UPSC Prelims S.E.E. Snapshot: Dimethyl Ether, CPI overhaul, Tar Balls — quick look

SCIENCE

Dimethyl Ether (DME)

— DME is a synthetically produced alternative fuel that can be directly used in specially designed compression ignition diesel engines for various purposes. Under normal atmospheric conditions, DME is a colourless gas. It is used extensively in the chemical industry and as an aerosol propellant, solvent, fuel, and refrigerant.

— DME exhibits comparable calorific value and similarity of its thermal efficiency to traditional fuels; It is a clean-burning fuel with low emission and low particulate matter.

— Most importantly, it has already been used as an ozone-friendly aerosol propellant to replace ozone-destroying chlorofluorocarbons (CFCs). Therefore, it can also be used as a refrigerant. Also, it is an essential intermediate for producing valuable chemicals such as lower olefins, dimethyl sulfate, and methyl acetate, which can help to boost the economy of the nation.

(Image- Google NotebookLM generated)

— DME can be considered as a ‘Second Generation fuel/bio-fuel’ with a slight ethereal odour. It liquefies under pressure (10 bar at 40oC), and these properties of DME are like propane. Moreover, it is relatively inert, non-corrosive, non-carcinogenic, almost non-toxic, and does not form peroxides by prolonged exposure to air. 

— Its physio-chemical properties make it a suitable substitute (or blending agent) for LPG. Therefore, DME can be used as a fuel in household cooking gas and industries. 

—Notably, Methane does not directly produce DME, but serves as a starting material. It is first converted into syngas (CO and H2), and then into methanol, which is used to produce DME. Methane can be sourced from both fossil fuels and renewable sources, DME production is flexible and future-ready.

📍UPSC Twist Points– DME VS LPG

— LPG is a relatively clean, portable, and efficient energy source. It is colourless and odourless and a strong “stenching” agent is added so that even a very small leak can be easily detected. 

—  At a normal temperature, LPG is a gas. When subjected to modest pressure or cooling, it transforms into a liquid. As a liquid, it is easy to transport and store. 

—  LPG is an energy-rich fuel source with a higher calorific value per unit than other commonly used fuels. 

ECONOMY

CPI with new Base year

Core Concept

— Inflation refers to the rate at which the general price level for goods and services increases over a period of time, causing a decrease in purchasing power of money or real income. There are different methods for measuring inflation such as Consumer Price Index, Wholesale Price Index (WPI), GDP deflator, and more, with each focusing on a specific aspect of price changes.

— Consumer Price Index (CPI) Inflation relates to consumer prices of all goods purchased by the consumer, which may be either domestically produced or imported.

— CPI inflation is the most important economic indicator in the country as it directly influences the level of interest rates set by the Reserve Bank of India (RBI). The central bank has a legal mandate to target a CPI inflation rate of 4% in the medium term within a tolerance band of 2-6%. 

— The newest CPI inflation comes after years of work by the statistics ministry to update the base year for prices of the CPI to 2024 from 2012, reconstitute the consumption basket based on the results of the 2023-24 Household Consumption Expenditure Survey (HCES), so that prices are measured as per the latest consumption patterns and not the 2011-12 survey.

— The new CPI with the changed “base year” of 2024, which means that the price index is given a value of 100 for 2024 and changes from these price levels are then calculated to arrive at inflation rates for each good or service. 

— The new CPI basket contains 358 goods and services, up from 299 in the erstwhile basket. This new CPI has included rural house rent for the first time to improve coverage of rural housing consumption.

— The CPI 2024 series adopts the Classification of Individual Consumption According to Purpose (COICOP) 2018, replacing the earlier structure comprising six broad groups. These were the six broad groups—Food and beverages, Pan, tobacco and intoxicants, Clothing and footwear, Housing, Fuel and light and Miscellaneous (services such as education, health care etc.).

— CPI 2024 uses the latest classification system developed by the United Nations Statistics Division. According to the MoSPI, “under the revised framework, expenditure is classified into 12 divisions at the first level, 43 groups, 92 classes, 162 subclasses, enabling and 358 items at the last level of hierarchy. 

📍UPSC Twist Points– CPI vs WPI and GDP Deflator

— Wholesale Price Index (WPI): While the CPI measures the price changes in the retail market (maximum retail prices{MRP}, inclusive of taxes), the WPI measures the price changes in the wholesale market. Say, for example, the price of a commodity (such as onions) would vary depending on the fact that it is bought from the wholesale market or retail market.

— GDP deflator: The GDP deflator (also called implicit price deflator) is the ratio of the value of goods and services an economy produces in a particular year at current prices to that at prices prevailing during any other reference (base) year.

ENVIRONMENT

Tar Balls 

Core Concept

— Tar balls are dark-coloured, sticky, weathered residue from oil leaks, spills, effluents, and accidents that cause onshore and offshore marine pollution. 

Tarballs are dark-coloured, sticky balls of oil that form when crude oil floats on the ocean surface. (Courtesy: Shaunak Modi, Director, Coastal Conservation Foundation)

— Tar balls are formed by weathering of crude oil in marine environments. According to NOAA, when crude oil (or a heavier refined product) floats on the ocean surface, its physical characteristics change. During the first few hours of a spill, the oil spreads into a thin slick.

— Winds and waves tear the slick into smaller patches that are scattered over a much wider area. Various physical, chemical, and biological processes change the appearance of the oil. These processes are generally called “weathering.”

— Weathering processes eventually create a tarball or flattened tar patty that can be hard and crusty on the outside and soft and gooey on the inside. 

(Image- Google NotebookLM generated)

— Some of the tar balls are as big as a basketball while others are smaller globules. Tarballs are usually coin-sized and are found strewn on the beaches. However, over the years, they have become as big as basketballs and can weigh as much as 6-7 kgs.

— Tar balls affect flora and fauna and the tourism industry through its deposition on beaches, especially India’s western coast, where tar balls wash ashore during the monsoon due to strong winds and currents.

— These tar balls contain toxic contaminants, such as heavy metals, trace elements, and persistent organic pollutants, and pose environmental and health risks.

📍UPSC Twist Points: Tar balls vs Microplastics

— Microplastics are tiny particles of less than five millimetres in size. They broadly classified into primary microplastics – intentionally produced microplastics such as those found in cosmetics – and secondary microplastics – resulting from the decomposition of larger plastic materials.

— The small, shiny particles advertised as “cooling crystals” in certain toothpastes qualify as microplastics if the ingredients of the toothpaste mention “polyethylene”.

— These plastics are non-biodegradable and remain in the environment for a long time after their improper disposal. They degrade into smaller particles through physical, chemical, or biological processes and persist in the environment due to their slow degradation rate.

Prelims Practice MCQ

Let’s see how much can you recall

With reference to the following, consider the statements:

1. Dimethyl Ether can be directly produced from methane without any intermediate stages.

2. Consumer Price Index measures price changes of goods and services and forms the basis for inflation targeting by the Reserve Bank of India.

3. Tar balls are formed due to the weathering of crude oil in marine environments.

How many of the statements given above are correct?

(a) Only one

(b) Only two

(c) All three

(d) None

UPSC Prelims ‘SEE’ Snapshot: Talking cars, GDP rebasing and Nor’westers — quick look 

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