THE HINDU EDITORIAL SUNDAY – MAY, 1, 2022
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Intense heat What is driving
up temperatures beyond normal in north, west, central and east India? JACOB KOSHY The story so far: India is in the
throes of an unusually long series of heatwaves that began in the end of
March and scorched north India for most of April. The India Meteorological
Department (IMD) said April was the hottest in northwest India in 122 years.
It has also been an unusually hot April – with temperatures touching above 40֯
C – in large parts of Bihar, Jharkhand and West above Bengal. How widespread is
the heatwave? -Records from IMD
suggest that the average maximum temperature till April 27 was 35.7֯C, the highest in five years for this month.
In Madhya Pradesh, Rajasthan, Punjab, and Gujarat, the average maximum
temperature in April 2022 so far has been the highest since 1951; while it
has been the second highest in Delhi, Uttar Pradesh, and Haryana. In most of
these States, the temperature has been consistently above 42֯C and around 5.6 degrees above normal for
this time of the year.
Latest IMD forecasts say heat wave conditions prevail in many parts of
Punjab, northwest Rajasthan and Vidarbha, Maharashtra. It’s also unusually
hot in parts of Himachal Pradesh, west Madhya Pradesh, Jharkhand, Bihar,
Gangetic West Bengal and Odisha. Maximum temperatures were 43-46 degree
Celsius over most parts of Rajasthan, Vidarbha Madhya Pradesh and east Uttar
Pradesh, in many parts of Gujarat and interior Odisha; in some parts of
central Maharashtra and in isolated pockets of Bihar, Jharkhand and interior
Gangetic West Bengal. Temperatures were over 40-43 degree Celsius in most
parts of Haryana-Delhi, Punjab and in isolated pockets of west Uttar Pradesh,
Chhattisgarh Marathwada, Telangana and Rayalaseema. These scorching
conditions are expected to continue until the middle of next week until, the
agency says, a western disturbance from West Asia brings rain to parts of
north and north-western India. While it is to unusual for the latter half of
April to be dry and hot in most of north, west and central India, this year
is unusual in that this follows the warmest March in 121 years with the
maximum temperature across the country nearly 1.86֯C above normal. How are heatwaves
defined? -A heatwave is
declared when the maximum temperature is over 40֯C and at least 4.5 notches above normal. A severe heatwave is
declared if the departure from normal temperature is more than 6.4 degrees,
according to the IMD. Based on absolute recorded temperatures, a heatwave is
declared when an area logs a maximum temperature of 45֯C. A severe heatwave is declared if the maximum temperature
crosses 47 degrees. Is climate change
responsible? -The heat-trapping
consequences of global warming imply that climate extremes such as heatwaves
are expected to rise in frequency. Instances of extreme rainfall, as well as
longer rainless spells are expected, according to assessments by the
Intergovernmental Panel on Climate Change. The main reason for the scorching
heat in the northern parts of the country is lack of rainfall. Usually,
periods of high temperature are punctuated by periodic episodes of rain but
this was largely absent during March and April. Ironically, April also saw
maximum instances of extreme rainfall since 2018 though it was concentrated
in the south and north-eastern India. The rain-bearing western disturbances
originate because of temperature gradients between the northernmost parts of
the globe and the latitudes passing through West Asia. Weaker gradients mean
weaker rains. This March and April, cooler than normal conditions in the
Pacific Ocean failed to aid rainfall in north India. What impact do
heatwaves have over India? -Research through
the years shows that the number of heatwave days in India is increasing every
decade. From 413 in 1981-90 to 575 in 2001-10, the number of days that see
extremely hot days is persistently increasing at 103 weather stations. Some
parts along eastern India, such as Andhra Pradesh, Telangana and Odisha, also
register higher humidity along with high temperatures, leading to the rise in
a condition called ‘wet bulb’ temperature, that at its mildest can cause
extreme discomfort and at its worst cause dehydration and death. Heatwaves
have killed more than 17,000 people in 50 years in India, according to a
research study by IMD scientists. However, the intensity and length of
heatwaves don’t have a direct connection to India’s monsoon that sets in over
Kerala in June. What is being
done to buffer against high temperatures? -Over the years,
forecast systems have improved that allow heatwave warnings to be disseminated
via electronic channels and phones instantaneously. Many State governments
across the country have declared school holidays; some have highlighted the
dangers of working outdoors during the day. Many State governments award
monetary compensation for deaths linked to heatwaves. Why are electric
vehicles catching fire? -Is the battery causing the problem? What safety measures need to be
followed to prevent explosions? VENKAT SRINIVASAN The story so far: The Union
government has constituted an expert panel to probe the recent series of
battery explosions in electric vehicles (EVs).Manufacturers such as Okinawa
and Pure EV have recalled some batches of electric scooters after their died
at his home in Telangana’s Nizamabad district after the battery of an
electric scooter exploded while being charged. After the enquiry, the Ministry
of Road Transport intends to issue guidelines for EVs, including tests for
compliance with safety norms. Why is the world poised to transition to
electric vehicles? -The growing concern over climate change
has led to global efforts to electrify the transportation sector. In
parallel, cost of Li-ion (Lithium-ion) battery technology has decreased by a
staggering order of magnitude in the past decade. The convergence of these
two factors has resulted in a unique time in our history where we are at the
cusp of a dramatic transition in the transportation sector, with electric
vehicles poised to replace petrol vehicles. The world has taken note of this moment
with governments providing incentives to usher in the transition of private
industry ramping up plans for capturing the market. There is a worldwide race
emerging, with vehicles companies, battery manufacturers, and material
suppliers vying with each complex device requiring a level of sophistication
that can takes years to perfect. Hurrying the development of this complex
technology without careful safeguards can lead to increasing safety
incidents, as evidenced recently on India roads. What goes into a
Li-ion battery? -Every Li-ion battery consists of three
active components: the anode, typically graphite; the cathode, typically
based on a nickel, cobalt, and manganese-based inorganic solvent. Battery
manufacturing is a complex operation involving forming sheets of the anode
and held apart by a thin separator. Separators, about 15 microns in thickness –
about a fifth of the thickness of the human hair – perform the critical
function of preventing the anode and cathode from shorting. Accidental
shorting of the electrodes is a known cause of fires in Li-ion cells. It is
important that the various layers are assembled with high precision with
tight tolerances maintained throughout the manufacturing process. Safety
features, such as thermal switches that turn off if the battery overheats,
are added as the sandwich is packaged into a battery cell. Battery cells are assembled into modules
and then further assembled into packs. Li-ion batteries require tight control
on the state of charge and the temperature of operation to enhance safety and
increase usable life, achieved by adding multiple sensors. Packs are designed
to ensure uniform temperature profile with minimal thermal variation during
operation. Ensuring robust detection, coupled with battery management systems
that interpret the data and change operation based on changes to the
batteries state, remains critically important in enhancing battery
performance. Battery packs are integrated into the
vehicle in unique form factors depending on the design of the vehicle. The
location of the battery should protect it from external penetration; ensure
passenger safety while talking into consideration the overall weight
distribution. Close interaction between vehicle manufacturers and battery
manufacturers is essential so that the whole is greater than the sum of the
parts. There are multiple trade-offs in this
complex ecosystem: engineering higher safety often results in higher costs
and lower driving range. In this competitive landscape where companies are
vying for market share, a race to the bottom can compromise safety. What causes
battery fires? -While Li-ion batteries are complex,
over the last three decades numerous companies have perfected the art of
manufacturing high-quality cells and integrating them into vehicles with
minimal safety concerns. The energy density of petrol is five hundred times
that of a typical Li-ion battery, therefore safety should be manageable if
robust controls are in place. However, batteries do store energy in a small
package and if the energy is released in an uncontrolled fashion, the thermal
even can be significant. Battery fires, like others fires, occur
due to the convergence of three parts of the “fire triangle”: heat, oxygen,
and fuel. If an adverse event such as a short circuit occurs in the battery,
the internal temperature can raise as the anode and cathode release their
energy through the short. This, in turn, can lead to a series of reactions
from the battery materials, especially the cathode, that release heat in an
uncontrolled manner, along with oxygen. Such events also rupture the sealed
battery further exposing the components to outside air and the second part of
the fire triangle, namely, oxygen. The final component of the triangle is the
liquid electrolyte, which is flammable and serves as a fuel. The combination
leads to a catastrophic failure of the battery instantaneously and
explosively. The
trigger for such events can be a result of internal shorts (like a
manufacturing defect that results in sharp objects penetrating the
separator), external events (an accident leading to puncture of the cell and
shorting of the electrodes), overcharging the battery which leads to heat
releasing reactions on the cathode (by a faulty battery management system
that does not shut down charging despite the battery achieving its designed
charge state), or bad thermal design at the module and pack level (by not
allowing the battery internal heat to be released). Any of these triggers may
cascade into a significant safety incident. (see graphic). Are battery fires inevitable? -Over the past three decades, Li-ion
batteries have proved to be extremely safe, with the industry increasing
controls as safety incidents have surfaced. Safety is a must and is an
important consideration that battery and vehicle manufacturers can design for
at multiple levels from the choice of battery material to designs at the
cell, pack, and vehicle level. Preventing fires requires breaking the
fire triangle. Battery cathodes are a leading cause of the heat release. Some
cathodes, such as ones with lower nickel content or moving to iron phosphate,
can increase safety. Tightly controlled manufacturing will prevent accidental
shorts in the cells, eliminating a leading cause of fires. Many companies now
add a ceramic layer on the separator to mechanically prevent shorts. Sensing
the state of the battery and integrating this data into sophisticated battery
management systems is an important aspect of design. Protecting the cell with
robust thermal management is critical, especially in India where ambient
temperatures are high. Finally, battery packs need to be protected from
external penetration. Any large-scale manufacturing process inevitably has a
certain percentage of defects; therefore, such steps are needed to minimize the
number of adverse events. Long-term changes are also under way.
Safety remains a concern for Li-ion manufacturers worldwide especially as
cell sizes become larger for applications such as solar-connected storage.
Companies are developing internal “switches” that turn off parts of the
battery that undergo thermal events to stop them at their inception. Research
is now underway to replace the flammable liquid electrolyte with a solid electrolyte
to eliminate one part of the fire triangle. A similar thread of research is
the development of nonflammable liquid electrolytes. All these changes
promise to remove the threat of battery fires as the roll out of mass
electrification takes place.
Engineering safety requires commitment from all parts of the battery
supply chain and tight integration between vehicle companies and battery
companies. Further, regulators play an important role, providing the testing
and certification needed to ensure that technology innovations perform at the
level that is promised. Li-ion batteries are not forgiving of shoddy
engineering and approaches that rely on cutting corners. Companies with
tightly controlled manufacturing with years of experience can maintain the
number of adverse safety incidents to a minimum. Such batteries maybe more
expensive, but safety should not be “just another” metric. Rather, ensuring
safety should be the priority for manufacturers. States vs Centre: who increased fuel tax
rate? What is the stand of States ruled by BJP rivals on reduction of
value-added tax to bring down petrol prices? VIGNESH RADHAKRISHNAN The story so far: Petrol is retailing
at more than 100 rupees a litre across India. The primary reason for the increase
in pump prices over the past few years is the gradual rise in the Union
government’s excise duty component. The excise duty was cut by 5 rupees per
litre last November. While some States followed with a cut in value-added tax
(VAT), many others did not. On Wednesday, Prime Minister Narendra Modi said
fuel prices were to high in some non-BJP-ruled States as they did not “pass
the benefits of the Centre’s excise duty cut” to consumers. He said States
such as Maharashtra, West Bengal, Telangana, Andhra Pradesh, Tamil Nadu,
Kerala and Jharkhand did not reduce VAT last November while Karnataka and
Gujarat did so. By how much has the Central tax on fuel
increased? -In October 2018, the Central excise
duty on petrol amounted to 17.98 rupees per litre. In February 2022, it
increased to 27.9 rupees per litre of petrol. In this period, the Centre’s
tax component expanded by about 10 rupees per litre of petrol. By how much has the tax levied by States
risen? -As on February 2019, Kerala charged
30.08% as sales tax along with 1 rupee a litre additional sales tax, plus 1%
cess. Telangana charged 35.2%. West Bengal charged 25% or 13.12 rupees per
litre whichever was higher, with minor additional components. None of the
three States had made any increases to the rates till April 2022. Tamil Nadu
charged 34% VAT on petrol as on February 2019. In 2022, the tax structure has
changed to 13% VAT plus 11.52 rupees a litre. In the period under review, Andhra Pradesh
and Maharashtra (Mumbai)’s tax on petrol has risen by 3 rupees a litre,
whereas Karnataka’s sales tax rate declined from 32% to 25.92%, and Gujarat’s
from 17% to 13.7%. In the non-BJP-ruled States, in this period, tax rates
increased between nil and 3 rupees per litre, whereas in the BJP-ruled
States, tax rates declined. How can the impact of States’ taxes and the
Centre’s excise duties on petrol be measured? -One way to do this would be to compare
the Centre’s excise duty collections on crude oil and petroleum products, and
the States’ VAT collections on petroleum products, as a percentage of GDP. In
the same period, States’ tax collections have marginally declined from 1.1%
of GDP to 1.02% of GDP. Another measure would be to compare the Centre’s tax
share in the retail price of petrol with State’s tax share. For instance, in
Delhi, the Centre’s tax share currently forms 26.4% of the retail price. In
May 2014 it was around 14%. The State’s tax share currently forms 16.25% of
the retail price, compared with 17% in May 2014. So, both in terms of percentage
of GDP and retail prices, the States’ tax collections have remained the same
or even slightly declined, whereas the Centre’s tax collections have climbed
sharply. |
