Cooling
India in a 'greener' & more sustainable manner
There is a apocryphal story attributed to a former southeast
Asian political leader who when asked as to what was the single most important
technological development of recent times, retorted that it was air
conditioning. While this may be some exaggeration, there is no denying that air
conditioners (ACs) have made at least the tropics liveable and raised
productivity. Indeed, the energy required to cool (or heat) homes and offices
accounts for a significant portion of global energy consumption and making it
more efficient is an important component of national strategies to reducing
carbon emissions.
Demand for ACs is soaring in India, driven by rising
aspirations, increasing affordability, and better availability of uninterrupted
power across the country. The room AC stock in the country has increased from
2-mn units in 2006 to about 30-mn, and there does not seem to be a let up in
demand. What was once considered a luxury, to be used sparingly to keep
electricity bills low, is now deemed a convenience or even a necessity, and
usage norms are becoming a lot more flexible.
Environmental impact
But ACs place a considerable burden on the environment. They are
power guzzlers and just as importantly the refrigerant gases used in them –
typically hydrocarbons containing fluorine or chlorine or both – have
additional environmental impacts. Several have a high Global Warming Potential
(GWP) – several hundreds of times that of carbon dioxide (CO2), the
most commonly produced greenhouse gas – and many have been shown to deplete the
ozone layer, a thin layer of the gas in the upper atmosphere that protects the
planet against harmful ultraviolet (UV) radiation.
The problem of ozone depletion has been known for some time, and
a global treaty – the Montreal Protocol – first addressed the issue by
restricting and eventually banning usage of chlorofluorocarbons (CFCs), which
were shown to be notoriously persistent molecules capable of punching a
sizeable ‘hole’ in the ozone layer. Thanks to the initiative, this ‘hole’ has
repaired itself at least to some extent, but the job is not yet done, as their
replacements such as hydrochlorochlorofluorocarbons (HCFCs) and
hydrofluorcarbons (HFCs) have also been shown to have some (albeit lower) ozone
depleting potential (ODP) and GWP.
From Montreal to Kigali
In a follow-up to the Montreal pact, in 2016, 197 countries met
in Kigali (Rwanda) and agreed to a global phase-out of HFCs. Compliance to this
pact will also have significant global impact: India alone is expected to avoid
use of HFCs equivalent to anywhere between 2-6 bn tonnes of CO2 in
fulfilling its commitment, and about a quarter of this will come from reduction
in the use of HFCs for room ACs. If the phase-out is faster – say, inline with
commitments by developing countries – the benefits to the planet will be even
greater.
Twin-track progress
There are two tracks by which room ACs can be made greener:
making them more energy efficient and switching to coolants with low GWP and
ODP.
According to estimates made by the Lawrence Berkeley National
Laboratory, improving energy efficiency will have a far greater impact –
perhaps three times as much as switching refrigerants. It calculates that if
India’s AC stock were to become 30% more efficient (from 2015 levels) in terms
of energy consumption, annual CO2 emissions will fall by
180-mtpa – roughly equivalent to 10% of the country’s Nationally Determined
Contribution (NDCs) as per the to which India is a signatory. The commitment,
it may be recalled, calls for a 33-35% decrease in the carbon intensity of the
country’s Gross Domestic Product (GDP) by 2030.
The low GWP alternatives now offered in the room AC market
include hydrocarbon HC-290 (better known as propane), with a GWP of just three;
and the transitional refrigerant HFC-32, with GWP of 677, compared to the
refrigerants HCFC-22 (GWP of 1,760) and HFC 410-A (GWP of 1,924).
According to a recent report ‘Improving Air Conditioners in
India – Cooling India With Less Warming’ published by The Energy Research
Institute (TERI), more than 50 room AC models are currently available in the
country that have Indian Seasonal Energy Efficiency Ratios (ISEERs) – a measure
of energy efficiency – of 4.0 or greater, with the best-in-class from Daikin,
Godrej, Panasonic, LG and Hitachi having reached an ISEER level of 5.8 and
upwards. These energy-efficient room ACs typically use HC-290 (up to
1.5-tonnes) or HFC-32 (up to 1.8-tonnes).
Further gains possible
The Montreal Protocol’s Technology and Economic Assessment Panel
(TEAP) estimates that foreseeable technological innovations in room ACs will
afford additional 30-40% energy savings from that afforded by current best
available technologies, without prohibitive expense or difficulty.
In India, more energy-efficient Inverter ACs are taking
market-shares from the more predominant fixed speed ACs. Early indications for
this summer point to a 20% growth in Inverter AC sales, as compared to the
previous year. Overall, in 2018, Inverter ACs are expected to account for about
40% of total room AC sales – a figure that is expected to rise to 65% by 2020,
according to the TERI report, based on feedback from industry.
Comprehensive strategy needed
But cooling living and working spaces through room ACs has to be
seen as part of a comprehensive strategy to utilise energy efficiently in
buildings – residential and commercial. It must also cover use of efficient
lighting (including natural lighting), natural cooling systems, use of
renewable energy (in particular solar energy), and advanced materials that keep
the insides of a building cool during summers and warm during winters.
Significant role for chemical industry
The chemical industry has much to contribute here. High
performance insulation systems are but one example of the industry’s products
that are now widely deployed, particularly in the developed world. Materials
such as expanded polystyrene (EPS) and polyurethane foams (PUFs); durable and
aesthetic door & window profiles made of unplasticised polyvinyl chloride
(uPVC) that offer a snug fit; and sealants & adhesives made from epoxy
resins that plug air leaks, are but a few offerings that are now widely used in
construction.
Likewise, additives to coatings are now available that can
reflect the infrared components of the incident sunlight, and so reduce the
load on traditional air conditioning systems. These are typically put on
rooftops and walls to reflect heat away. Even more exotic technologies such as
liquid crystal windows that can turn from fully transparent to opaque,
depending on the brightness needed, are now just making their mark in markets.
The benefits from such integrated approaches are considerable.
The German chemical company, Bayer, for instance has a building in the
outskirts of New Delhi, which uses several of these technologies – including
PUFs and polycarbonate windows – to cut down energy consumption to a level that
is more than compensated by the renewable power generated by the solar panels
installed on its roofs. Admittedly, the capital costs of such construction are
higher, but with scale-up, rising energy costs and incentives for ‘green’
buildings the payback times will get shorter.
Government initiatives in setting standards will be a big boost
for all such ‘green’ initiatives. Revision in building codes prescribing
insulation levels for large commercial buildings, to start with, could lead to
a scale-up of capacities amongst solution providers and instil confidence
amongst smaller, more risk-averse users. Mandating a minimum ISEER of 4.0 for
room AC manufacturers could raise the bar of energy efficiency, as will the
introduction of a low-GWP refrigerant label to encourage wider adoption of
‘greener’ refrigerant systems.
In India, space conditioning – mainly cooling – will account for
two-third of energy demand in buildings by 2047, unless energy efficiency gains
are pursued. The technologies to enable significant energy savings are very
much available today and represent fairly easy pickings to transition to a
‘cool’ and more sustainable way of living and working!
News
Cooling India in a 'greener' &
more sustainable manner - Ravi Raghavan
Author: Ravi Raghavan
There is a apocryphal story attributed to a former southeast
Asian political leader who when asked as to what was the single most important
technological development of recent times, retorted that it was air
conditioning. While this may be some exaggeration, there is no denying that air
conditioners (ACs) have made at least the tropics liveable and raised
productivity. Indeed, the energy required to cool (or heat) homes and offices
accounts for a significant portion of global energy consumption and making it
more efficient is an important component of national strategies to reducing
carbon emissions.
Demand for ACs is soaring in India, driven by rising
aspirations, increasing affordability, and better availability of uninterrupted
power across the country. The room AC stock in the country has increased from
2-mn units in 2006 to about 30-mn, and there does not seem to be a let up in
demand. What was once considered a luxury, to be used sparingly to keep
electricity bills low, is now deemed a convenience or even a necessity, and
usage norms are becoming a lot more flexible.
Environmental impact
But ACs place a considerable burden on the environment. They are
power guzzlers and just as importantly the refrigerant gases used in them –
typically hydrocarbons containing fluorine or chlorine or both – have
additional environmental impacts. Several have a high Global Warming Potential
(GWP) – several hundreds of times that of carbon dioxide (CO2), the
most commonly produced greenhouse gas – and many have been shown to deplete the
ozone layer, a thin layer of the gas in the upper atmosphere that protects the
planet against harmful ultraviolet (UV) radiation.
The problem of ozone depletion has been known for some time, and
a global treaty – the Montreal Protocol – first addressed the issue by
restricting and eventually banning usage of chlorofluorocarbons (CFCs), which
were shown to be notoriously persistent molecules capable of punching a
sizeable ‘hole’ in the ozone layer. Thanks to the initiative, this ‘hole’ has
repaired itself at least to some extent, but the job is not yet done, as their
replacements such as hydrochlorochlorofluorocarbons (HCFCs) and
hydrofluorcarbons (HFCs) have also been shown to have some (albeit lower) ozone
depleting potential (ODP) and GWP.
From Montreal to Kigali
In a follow-up to the Montreal pact, in 2016, 197 countries met
in Kigali (Rwanda) and agreed to a global phase-out of HFCs. Compliance to this
pact will also have significant global impact: India alone is expected to avoid
use of HFCs equivalent to anywhere between 2-6 bn tonnes of CO2 in
fulfilling its commitment, and about a quarter of this will come from reduction
in the use of HFCs for room ACs. If the phase-out is faster – say, inline with
commitments by developing countries – the benefits to the planet will be even
greater.
Twin-track progress
There are two tracks by which room ACs can be made greener:
making them more energy efficient and switching to coolants with low GWP and
ODP.
According to estimates made by the Lawrence Berkeley National
Laboratory, improving energy efficiency will have a far greater impact –
perhaps three times as much as switching refrigerants. It calculates that if
India’s AC stock were to become 30% more efficient (from 2015 levels) in terms
of energy consumption, annual CO2 emissions will fall by
180-mtpa – roughly equivalent to 10% of the country’s Nationally Determined
Contribution (NDCs) as per the to which India is a signatory. The commitment,
it may be recalled, calls for a 33-35% decrease in the carbon intensity of the
country’s Gross Domestic Product (GDP) by 2030.
The low GWP alternatives now offered in the room AC market
include hydrocarbon HC-290 (better known as propane), with a GWP of just three;
and the transitional refrigerant HFC-32, with GWP of 677, compared to the
refrigerants HCFC-22 (GWP of 1,760) and HFC 410-A (GWP of 1,924).
According to a recent report ‘Improving Air Conditioners in
India – Cooling India With Less Warming’ published by The Energy Research
Institute (TERI), more than 50 room AC models are currently available in the
country that have Indian Seasonal Energy Efficiency Ratios (ISEERs) – a measure
of energy efficiency – of 4.0 or greater, with the best-in-class from Daikin,
Godrej, Panasonic, LG and Hitachi having reached an ISEER level of 5.8 and
upwards. These energy-efficient room ACs typically use HC-290 (up to
1.5-tonnes) or HFC-32 (up to 1.8-tonnes).
Further gains possible
The Montreal Protocol’s Technology and Economic Assessment Panel
(TEAP) estimates that foreseeable technological innovations in room ACs will
afford additional 30-40% energy savings from that afforded by current best
available technologies, without prohibitive expense or difficulty.
In India, more energy-efficient Inverter ACs are taking
market-shares from the more predominant fixed speed ACs. Early indications for
this summer point to a 20% growth in Inverter AC sales, as compared to the
previous year. Overall, in 2018, Inverter ACs are expected to account for about
40% of total room AC sales – a figure that is expected to rise to 65% by 2020,
according to the TERI report, based on feedback from industry.
Comprehensive strategy needed
But cooling living and working spaces through room ACs has to be
seen as part of a comprehensive strategy to utilise energy efficiently in
buildings – residential and commercial. It must also cover use of efficient
lighting (including natural lighting), natural cooling systems, use of
renewable energy (in particular solar energy), and advanced materials that keep
the insides of a building cool during summers and warm during winters.
Significant role for chemical industry
The chemical industry has much to contribute here. High
performance insulation systems are but one example of the industry’s products
that are now widely deployed, particularly in the developed world. Materials
such as expanded polystyrene (EPS) and polyurethane foams (PUFs); durable and
aesthetic door & window profiles made of unplasticised polyvinyl chloride
(uPVC) that offer a snug fit; and sealants & adhesives made from epoxy
resins that plug air leaks, are but a few offerings that are now widely used in
construction.
Likewise, additives to coatings are now available that can
reflect the infrared components of the incident sunlight, and so reduce the
load on traditional air conditioning systems. These are typically put on
rooftops and walls to reflect heat away. Even more exotic technologies such as
liquid crystal windows that can turn from fully transparent to opaque,
depending on the brightness needed, are now just making their mark in markets.
The benefits from such integrated approaches are considerable.
The German chemical company, Bayer, for instance has a building in the
outskirts of New Delhi, which uses several of these technologies – including
PUFs and polycarbonate windows – to cut down energy consumption to a level that
is more than compensated by the renewable power generated by the solar panels
installed on its roofs. Admittedly, the capital costs of such construction are
higher, but with scale-up, rising energy costs and incentives for ‘green’
buildings the payback times will get shorter.
Government initiatives in setting standards will be a big boost
for all such ‘green’ initiatives. Revision in building codes prescribing
insulation levels for large commercial buildings, to start with, could lead to
a scale-up of capacities amongst solution providers and instil confidence
amongst smaller, more risk-averse users. Mandating a minimum ISEER of 4.0 for
room AC manufacturers could raise the bar of energy efficiency, as will the
introduction of a low-GWP refrigerant label to encourage wider adoption of
‘greener’ refrigerant systems.
In India, space conditioning – mainly cooling – will account for
two-third of energy demand in buildings by 2047, unless energy efficiency gains
are pursued. The technologies to enable significant energy savings are very much
available today and represent fairly easy pickings to transition to a ‘cool’
and more sustainable way of living and working!
- Ravi Raghavan
8MAY18
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