attractiveness rather than health issues. Many such products have deleterious health effects and few of them are carcinogenic. We learnt from past mistakes and moved on to new products with less health hazards. But the commercial world has grown into a power lobby who can even decide the fate of a country by influencing political leaders. Today our commercial and financial world has grown so powerful that they can even decides who can be the next president of a country rather than people and policies. They can even manipulate people’s opinion with powerful advertisements and propaganda tactics by flexing their financial muscles.

Combustion of fossil fuel is one such example of ‘irreversibility’ because once we combust coal, oil or  gas,  it will be decomposed into oxides of Carbon, oxide of  Nitrogen and also oxides of Sulfur and Phosphorous depending upon the source of fossil fuel  and purification methods used. These greenhouse gases once emitted into the atmosphere we cannot recover them back. Coal once combusted it is no longer a coal. This critical fact is going to decide our future world for generations to come. Can we bring back billions of tons of Carbon we already emitted into the atmosphere from the time of our industrial revolution? Politicians will pretend not to answer these question and financial and industries lobby will evade these question by highlighting the ‘advancement made by industrial revolutions’. People need electricity and they have neither time nor resources to find an alternative on their own. It is open and free for all. People can be skeptical about these issues because it is ‘inconvenient for them’ to change But can we sustain such a situation?

Irreversibility does not confine only to chemical reactions but also for the environment and sustainability because all are intricately interconnected.Minig industries have scared the earth, power plants polluted the air with greenhouse emission and chemical industries polluted water and these damages are irreversible. When minerals become metals, buried coal becomes power and water becomes toxic effluent then we leave behind an earth that will be uninhabitable for our future generations and all the living species in the world. Is it sustainable and can we call it progress and prosperity? Once we lose pristine Nature by our irreversible actions then that is a perfect recipe for a disaster and no science or technology can save human species from extinction. One need not be scientist to understand these simple facts of life. Each traditional land owners such as Aborigines of Australia or Indians of America and shamans of Indonesia have traditionally known and passed on their knowledge for generations. They too are slowly becoming extinct species in our scientific world because of our irreversible actions. Renewability is the key to sustainability because renewability does not cause irreversible damage to Nature.

 

All existing power generation technologies including nuclear power plants uses heat generation as a starting point. The heat is used to generate steam which acts as a motive force to run an alternator to produces electricity. We combust fossil fuels such as coal oil and gas to generate above heat which also emits greenhouse gases such as oxides of Carbon and Nitrogen. As I have disused in my earlier article, we did not develop a technology to generate heat without combusting a fossil fuel earlier. This was due to cheap and easy availability of fossil fuel. The potential danger of emitting greenhouse gases into the atmosphere was not realized until recently when scientists pointed out the consequences of carbon build up in the atmosphere. The growth of population and industries around the world pushed the demand for fossil fuels over a period which enhanced the Carbon build up in the atmosphere.

But now Concentrated Solar Power (CSP) systems have been developed to capture the heat of the sun more efficiently and the potential temperature of solar thermal can reach up to 550. This dramatic improvement is the efficiency of solar thermal has opened up new avenues of power generation as well as other applications. “CSP is being widely commercialized and the CSP market has seen about 740 MW of generating capacity added between 2007 and the end of 2010. More than half of this (about 478 MW) was installed during 2010, bringing the global total to 1095 MW. Spain added 400 MW in 2010, taking the global lead with a total of 632 MW, while the US ended the year with 509 MW after adding 78 MW, including two fossil–CSP hybrid plants”. (Ref: Wikipedia)

“CSP growth is expected to continue at a fast pace. As of April 2011, another 946 MW of capacity was under construction in Spain with total new capacity of 1,789 MW expected to be in operation by the end of 2013. A further 1.5 GW of parabolic-trough and power-tower plants were under construction in the US, and contracts signed for at least another 6.2 GW. Interest is also notable in North Africa and the Middle East, as well as India and China. The global market has been dominated by parabolic-trough plants, which account for 90 percent of CSP plants.As of 9 September 2009, the cost of building a CSP station was typically about US$2.50 to $4 per  watt, the fuel (the sun’s radiation) is free. Thus a 250 MW CSP station would have cost $600–1000 million to build. That works out to $0.12 to $0.18/kwt. New CSP stations may be economically competitive with fossil fuels. Nathaniel Bullard,” a solar analyst at Bloomberg

New Energy Finance, has calculated that the cost of electricity at the Ivanpah Solar Power Facility, a project under construction in Southern California, will be lower than that from  photovoltaic power and about the same as that from natural gas  However, in November 2011, Google announced that they would not invest further in CSP projects due to the rapid price decline of photovoltaics. Google spent $168 million on Bright Source IRENA has published on June 2012 a series of studies titled: “Renewable Energy Cost Analysis”. The CSP study shows the cost of both building and operation of CSP plants. Costs are expected to decrease, but there are insufficient installations to clearly establish the learning curve. As of March 2012, there was 1.9 GW of CSP installed, with 1.8 GW of that being parabolic trough” Ref: Wikipedia.

One Canadian company has demonstrated to generate Hydrogen from water using a catalytic thermolysis using sun’s high temepertaure.The same company has also demonstrated generating base load power using conventional steam turbine by  CSP using parabolic troughs. They store sun’s thermal energy using a proprietary thermic fluid and use them during night times to generate continuous power. The company offers to set up CSP plants of various capacities from 15Mw up to 500Mw.

 

 

 

 

 

 

 

Renewable Hydrogen offers the most potential energy source of the future for the following reasons. Hydrogen has the highest heat value compared to rest of the fossil fuels such as Diesel, petrol or butane. It does not emit any greenhouse gases on combustion. It can readily be generated from water using your roof mounted solar panels. The electrical efficiency of fuel cell using Hydrogen as a fuel is more than 55% compared to 35% with diesel or petrol engine. It is an ideal fuel that can be used for CHP applications. By properly designing a system for a home, one can generate power as well as use the waste heat to heat or air-condition your home. It offers complete independence from the grid and offers complete insulation from fluctuating oil and gas prices. By installing a renewable Hydrogen facility at your home, you can not only generate Electricity for your home but also fuel your Hydrogen car. The system can be easily automated so that it can take care of your complete power need as well as your fuel requirement for your Hydrogen car. Unlike Electric cars, you can fill two cylinders of a Hydrogen car which will give a mileage of 200miles.You can also charge your electric car with Fuel cell DC power.

Renewable Hydrogen can address all the problems we are currently facing with fossil fuel using centralized power generation and distribution. It will not generate any noise or create any pollution to the environment. It does not need large amount of water. With increasing efficiency of solar panels coming into the market the cost of renewable Hydrogen power will become competitive to grid power. Unlike photovoltaic power, the excess solar power is stored in the form of Hydrogen and there is no need for deep cycle batteries and its maintenance and disposal. It is a one step solution for all the energy problems each one of us is facing. The only drawback with any renewable energy source is its intermittent nature and it can be easily addressed by building enough storage capacity for Hydrogen. Storing large amount of energy is easy compared to battery storage.

The attached ‘You Tube’ video footage show how Solar Hydrogen can be used to power your home and fuel your Hydrogen car. Individual homes and business can be specifically designed based on their power and fuel requirements.

The world is debating on how to cut carbon emission and avert the disastrous consequences of global warming. But the emissions from fossil fuels continue unabated while the impact of global warming is being felt all over the world by changing weathers such as flood and draught. It is very clear that the current rate of carbon emission cannot be contained by merely promoting renewable energy at the current rate. Solar, wind, geothermal, ocean wave and OTEC (ocean thermal energy conversion) offer clean alternative energy but now their total combined percentage of energy generation   is only less than 20% of the total power generation. The rate of Carbon reduction by  renewable energy  do not match  the rate of Carbon emission increase by existing and newly built  fossil power generation and transportation, to keep up the current level of Carbon in the atmosphere. The crux of the problem is the rate of speed with which we can cut the Carbon emission in the stipulated time frame. It is unlikely to happen without active participation of industrialized countries such as US, China, India, Japan, EU and Australia by signing a legally binding agreement in reducing their Carbon emissions to an accepted level. However, they can cut their emissions by increasing the efficiency of their existing power generation and consumption by innovative means.

One potential method of carbon reduction is by substituting fossil fuels with biomass in power generation and transportation. By using this method the energy efficiency is increased from current level of 33% to 50-60% in power generation by using gasification technologies and using Hydrogen for transportation. The Fixed carbon in coal is about 70% while the Carbon content in a biomass is only 0.475 X B (B-mass of oven-dry biomass). For example, the moisture content of a dry wood is about 19%,which means the Carbon mass is only 38% in the biomass. To substitute fossil fuels, the world will need massive amounts of biomass. The current consumption of coal worldwide is 6.647 billion tons/yr  (Source:charts bin.com)and the world will need at least 13 billion tons/yr of biomass to substitute coal .The total biomass available in the world in the form of forest is 420 billion tons which means about 3% of the forest in the world will be required to substitute current level of coal consumption. This is based on the assumption that all bioenergy is based on gasification of wood mass. But in reality there are several other methods of bioenergy such as biogas, biofuels such as alcohol and bio-diesel from vegetable oils etc, which will complement biogasification to cut Carbon emission.

Another potential method is to capture and recover Carbon from existing fossil fuel power plants. The recovered Carbon dioxide has wider industrial applications such as industrial refrigeration and in chemical process industries such as Urea plant. Absorption of Carbon dioxide from flue gas using solvents such as MEA (mono ethanolamine) is a well established technology. The solvent MEA will dissolve Carbon dioxide from the flue gas and the absorbed carbon dioxide will be stripped in a distillation column to separate absorbed carbon dioxide and the solvent. The recovered solvent will be reused.

The carbon emission can be reduced by employing various combinations of methods such as anaerobic digestion of organic matters, generation of syngas by gasification of biomass, production of biofuels, along with other forms of renewable energy sources mentioned above. As I have discussed in my previous articles, Hydrogen is the main source of energy in all forms of Carbon based fuels and generating Hydrogen from water using renewable energy source is one of the most potential and expeditious option to reduce Carbon emission.

Carbon neutral biomass is becoming a potential alternative energy source for fossil fuels in our Carbon constrained economy. More and more waste –to-energy projects is implemented all over the world due to the availability of biomass on a larger scale; thanks to the increasing population and farming activities. New technological developments are taking place side by side to enhance the quality of Biogas for power generation. Distributed power generation using biogas is an ideal method for rural electrification especially, where grid power is unreliable or unavailable. Countries like India which is predominantly an agricultural country, requires steady power for irrigation as well as domestic power and fuel for her villages. Large quantity of biomass in the form of agriculture waste, animal wastes and domestic effluent from sewage treatment plants are readily available for generation of biogas. However, generation of biogas of specified quality is a critical factor in utilizing such large quantities of biomass. In fact, large quantity of biomass can be sensibly used for both power generations as well as for the production of value added chemicals, which are otherwise produced from fossil fuels, by simply integrating suitable technologies and methods depending upon the quantity and quality of biomass available at a specific location. Necessary technology is available to integrate biomass gasification plants with existing coal or oil based power plants as well as with chemical plants such as Methanol and Urea. By such integration, one can gradually change from fossil fuel economy to biofuel economy without incurring very large capital investments and infrastructural changes. For example, a coal or oil-fired power plant can be easily integrated with a large-scale biomass plant so that our dependency on coal or oil can be gradually eliminated.

Generation of biogas using anaerobic digestion is a common method. But this method generates biogas with 60% Methane content only, and it has to be enriched to more than 95% Methane content and free from Sulfur compounds, so that it can substitute piped natural gas with high calorific value or LPG (liquefied petroleum gas). Several methods of biogas purification are available but chemical-free methods such as pressurized water absorption or cryogenic separation or hollow fiber membrane separation are preferred choices.

The resulting purified biogas can be stored under pressure in tanks and supplied to each house through underground pipelines for heating and cooking. Small business and commercial establishments can generate their own power from this gas using spark-ignited reciprocating gas engines (lean burnt gas engines) or micro turbines or PAFCs (phosphoric acid fuel cells) and use the waste heat to air-condition their premises using absorption chillers. In tropical countries like India, such method of distributed power generation is absolutely necessary to eliminate blackouts and grid failures. By using this method, the rural population need not depend upon the state-owned grid supplies but generate their own power and generate their own gas, and need not depend on the supply of rationed LPG cylinders for cooking. If the volume of Bio-methane gas is large enough, then it can also be liquefied into a liquified bio-methane gas (LBG) similar to LNG and LPG. The volume of biomethane gas will be reduced by 600 times, on liquefaction. It can be distributed in small cryogenic cylinders and tanks just like a diesel fuel. The rural population can use this liquid bio-methane gas as a fuel for transportation like cars, trucks, buses, and farm equipment like tractors and even scooters and auto-rickshaws.

Alternatively, large-scale biomass can be converted into syngas by gasification methods so that resulting biomass can be used as a fuel as well as raw materials to manufacture various chemicals. By gasification methods, the biomass can be converted into a syngas (a mixture of Hydrogen and Carbon monoxide) and free from sulfur and other contaminants. Syngas can be directly used for power generation using engines and gas turbines.

Hydrogen rich syngas is a more value added product and serves not only as a fuel for power generation, but also for cooking, heating and cooling. A schematic flow diagram Fig 3,  Fig4 and Fig 6 (Ref: Mitsubishi Heavy Industries Review) shows how gasification of biomass to syngas can  compete with existing fossil fuels for various applications such as for power generation, as a raw material for various chemical synthesis and as a fuel for cooking, heating and cooling and finally as a liquid fuel for transportation. Bio-gasification has a potential to transform our fossil fuel dependant world into Carbon-free world and to help us to mitigate the global warming.

All forms of renewable energy sources are intermittent by nature and therefore storage becomes essential. Energy is used mainly for power generation and transportation and the growth of these two industries are closely linked with development of energy storage technologies and devices. Electrical energy is conventionally stored using storage batteries. Batteries are electrochemical devices in which electrical energy is stored in the form of chemical energy, which is then converted into electrical energy at the time of usage.

Batteries are key components in cars such as Hybrid electric vehicles, Plug-in Hybrid electrical vehicles and Electrical vehicles – all store energy for vehicle propulsion. Hybrid vehicle rely on internal combustion engine as the primary source of energy and use a battery to store excess energy generated during vehicle braking or produced by engine. The stored energy provides power to an electric motor that provides acceleration or provides limited power to the propulsion. Plug-in hybrid incorporates higher capacity battery than Hybrid eclectic vehicles, which are charged externally and used as a primary source of power for longer duration and at higher speed than it is required for Hybrid electric vehicles. In Electric cars, battery is the sole power source.

All electric vehicles need rechargeable batteries with capacity to quickly store and discharge electric energy over multiple cycles. There are a wide range of batteries and chemistries available in the market. The most common NiMH (Nickel Metal Hydride) used Cathode materials called AB5; A is typically a rare earth material containing lanthanum, cerium, neodymium and praseodymium; while B is a combination of nickel, cobalt, manganese and/or aluminum. Current generation Hybrid vehicles use several Kg of rare earth materials.

Lithium ion battery offers better energy density, cold weather performance, abuse tolerance and discharge rates compared to NiMH batteries. With increasing usage of electrical vehicles the demand for lithium-ion batteries and Lithium is likely to g up substantially in the coming years. It is estimated that a battery capable of providing 100miles range will contain 3.4 to 12.7 Kegs of Lithium depending upon the lithium-ion chemistry and the battery range. Lithium -ion batteries are also used in renewable energy industries such as solar and wind but Lead-acid batteries are used widely due to lower cost.

The lithium for Cathode and electrolyte is produced from Lithium Carbonate which is now produced using naturally occurring brines by solar evaporation with subsequent chemical precipitation. The naturally occurring brine such as in Atacama in Chile is now the main source of commercial Lithium. The brine is a mixture of various chlorides including Lithium chloride, which is allowed to evaporate by solar heat over a period of 18-20 months. The concentrated lithium chloride is then transferred to a production unit where it is chemically reacted with Sodium carbonate to precipitate Lithium Carbonate. Chile is the largest producers of Lithium carbonate.

Though Lithium ion batteries are likely to dominate electric vehicle markets in the future, the supply of Lithium remains limited. Alternative sources of Lithium are natural ores such as Spodumene.Many companies around the world, including couple of companies in Australia are in the process of extracting Lithium from such ores.

Manufacturers produce battery cells from anode, cathode and electrolyte materials. All lithium-ion batteries use some form of lithium in the cathode and electrolyte materials, while anodes are generally graphite based and contain no lithium.   These cells are connected in series inside a battery housing to form a complete battery pack. Despite lithium’s importance for batteries, it represents a relatively small fraction of the cost of both the battery cell and the final battery cost.

“Various programs seek to recover and recycle lithium-ion batteries. These include prominently placed recycling drop-off locations in retail establishments for consumer electronics batteries, as well as recent efforts to promote recycling of EV and PHEV batteries as these vehicles enter the market in larger numbers (Hamilton 2009). Current recycling programs focus more on preventing improper disposal of hazardous battery materials and recovering battery materials that are more valuable than lithium. However, if lithium recovery becomes more cost-effective, recycling programs and design features provide a mechanism to enable larger scale lithium recycling. Another potential application for lithium batteries that have reached the end of their useful life for vehicle applications is in stationery applications such as grid storage.

The supply chain for many types of batteries involves multiple, geographically distributed steps and it overlaps with the production supply chains of other potential critical materials, such as cobalt, which are also used in battery production. Lithium titanate batteries use a lithium titanium oxide anode and have been mentioned as a potential candidate for automotive use (Gains 2010), despite being limited by a low cell voltage compared to other lithium-ion battery chemistries.” (Ref: Centre for Transportation, Argonne National Laboratory)

Usage of power for extraction of Lithium from naturally occurring brines is lower compared to extraction from mineral sources because bulk of the heat for evaporation of brine is supplied by solar heat. However Lithium ion batteries can serve only as a storage medium and the real power has to be generated either by burning fossil fuel or from using renewable energy sources. Governments around the world should make usage of renewable power mandatory for users of Electrical vehicles. Otherwise introduction of Lithium ion battery without such regulation will only enhance carbon emission from fossil fuels.

 

We now generate electric city from heat, obtained by combustion of fossil fuel such as coal, oil and gas. But such combustion generates not only heat but also greenhouse gases such as Carbon dioxide and oxides of Nirogen.The only alternative to generate power without any greenhouse gas emission is to use a fuel with zero carbon. However, oxides of Nitrogen will still be an issue as long as we use air for combustion because atmospheric air has almost 79% Nitrogen and 21% oxygen. Therefore it becomes necessary to use an alternative fuel as well as an alternative power generation technology in the future to mitigate greenhouse problems.

Hydrogen is an ideal fuel to mitigate greenhouse gases because combustion of Hydrogen with oxygen from air generates only water that is recyclable. Combining Hydrogen with Oxygen using Fuel cell, an electrochemical device is certainly an elegant solution to address greenhouse problems. But why Hydrogen and Fuel cell are not commonly available? Hydrogen is not available freely even though it is abundantly available in nature. It is available as a compound such as water (H2O) or Methane (CH4) and Ammonia (NH3). First we have to isolate Hydrogen from this compound as free Hydrogen and then store it under pressure. Hydrogen can easily form an explosive mixture with Oxygen and it requires careful handling. Moreover it is a very light gas and can easily escape. It has to be compressed and stored under high pressure.

Generation of pure Hydrogen from water using Electrolysis requires more electricity that it can generate. However, Hydrogen cost can be reduced using renewable energy source such as solar thermal. The solar thermal can also supply thermal energy for decomposing Ammonia into Hydrogen and Nitrogen as well as to supply endothermic heat necessary for steam reformation of natural gas into Hydrogen. On-site Hydrogen generation using solar thermal using either electricity or heat can become a commercial reality. Hydrogen generation at higher temperatures such as Ammonia decomposition or steam reformation can be directly used in Fuel cell such as Phosphoric acid Fuel cell.

Phosphoric acid fuel cell is a proven and tested commercial Fuel cell that is used for base load power generation. It is also used for CHP applications. Hydrogen generation using solar thermal and power generation using Fuel cell is already a commercial reality and also an elegant solution to mitigate greenhouse gases. Large scale deployment of Fuel cell and solar thermal will also cut the cost of installations and running cost competing with fossil fuel.Fuecell technology has a potential to become a common solution for both power generation and transportation.

While Government can encourage renewable energy by subsidizing PV solar panels and discourage fossil fuel by imposing carbon tax, they should give preference and higher tariff for power purchase from Solar thermal and Fuel cell power generators. This will encourage large-scale deployment of Fuel cell as a potential base load power source.

Renewability and sustainability are two critical factors that will decide the future course of the world. We have to learn from Nature how sun is able to sustain life on earth for millions of years without the slightest hitch. The sun provides light energy for the photosynthesis to generate Carbohydrate using carbon dioxide from the atmosphere and water. The green pigment in the leaves of the plant ‘Chlorophyll’ catalalyses the photosynthesis. The plant grows and serves as food for animals. After certain period both the plant and animal dies and becomes carbon. New plants and animals are produced and the cycle continues. The dead plant decays and serves as manure for the new plant. A sequence of combinations of atmosphere, photosynthesis, micronutrients in the soil, absorption of carbon dioxide from air and release of Oxygen into the atmosphere, food production, life sustainenace, death and decay play like a symphony in an orchestra. Microorganisms too play their role in this cycle.

It is obvious from the above process that life cycle is based on ‘Renewability’.The  death and decay of the old plant gives way to the birth of new plant and new cycle. There is nothing static .It is a dynamic and cyclic process, where ‘Renewability’ is the key. Only with renewability the process can ‘sustain’. Without a cyclic nature, the process will end abruptly. In fact ‘renewability’ and ‘sustainability’ are closely linked.

When we try to develop a new source of energy it is absolutely critical that such a source is renewable and available directly from Nature. Sun is the prime source of such energy, though it is also available in other forms such as wind, wave, ocean thermal etc. Such renewability can come only from Nature because human life in intricately linked with Nature such as earth, sun and wind. Everything that happens in Nature is to support life on earth and not to destroy. This is a fundamental issue.

When we dig out Carbon from the earth  that was deeply buried by Nature and burn them, we release Carbon dioxide as well as Oxide of Nirtogen.Though our primary interest is only heat, we also create by-products such as greenhouse gases that upset the natural equilibrium. Nature can make some adjustments in order to maintain equilibrium; but when this limit exceeds, the equilibrium is upset creating a new environment, which may be alien to human life. This is unsustainable. Nature does not burn organic matter indiscriminately to generate Carbon dioxide to promote photosynthesis. It judiciously and delicately uses atmospheric Carbon dioxide without the slightest disturbance to the equilibrium. Many chemical reactions are irreversible and can cause irreversible damages, similar to ‘radiation’ from a nuclear reaction.

Whatever we do in the name of science, we will have to face their consequences, if we fail to understand the process of Nature completely and thoroughly. Fossil fuel sources are limited and burning them away to meet our energy demands is neither prudent nor sustainable. Human greed has no limit. We live in a finite world with finite resources and there is no place for infinite greed and destruction. There is no solution in Science for human greed.

 

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