By Ranil Senanayake –
Any development process that relies on fossil fuels cannot be justified as sustainable, worse; it compromises the responsibilities of that nation towards the rest of the world. Any discussion on energy that fails to take in the opportunity cost and real cost of the respective energy-generating device, must be seen as lopsided and partisan. As in politics, there are various lobbies for all energy generating technologies. Each lobby will sing the praises of and down play the weaknesses of, their industry. The process of lawmaking and enforcement of public accountability will tilt in favor of the successful lobby.
For many years Sri Lanka has kept increasing its reliance on fossil generated energy. Oil, Coal or Gas, it does not make much of a difference; they are all based on fossil carbon. It must be borne in mind that all talk on the relative merits or demerits of each, still has to recognize that fact that the origin of their carbon compounds are fossil. The identification of fossil carbon is very important because there is a fundamental difference in fossil carbon and biotic carbon (the carbon of the living world) and policymakers have either ignorantly or deliberately chosen to ignore this reality. First it is important to understand Carbon.
Carbon (C), the fourth most abundant element in the Universe, after hydrogen (H), helium (He), and oxygen (O), is the building block of life. It’s the element that anchors all organic substances, from fossil fuels to DNA. On Earth, carbon cycles through the land, ocean, atmosphere, and the Earth’s interior in a major biogeochemical cycle (the circulation of chemical components through the biosphere from or to the lithosphere, atmosphere, and hydrosphere).
The global carbon cycle can be divided into two categories: the geological, which operates over large time scales (millions of years), and the biological/physical, which operates at shorter time scales (days to thousands of years).
The Global Carbon Stock
The Global Carbon Stock began Billions of years ago, as planetesimals (small bodies that formed from the solar nebula) and carbon-containing meteorites bombarded our planet’s surface, steadily increasing the planets Carbon content. Today such increments to the planets Carbon stock have ceased, but the stock has become more compartmentalized.
Since those times, carbonic acid (a weak acid derived from the reaction between atmospheric carbon dioxide [CO2] and water) has slowly but continuously combined with calcium and magnesium in the Earth’s crust to form insoluble carbonates (carbon-containing chemical compounds) through a process called weathering. Then, through the process of erosion, the carbonates are washed into the ocean and eventually settle to the bottom. The cycle continues as these materials are drawn into Earth’s mantle by subduction (a process in which one lithospheric plate descends beneath another, often as a result of folding or faulting) at the edges of continental plates. The carbon is then returned to the atmosphere as carbon dioxide during volcanic eruptions.
The balance between weathering, subduction, and volcanism controls atmospheric carbon dioxide concentrations over time periods of hundreds of millions of years. The oldest geologic sediments suggest that, before life evolved, the concentration of atmospheric carbon dioxide may have been one-hundred times that of the present, providing a substantial greenhouse effect during a time of low solar output.
The operation of life has been clearly demonstrated to change the chemistry of the atmosphere to what it is today. One of the most active systems is the oceanic plankton, photosynthetic microscopic phytoplankton produce prodigious quantities of oxygen and biomass. Small amounts of residual carbon from this plankton settle out to the ocean bottom constantly, but over long periods of time this process represents a significant removal of carbon from the atmosphere. Thus a slow transfer of the primary Carbon Dioxide from the atmosphere into the fossil reservoir, while creating an atmospheric reservoir of oxygen, had a major effect on the maintenance of a benign atmosphere for life. The Carbon that entered the fossil reservoir was removed completely from the biological cycle and became mineralized with ages of 100’s of millions of years. The fossil gas had a similar history
Coal too represents a similar process of excess Carbon Dioxide removal, especially at Devonian times with the huge vegetation mass that covered the earth absorbing Carbon Dioxide and then being mineralized as coal, removing that volume of carbon from earth’s biosphere.
These processes have been translated into vast quantities of fossilized carbon removed from the biotic/atmospheric cycles. These fossil pools have lifetimes of tens or hundreds of millions of years.
The modern carbon cycle
On land, the major exchange of carbon with the atmosphere results from photosynthesis and respiration. During the daytime in the growing season, leaves absorb sunlight and take up carbon dioxide from the atmosphere. In the oceans the planktonic cycle operate a similar Photosynthetic cycle. Both create biomass. In parallel, plants, animals and substrate microbes consume this carbon as organic matter and return carbon dioxide to the atmosphere.
The amounts of carbon that move from the atmosphere through photosynthesis, respiration, and back to the atmosphere are large and produce oscillations in atmospheric carbon dioxide concentrations. However it is very different to fossil carbon having significant chemical signature of carbon isotopes, maintains a quantity of the rare unstable isotope 14C. All carbon that lacks 14C or has a lower 13C/12C ratio does not belong in the modern or biotic cycle.
In our rush to create the new carbon economy, this very simple and fundamental fact has been ignored. Carbon that cycles through living systems represents a fixed proportion of the planetary carbon. The planetary carbon is the total found in mineral, organic and inorganic carbon.
Thus the value differential produced by these cycles, the biotic and the fossil, must be recognized in price and policy setting. The biotic carbon operates on time frames of tens or hundreds of thousands of years, fossil carbon operates in time frames of tens or hundreds of millions years. Further fossil carbon does not interact with the living or biotic cycle. Fossil carbon entering the biotic cycle is the fundamental reason as to why there is the accelerating greenhouse effect pushing climate change, but the growing of trees to compensate for fossil carbon and paying the same price as biotic carbon is tantamount to ‘carbon laundering’. There is no way to compare the carbon from oil and coal with the carbon from a forest. One has a space in the biotic cycle the other does not.
While the other options for energy generation and the delivery infrastructure are indeed areas for fruitful discussions, fossil fuels should not form any part of the future energy scenario of this nation.
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