scenario in India
Energy has become one of the important assets for a
developing country like India. According to the US Energy Information
Administration (EIA), India was the world’s third largest energy consumer as
per the data of 2013, after China and the United States of America. Although
India has a lot of fossil fuel resourses, there is a large dependency on the energy imports. In
2015,. This section deals with current amount of energy India is producing and
the sources vailable for the same.
(Source- US EIA)
Nearly 80% of total electricity
generated in India is from coal. As on 31.03.16, the
estimated reserves of coal were 308.80 billion tonnes, an addition of 2.20
billion tonnes over the last year. India was the
third top coal producer in 2015, according to the BP
Statistical Review of World Energy, June 2017.
The average quality of the Indian coal is not very
high and this necessitates the import of high quality coal to meet the
requirement of steel plants. Import of coal has steadily increased from 43.08
MTs during 2006-07 to 199.88 MTs during 2015-16.
A replacement for coal will not only reduce India’s
import dependency but also reduce dependency on an environment polluting source
of energy which is also non renewable in nature (prone to depletion)
There is high potential for generation of renewable
energy from various sources such as wind, solar, biomass, an hydropower. The
total potential for renewable power generation in the country as on 31.03.16 is
estimated at 1198856 MW. This includes wind power potential of 102788 MW
(8.57%) at 80m hub height, wind power potential of 302235 MW (25.21%) at 100 m
hub height, SHP (small-hydro power) potential of 19749 MW (1.65%), Biomass
power of 17,538 MW (1.46%), 5000 MW (0.42%) from bagassebased cogeneration in
sugar mills, 2556 MW (0.21%) from waste to energy and solar power potential of
748990 MW (62.48%).
The all India gross electricity generation from
utilities was 6,70,654 Giga Watt-Hours (GWh) during 2006-07. It rose to 11,67,584 GWh during 2015-16. The production of electricity from utilities
has increased from 11,16,850 GWh during
2014-15 to 11,67,584 GWh during 2015-16, registering an annual growth rate of
about 4.54%. Total Electricity
generation in the country, from utilities and non-utilities taken together
during 2015-16 was 13,35,956 GWh. Out of the total electricity generated
through utilities, 9,43,013 GWh was generated from thermal and 1,21,377 GWh was
from hydro and 37,414 GWh was generated from nuclear sources. Total output from
non-utilities was 1,68,372 GWh.
(Source-Indian energy statistics 2016, Bureau of
Energy Efficiency India, BP Statistical Review of World Energy, US Energy Information
Energy Crisis in India
Energy consumption in India is characterised by low
per capita level and a large disparity between urban and rural areas. Primary
energy consumption in India more than doubled between 1990 and 2013, reaching
an estimated 775 million tons of oil equivalent. India has the second-largest
population in the world, at nearly 1.3 billion people in 2014, growing about
1.4% each year since 2004, according to World Bank data. At the same time,
India’s per capita energy consumption is one-third of the global average,
according to the International Energy Agency (IEA), indicating room for higher
energy demand in the long term as the country continues its economic
Per capita electricity consumption (Values in KWh
per capita)- comparision
(source – The World Bank Data, IEA)
KWh consumed per capita
There have been severe electricity shortages in
India. Significant parts of the country, particularly in rural areas, do not
have access to electricity. The IEA estimates that overall household
electrification in India was 81%, representing 237 million people without
electricity, in 2013. Although 96% of urban households had electricity, only
74% of rural households had access, and often the rural consumers experienced
much more frequently interrupted electricity supply. This is due to insufficient
fuel supply and power generation and transmission capacity, disruptions in
domestic fuel supplies, and transmission and distribution losses and technical
problems in moving electricity between various states.
data, International Energy Agency, US Energy Information Aministration)
of renewable energy in India
Despite having large coal reserves and overall
growth in coal and natural gas production over the past two decades, India is
increasingly dependent on imported fossil fuels. India’s current administration
under Narendra Modi has a goal of reducing India’s import dependency on oil and
natural gas to two-thirds by 2022 and to half by 2030.
The energy we produce and import is still not enough
to meet the current needs of the country, keeping in mind the low per capita
consumption of electricity.To make India self sufficient in terms of energy
production and meet the need of growing population, India will have explore and
develope other sources of producing energy. With depleting fossil fuel reserves and concerns about its
environmental impact, renewable energy is the only long-term solution.
Renewable energy production has a high potential of the development in India
given its rich resources.
This is the share of current installed renewable
power capacity of India. The ministry of new and renewable energy has the
target of producing 175 GW renewable energy by 2022.
Renewable energy can re-energize
India’s economy by creating millions of new jobs, allowing the country to
achieve energy independence, reduce its import depenency.
Renewable energy has particular
relevance in remote and rural areas, where 74 percent off the people do not
have the access to reliable sources of energy. As we have seen that there
is insufficient fuel suppy and lack of good infrastructure for transmitting and
distributing this fuel, installing renewable energy plants right at the place
of use can be of great advantage.
Energy conserving technologies in Air conditioning systems
Solar hybrid HVAC
It increases the cooling system efficiency and reduces operating
expenses by replacing a percentage of mechanical energy required to power a
compressor (saving electricity) with modulated solar thermal energy.
The hot gas discharge line from the compressor is connected to the top
inlet of a Smart Solar Panel. Heat and pressure are added to the refrigerant,
generated by the sun and the heated/pressurized refrigerant is returned from
the panel outlet to the HVAC unit’s condenser. By adding heat/pressure to the
refrigerant by this method, compressor’s energy consumption can be reduced by
up to 40%.
This solar thermal system displaces a portion of the mechanical energy
used by variable capacity, multi-stage, and variable speed compressors, which
keeps the compressor in low stage, low range or low capacity, while delivering
full and part-load cooling requirements. This effect creates significant energy
Design of Solar Thermal Panel:
It is a patented computer-controlled parabolic concentrator which
produces more energy than any other panel of the same size. This technology has
solved two major issues with solar thermal panels: degradation and stagnation.
Solar Thermal Panels currently in use, cannot regulate the amount of heat being
added to the working fluid. When systems are not in use they can cause extreme
heat buildup and even damage the coatings of an evacuated tube panel. When
integrated with HVAC equipment this could cause severe damage to the refrigerant
which may cause the compressor to fail.
It includes a plurality of elongated parabolic reflectors mounted within
a glass-topped enclosure for pivotal movement such that each reflector is
incrementally pivoted throughout the course of a day to remain substantially
perpendicular to the sun. The incremental pivotal movement is caused by a motor
energized from a solar switch having solar cells that also pivot throughout the
day so that in one position of the switch, no electricity is being generated
and transferred to the motor, but in a second position, the switch receives
solar radiation and energizes the motor to again incrementally pivot each
reflector along with the solar switch. The reflectors are therefore
incrementally pivoted throughout the course of a day to follow the sun for
optimal collection of solar radiation which is used to heat liquid carried by
tubes positioned at the axis of generation of the parabolic reflectors and/or
strips of solar cell material so that electricity can be generated alone,
liquid heated alone, or liquid heated and electricity generated simultaneously.
For a 10 ton A/C which is equivalent to 12HP VRV, consuming 11 kWh of
electricity, for 25 working days, operating 10 hrs /day with 60% load.
Total monthly electricity charge =
Rs 0.6*10*25*11*9 = Rs 14850
average cost of electricity in urban India for commercial sector to be 9 Rs/kWh)
This Hybrid Thermal System saves 40% of energy consumption lowering
monthly charge by Rs 6000
Total Panel installed cost is about Rs1.75 lakhs which will thus be
recovered in 30 months (Rs 1.75 lakhs / Rs 6000 ? 29.167 months )
2) Ultraviolet Germicidal Irradiation
(UVGI) in HVAC systems
aim of using UVGI technology in HVAC industry is to improve the effiency of its
Air handling units (Coils) which leads to overall efficiency increase and saves
energy consumption of the unit.
technology of cleaning the heat exchanger coils with UV rays has been
improvised by Alfaa UV, by
developing, with the help of simulations and calculations, an efficient UVGI
system with optimum position and number of UV lamps and dosage, which has made
the technology accurate and ecconomical.
Biofilm on heat exchanger coils
Heat exchangers (evaporator and condensor) of an air
conditioning system use cooling coils which consists of copper tubes to which
aluminium fins are attached (to increase the air side surface area). The water
or refrigerant flowing through the tubes wets the coils surface causing
microorganism growth. A film of Pseudomonas
airuginosa is developed on the outer surface of coil, thus interacting with
the air flowing outside. This is known as the formation of biofilms on the heat exchanger coil.
Problems due to biofilm
are a source of biological contamintion. It deteroites the indoor air quality
(IAQ). The miroorganisms are also a source of diseases. Plus sticky films
attract dust particles.
biofilm covering decreases the free flow area. The causes the velocity of the
flowing air to increase. As the velocity head increases, the pressure head
drops, thus increasing the load on blowers (increased
films act as thermal insulation, reducing effciency of heat transfer between
the air and fluid across the coil (heat transfer coefficiant decreases).
the heat transfer coefficient decreases, chilled water flow rate increases,
causing lower water side temperature difference. As conditions are non-optimum,
more energy is consumed
Biofilm thickness (fins)
Energy usage increase
Cleaning of coils –using UV
methods of periodic cleaning of coils include pressure washing and chemical
cleaning. Both involve manpower and maintanance cost. These can also damage
sensitive parts and chemical can be dangerous for indoor occupants.
UVGI system – The installed UV lamps emit ultraviolet radiation which directly
attacts the microorganisms. It destroys the exsisting biofilm and also prevents
any future growth.
the system is installed, no periodic maintenance or manpower is required. As
the coils are always clean, the unit saves on a lot of electricity.
helps in saving
consumed in running the blowers
flow rate increase by 15%
consumption decrease by 10.2%
accumulation decrease by 97.2%
The better method
this technology of cleaning coil with UV rays is used in many HVAC systems
today, many users cannot decide optium number and position of the UV tubes to
less number of tubes and fixing them at incorrect locations will create “Dead
zones” on the coil surface where the exposure to UV rays is not enough.
Microorganisms which require high dosage will grow in these zones thus
defeating the purpose of the UV tube system.
more number of tubes than required is uneconomical and also can cause damage to
the UV parts inside.
UV uses a simulation software coupled with computational fluid dynamics. It can
calculate the exact dosage recieved by the microbes as they travel through the
air handing units. The simulation can calculate the exact UV irradiance at
every point of the coil surface. It highlights the area of low irradiance and
reports maximum and average irradiance across the coil surface. The report also
provides ideal mounting positions and distances for the tubes with respect to
powered vapour absorption system
In the case of conventional vapour compression
system, the compressor is the most energy consuming component. External work
has to be done on the compressor in order to increase the pressure and
temperature of the refrigerant. But in case of vapour absorption system, the
compressor is replaced by the absorber-generator unit. The absorbent use in the
absorber absorbs the refrigerant by releasing some amount of heat. This mixture
then passes through a heat exchanger to the generator. The generator is given a
heat supply. Absorbing this heat, the refrigerant, at high temperature and high
pressure, seperates out from the mixture. Thus we have achieved pressure
increase without a compressor.
Replacement of the compressor, which consumes high
grade eletrical energy with heat energy, which is low grade energy, makes the vapour absorption
system more favourable.
heating – using solar energy
The generator requires external heating. This
heating can be provided by electrical means or by burning or fossil fuels in a
furnace. As energy consumption is already been reduced by replacing the
compressor, by energy conservation can be implemented by using renewable source
of energy – Solar energy.
system uses a solar flat plate collector. Flat plate collector is an insulated box
containing a dark absorber plate under a transparent or a translucent cover. The
absorber plate is made up of copper as it has high thermal conductivity. Absorbing
efficiency is 97%. Moreover black paint is used over the copper plate which has
absorptance 0.85 to 0.9. Hence the plate ensures that maximum heat is tranfered
to the generator.
calculations, solar vapour absorption refrigeration system has a coefficient of performance (COP) about 0.69, the COP of the entire system is about
0.58. These values were calculated by
considering the capacity as 1TR. Using water at 25 degree Celsius as the condensing
medium and eveporator pressure as the atmospheric pressure, temperature and pressure
were calculated at every point and plotted on the ph curves. From the curves we
can know the values of enthalpy at every point.
we know that the refrigerting effect
is 1TR, mass flow rate of ammonia through the evaporator can be obtained using
(change in enthalpy) =1TR
the Mr, heat remove from the compressor is calculated and using enthalpy values
from the curve heat input to the generator can also be obtained.
(refrigerating effect) / (heat input in generator)
value of COP shows that this system is feasible and plus the use of solar energy
has reduce the electric load of the system.
Institute of technology, Kurukshetra has adapted this system in their premises.
As it is not a commercial organisation and the product is not yet floated by
any commercial organisation in market, the cost analysis of the product is not