Energy,water and global warming

At the outset it may sound odd but in reality water and energy are two sides of the same coin and both industries have a great impact on global warming.We take for example, power generation industries. Two basic requirements for any power plant are fuel and water. It does not matter what kind of fuel is used whether it is a coal based power plant, liquid fuel based plant like Naphtha, and gas based plants using piped natural gas or LNG. We will consider only power generation involving conversion of thermal energy into electrical energy. Currently more than 80% of power generation in the world is based on thermal power including nuclear plants. All thermal power plants use steam as the prime motive force to drive the turbines, gas turbine is an exception but even, in gas based plants the secondary motive force is steam using waste heat recovery boilers, in combined cycle operations. The quality of water for conversion into steam is of high quality and purer than our drinking water. The second usage of water is for cooling purpose. The water consumption by power plants using once through cooling system is 1 lit/kwhr, and by closed circuit cooling tower, it is 1.7lit/kwhr. Only about 40% power plants in Europe for example use closed circuit cooling towers and the rest use only ‘once through’ cooling systems. The total power generated in 2010 by two largest users US and China, were 3792Twhrs and 3715 Twhrs respectively. The total world power production, in 2008 was 20,262 Twhrs, using following methods. Fossil fuel: Coal 41 %, Oil 5.50%, Gas 21%, Nuclear 13% and Hydro 16%.Renewable: PV solar 0.06%, PV thermal 0.004%, Wind 1.1%, Tide 0.003 %, Geothermal 0.3%, Biomass &others 1.30%. (1Twhrs is = 1,000,000,000 kwhrs)(Ref: Wikipedia). The above statistics gives us an idea on how much water is being used by power generating plants in the world. Availability of fresh water on planet earth, is only 2.5% (96. 5% oceans, 1.70% ground water, 1.7% glaciers and ice caps, and 0.001% in the air, as vapor and clouds).The world’s precious water source is used for power generation, while millions of people do not have water to drink. The cost of bottled drinking water is US$ 0.20 /lit, in countries like, India. This situation is simply unsustainable. The prime cause of this situation is lack of technology to produce clean power without using water. The power technology we use today is based on the principle of electromagnetism invented by Michael Faraday in the year 1839. That is why, renewable energy is becoming critically important at this juncture when the world is at the cross road. Many countries are now opting for seawater desalination to meet their water demand. Desalination again is an energy intensive process. For example, 3-4 kwhrs of power is used to desalinate 1 m3 of water. This power now comes from fossil fuel fired thermal power plants, which are often co-located with desalination plants, so that all the discharge from both the plants can be easily pumped into the sea. Since the world is running out of fresh water, we have to look for attentive source of water. In countries like India, the ground water is being exploited for agricultural purpose and power generation and the ground water is getting depleted. Depleting water resources is a threat to agriculture production especially when countries depend only on monsoon rains. Unabated emission of greenhouse from fossil fuel power plants and transportation causes globe to warm. Draught and water scarcity threatens food security. It is a vicious circle. Recent delay in onset of monsoon rains in India have caused grave concern for Government and the people of India. Shortage of power and water has compounded the problem for farmers and suicide rate among the farmers is increasing at alarming rate in India. “Globally, this seems to be one of the worst summers in recorded history. The global average temperature for May was the second hottest ever since 1880 - the year records were first compiled - US National Climatic Data Centre (NCDC) has said. Only 2010 witnessed a worse May. The NCDC said such a hot May was never recorded in the northern hemisphere. No scientist will pin it on human-induced climate change - it is scientifically untenable to do so - but many affirm that these extreme weather phenomena is along predicted lines of rise in global temperatures For India, the looming possibility of El Nino dulling the monsoon rains in July-August only means things could get worse. There is half a chance that the El Nino phenomenon will pick up intensity and hit the tail of the monsoon. Thirteen of the 20 times El Nino has been recorded, it has dimmed the intensity of the monsoon, causing widespread drought. Already, the northwest region of India has suffered a rainfall deficit worse than the rest of India. But the misery of rising heat is being felt worldwide with "normal weather" systems in disarray. If large areas of the western Himalayas in Uttarakhand have suffered raging forest fires, so has the US - more than 8 lakh hectares have been engulfed in flames. The March-May period for the US has been the hottest ever. Brazil is in the midst of its worst drought in five decades with more than 1,000 towns suffering. Heavy downpours and unheard of hail has hit China and flash floods have ravaged crops in Ethiopia. The Eurasian snow cover extent has been recorded at its smallest ever for the month of May since such records were maintained for the first time in 1967. The cover was 2.67 million sqkm below average in May,theUSNCDCsaid. The southern hemisphere, where winters prevail at the moment, too has been recording extremes like never before. The Australian winter has been exceptionally cold, with the fifth coolest winter minimum temperature in over half a century of record keeping. The Antarctic sea ice extent has gone above the 1979-2000 average. In contrast, the Arctic sea ice recorded a much smaller than average extent for the same period”. (Ref: The Economic Times). The global warming has caused many natural disasters such as recent bush fires in Colorado springs in US destroying more than 300,000 houses and heavy storms in Washington causing power black outs for days together in sweltering heat. No country is immune to global warming and sea level rising. How the consequences of global warming will manifest in different forms affecting human beings and other lives is yet to be seen in years to come. That is why distributed energy systems using Hydrogen as an alternative fuel is an important step towards sustainability. One can generate Hydrogen from water, using renewable energy source like solar or wind, and store them for future usage. The stored Hydrogen can be used to generate power, as and when required, at any remote location, even where there is no grid power. The water is regenerated during this process of power generation using Fuel cell which can be recycled. There is no large consumption of water and there is no greenhouse emission. It is a clean and sustainable solution. The same stored Hydrogen can also be used to fuel their cars in the near future!

Solar Hydrogen for a cleaner future

With recent announcement of the prestigious award to NREL (National renewable energy laboratory, USA) for developing SJ3 solar cells along with their industrial partner Solar Junction, there is a new hope and expectation that PV solar will become a major source of clean energy of the future.Togather with Hydrogen as an energy carrier, the PV solar hydrogen will certainly be a game changer. With increasing efficiency of solar panel from 17.24% up to 50%, and generating high pressure hydrogen using improved solid polymer electrolyzer, the sun and water will become the future source of clean energy replacing our decade long dependency on fossil fuel. There is also a distinct possibility of converting water into hydrogen by direct sunlight using photo-electrolysis as explained in my previous article, “Can we duplicate Nature’s photosynthesis for Hydrogen production?”’ dated April 2,2012. SJ3 solar cell uses tunable band gaps, lattice matched architecture with ultra-concentration tunnel junction to achieve the highest conversion efficiency of 43.5% with a possibility to reach an efficiency of 50%.This conversion efficiency is the percentage amount of solar energy converted directly into electrical energy. Such a high efficiency is due to the lens focusing the sunlight with 418 times intensity of the sun. There is no additional cost involved except the bottom Germanium layer of three junctions with Gallium and a dash of dilute nitride alloy. This small change boosts the bottom band-gap from 0.67 eV (electron volts) to 1.0 eV.The three layered SJ3 cell captures various frequencies of sunlight at various times and conditions achieving the best efficiency of converting photons to electrons. High pressure PEM Hydrogen generators producing 99.99% purity Hydrogen at elevated pressures are already under development. With carbon fiber storage tanks up to 10,000 psi pressure ratings, Fuel cell cars will become commercial reality overtaking Lithium battery powered electrical vehicles.PV solar Hydrogen will significantly alter the transportation and stationary power generation industries in the future simply because hydrogen has the highest heat value and it is absolutely clean. Age old centralized power plants using fossil fuels with highest carbon emission and water consumption has created serious environmental problems all over the world. Coastal power plants discharge huge amount of ‘once through’ cooling water into the sea at higher temperature and at higher salinity.Tranasport industries using fossil fuels emit high greenhouse gases due to age old, inefficient combustion engines causing global warming. Low humidity, high surface temperatures, dry conditions and lightning are perfect combination of conditions for bush fires similar to the one witnessed in Colorado mountain ranges. It is a right time to adopt distributed energy systems so that individual houses and business can generate their own power using PV solar and wind Hydrogen with no transmission grids and grid failures. It is time to replace fossil fuel with sun’s light and pure water so that we can hope for a cleaner future. We have all the necessary technologies and we need a will and concerted effort to make these changes.

Renewable Hydrogen for remote power supply

PV solar is expanding as a potential renewable energy source for individual houses, and the cost of solar panels are slowly coming down as the volume of production increases. However, the intermittent nature of solar energy is still an issue, especially for off grid and remote locations. Now solar energy is stored using lead acid batteries for such applications and inverters become part of the system. The capacity of the battery bank is designed to meet the electrical demand and to absorb the fluctuation of the energy generated by solar panels and it varies from location to location. This method stores the electrical energy generated by PV solar in the form of DC current and delivers it in the form of AC current. Though this method is the simplest one for remote locations, storing solar power in the form of Hydrogen is more economical and environmentally friendly in the long run. Solar energy can directly be used to generate Hydrogen using solid polymer electrolyzers and stored in cyclinders.The stored Hydrogen can then be used to fuel a stationary Fuel cell to generate power onsite. One can design a system by integrating various components in such a way; the Hydrogen generated by solar energy is used to generate power on site as and when required. By this method one can generate required power throughout the day 24x7 irrespective of the availability of sun. The system integration involves various components supplied by various manufacturers with various specifications and the success of a system depends on the careful design using data acquired over a period of time on a specific location. Many winds to Hydrogen projects also have been tested in locations around the world.NREL (National renewable energy laboratory, USA) has conducted number of tests by integrating various components such as PV solar and wind turbines with Electrolyzers (both PEM electroylzers and alkaline electrolyzers) and Hydrogen IC engines for remote power generation as well as for fuelling vehicles with Hydrogen. Though the cost of this system is still expensive, such integration offers enormous potential as a clean energy source for remote locations without any grid power. When one takes into account the fluctuating oil prices, cost of global warming, cost of power transmissions and losses during long distance power transmission from fossil fuel power plants, Renewable Hydrogen offers the best and sustainable alternative to fossil fuels. Such a system offers complete independence, energy security, reliability and fixed power tariff. System integration of renewable energy sources for Hydrogen production and onsite power generation using Fuel cell or Hydrogen engine is the key to a successful deployment of solar and wind energy for rural electrification and to remote islands. Such system will offer greater return on investment even to supply power to the grid based on power purchase agreements with Government and private companies. Renewable Hydrogen is the only viable solution for clean power of the future and sooner we embrace this integrated solution better for a cleaner future. Government and private companies investing on oil and gas explorations can focus their attention in developing renewable Hydrogen based solutions so that the cost of Hydrogen can become competitive to fossil fuel. Once the cost of Hydrogen reaches parity with cost of fossil fuel then, it will set the beginning of a green revolution in clean energy.

Lithium batteries and Electric cars

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 require rechargeable batteries with capacity to quickly store and discharge electric energy over multiple cycles. There are 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 go up substantially in the coming years. It is estimated that a battery capable of providing 100miles range will contain 3.4 to 12.7 Kgs 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 now 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.

Ocean acidifiction- a threat to food security

The unabated emission of Carbon dioxide by burning fossil fuels by human beings is altering the chemistry of our oceans at an unprecedented rate in the last 65 million years. When excess Carbon dioxide is absorbed by seawater it forms Carbonic acid, which is weak and unstable and increase the Hydrogen ion concentration in seawater. It decreases the pH value. The seawater is alkaline and the mean ocean surface pH was measured at 8.2 in 1750.This acidity has increased by 30% in recent times due to absorption of vast amount of man-made carbon dioxide since pre-industrial time. The amount estimated are about 500 Giga tones or 25% emitted into the atmosphere. According to UN report: “If we continue at this rate the ocean pH will decline by a further 0.3 by the end of this century, an unprecedented 150% increase in ocean acidity. This rate of change has not been experienced for around 65 million years, since the dinosaurs became extinct. Such a major change in basic ocean chemistry is likely to have substantial implications for ocean life in the future, especially organisms that require calcium carbonate to build shells or skeletons. Not all organisms will react at the same rate or in the same way to decreasing carbonate ion concentration. There are three naturally occurring forms of calcium carbonate used by marine organisms to build shells, plates or skeletons: calcite, aragonite and high magnesium calcite. For example, microscopic plants called coccolithophores surround themselves with protective calcite plates; aragonite is used by periods to build their shells and corals use it to make their skeletons that help to form reefs; while some echinoderms – starfish, sea urchins, brittle stars - utilize magnesium calcite to form their exoskeletons. Magnesium calcite is more soluble and sensitive to ocean acidification than aragonite; with calcite being the least soluble of the three. A lowering of pH and reduction of carbonate ions will make it more difficult for organisms to sustain their calcified shells, and in under saturated conditions, waters become corrosive to these minerals. Additionally, most multicellular marine organisms have evolved a regulatory system to maintain the hydrogen ion balance of their internal fluids14 and spend energy doing this so an increase in hydrogen ions in seawater means that they will have to divert more energy away from important processes such as growth and reproduction to do this. However, studies of mussels, crab and sea urchin species have shown they have only a partial or no, compensation mechanism15 potentially making them more vulnerable than those organisms that possess a compensation mechanism”.(Ref:UNEO) The contribution of marine food in the form of Protein to food security is substantial. Fish supplies about 15% of animal protein for about 3 billion people worldwide. Further one billion people depend on fisheries for their primary source of Protein. Steadily increasing population is pushing the demand for protein even further, while the fish stock is dwindling in many parts of the world due to over fishing and environmental degradation. “Productivity ‘hotspots’ such as upwelling regions where cold water is rich in both nutrients and CO2, coastal seas, fronts, estuaries and sub-polar regions often supply the main protein source for coastal communities. However, many of these areas are also projected to be very vulnerable to ocean acidification this century.” (Source: UNEP) Global warming has a much wider ramification than originally thought. It is not just warming the globe but threatens the food security and our own survival as human beings.