ELECTRIC GENERATING WITH BIOGAS

CASE STUDY
For the last few years , we have focussed on the Gaushalas & Panjrapoles where for Biogas based captive power generation projects in decentralised manner. The dung potential is generally avaialable ( which otherwise would be used as fertiliser) in gaushala /panjrapole to go for Bio-gas plants . The produced gas is used to generate the electricity running the DG sets on dual fuel mode by the beneficiary . The digested slurry coming out of the plant is used for organic fertiliser production.

One such demonstration project has been commisioned in Nov’97 & has been working satisfactory at Shri Idar Panjrapole Sanstha – Idar. A brief note on the same is enclosed .

Potential :

Our State has enriched livestock population of about 18.3 million . This animal wealth produces about 37 million kgs animal dung , which has potential of producing about 1.2 milion cubic meter bio-gas . This huge amount can suffice the cooking fuel requirement of about 50 lacs families.

Power generation Potential :

Considering 0.6 m3 biogas /kwh electricity generation through dual fuel diesel generating sets , approximately total 12 lacs families may be facilitated by electricity supply for 4 hrs/day.

Technology Options :

Our Gujarat state has one advantage of very moderate seasonal tempreture variation i.e. unlike , Nothern belt region tempreture difference is varying between 25 to 45 degree centigrade which is favorable factor for bio-gas generation . Looking to our village flora & fauna , Standard floating dome plants ( KVIC 40 days – HRT , vertical model ) may be adopted for setting up decentralised/ captive utilisation based electricity generation projects.

Plant Capacities :

The plants of 15, 25, 35,45,60,85 m3/day capacity may be taken up for implementaion for bio-gas generation in modular fashion for meeting cooking fuel requirement on daily basis. However , having electricity generation as main objective, the plant capacities of 45 & above are preferred. One project on Bio-gas based electricity generation by using dual fuel Generator Set was installed at Idar Panjrapole Sanstha.. Two more project are under progress in Rajkot & Bhuj Districts.

Panjrapole Sanstha.. Two more project are under progress in Rajkot & Bhuj Districts.

Conceptual Detailing is tabulated below.


Sr. No. Plant capacity
(m3/day) Cattle population required Dung required on daily basis Possible size of DG set to be coupled with biogas plant Approx. DG running per day & Total unit generation / day
1 15 25 -30 225 kgs 3.5 kva /3.0 kw
( single phase genset)
4 -5 hrs/day
( 12 to 15 units /day)

2 25 62 -70 625 kgs 3.5 kva /3.0 kw
( single phase genset)
7 -8 hrs/day
( 20 - 24 units/ day )

3 35 85 - 95 875 kgs 7.5 kva /6.0 kw
( Three phase genset)
5- 6 hrs/day
( 30 - 36 units / day )

4 45 120 - 130 1130 kgs 7.5 kva /6.0 kw
( Three phase genset)
7 -8 hrs/day
( 45- 50 units /day )

5 60 150 - 160 1500 kgs 10 kva /8.0 kw
( Three phase genset)
9 -10 hrs/day
( 80 –90 units/day )

6 85 220 – 250 2125 kgs 10 kva /8.0 kw
( Three phase genset)
13 -14 hrs/day
(120-130
units/day )
The above data has been computed based on the consumption of biogas @ 15cft bhp)

In case if no of hrs of electricity are to be increased OR higher capacity gensets are to be run , accordingly the plant capacity may be increased by installation of additional unit provided sufficient cow dung is available.


The cost of DG set has not been taken into account , however if bio-gas is not to be used as cooking fuel & electricity is to be generated , cost of 85CMD plant (including DG set cost , other auxiliary equipment / modifications etc.) appears to be around Rs. 10 lacs approximately.