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PV micro-grid – design features Biogas cooking grid – key aspects
PV micro-grid – design featuresBiogas cooking grid – key aspects
Design considerations for off-grid system –Estimated Load
Load Users No Watt
Domestic
Home - Light, 5 W 45 3 5
Home - Light, 3 W 45 2 3
Home - Mobile charger 45 2 3
Home - TV 15 1 60
Home - mixer 20 1 500
School Light 1 3 3
Community
Control room Light 1 1 5
Control room Fan 1 1 40
Street Light 1 7 12
Commercial
Pump 1 1 1500
Flour Mill 1 1 2250
Design considerations for off-grid system – Load profile
Productive applications are during the peak sun-shine hours
Design considerations for off-grid system – Seasonal variations in load profile
Design considerations for off-grid system
• Solar radiation
• Module specifications
• Peak demand
• Paying capacity of consumers
• Estimation of increase in demand
Mini grid case study
• Mini grid installed in village Darewadi of Pune district in Maharashtra
• 9.36 kWp solar PV system, 39 modules of 240 Wp, Bosch make
• 10 kW solar inverter, 48 V, 600 AH battery size
• 17 no. of poles for power distribution
• Domestic load: 3 LED lights per house, mobile charging and 8 TV sets till date
• Community load: 10 street lights, 2 computers; computers purchased by the trust
• Commercial load: One flour mill; purchased by the trust, 2 Submersible pumps fordomestic as well as irrigation purpose
Mini grid case study - Block diagram
Biogas cooking grid
Domestic fuel consumption in India
• Fuels used for cooking all over India
are LPG, kerosene, fire wood, crop
residue, cow dung cake and coal
• According to India’s census 2011
data, fire wood is predominantly
used as a cooking fuel in the
households especially in rural parts
• Out of 168 million rural households,
63% use firewood,
11% use LPG,
24% use crop residues, cow dung
cakes and coal,
1% use kerosene,
1% use biogas or electricity
0
20
40
60
80
100
120
140
Fire wood LPG / PNG Crop residue/ Cow dungcake / Coal
Kerosene Other(Biogas /
Electricity)
Total HH (million) Rural HH (million) Urban HH (million)
Challenges with fire wood and traditional methods of cooking
Firewood is collected by villagers either
from their own plantations or from
government forests, results in
deforestation
Gathering fire wood involves a lot of hard
work in walking long distances and
carrying head loads. These efforts are
carried out mostly by women and girls in
the villages
The women and children suffer
respiratory diseases, which is an obvious
impact of using fire wood and traditional
methods of cooking.
Challenges with LPG
People normally travel to taluka place to
get the LPG cylinder; hence the landed
cost of cylinder increases
LPG may not be the sustainable solution
for cooking in all parts of rural areas
because of price hike, challenges to get it
etc.
Typical reasons why villagers are not
willing to entirely switch over to modern
energy sources like LPG are either the fuel
is very expensive or it is not available
easily
Biogas as a cooking fuel
According to census 2011 data, 1.8 million
rural households are preliminarily using
biogas as a cooking fuel
The plants which were well constructed
and well maintained are running
satisfactorily
The key reasons why individual biogas
plant’s success rate is very low are either
the plants are not well constructed or no
mechanism for maintenance of the plant
or the cattle population of individual
drops down because of various reasons
Community biogas plant and biogas grid
One approach is to set up community biogas plant and biogas grid
This removes the uncertainties associated with individual biogas plants
Community biogas plant and biogas grid
• The tariff structure can be set to make the project viable economically
• There is the possibility of paying back the capital cost over a long term period
• Financial structuring needs to be explored in greater detail with all stakeholders having a role
• A few pilots are underway and will provide critical technical and social data
The outline
Conclusions
• Community biogas plant and biogas grid appears as sustainable solutions to cater to the village cooking energy needs
• In addition to availability of raw material (cattle dung) for biogas plant, willingness and commitment of villagers is key to success
• The revenue from gas and slurry can make projects viable
• There are obvious health, safety and environmental benefits
• Financing of these projects will need long term capital at favourable terms
• A few pilots are currently in various stages of development
