BIO-GAS -A BOON FOR RURAL ELECTRIFICATION SYSTEM

The world today is behind two resources – energy and water. Over the years man has utilized positively or negatively various conventional resources to satisfy his needs and greed. Thus, limited storage of resources have been depleting steadily. Hence the propagation of non-conventional energy sources and their utilization is imperative today.

 

Why Bio-gas?

Bio gas generated from locally available waste material seems to be one of the answers to the energy problem in most rural areas of developing countries. Gas generation consumes about one fourth of the dung but available heat of gas is about 20% more than that of obtained by burning the entire amount of dung directly. This is mainly due to very high efficiency (60 %) of utilization compared to poor efficiency (11%) of burning dung cakes directly. The technology thus seeded and spawned is populist technology based on ‘Nature’s income and not on nature’s capital’ so being an agricultural country use of bio-gas as a fuel for cooking or lighting purpose can be the best solution for all Indian farmer families.

 

Potential for Bio-gas energy

The potential of renewable energy in India is estimated as 1,00,000 MW while for bio-gas and bio-mass it is 19,500 MW. So there is need to bring about change in mind to focus on renewable sources of energy. No matter whether you get the power from Thermal Power station , Hydro Power Plant or from Bio-gas Plant, the end product is energy and power.

 

Bio-gas technology – General Description

Bio-gas or gober-gas is clear, odorless combustible gas which is produced when organic matter content in animal excrements like dung, human night soil, parts of a tender plants or residues like leaves, stems and straws are anaerobically fermented with the help of methenological bacteria in air and water tight containers called bio-gas digester.

 

Chemically, a useful gas is just a methane gas. It’s chemical composition consist of one part of carbon (C) and four parts of Hydrogen molecule. It’s chemical formula is CH4 .Bio-gas burns with clear blue flame without giving any smoke. It’s flame temperature is up to 800 oC and it has calorific value of 5650 KCAL/ m3

 

Technical aspects

Bio-gas is a mixture of :

Methane (CH4 ) : 50 to 70 %

Carbon-dioxide (CO2) : 30 to 40 %

Hydrogen (H2 ) : 5 to 10 %

Nitrogen (N2 ) : 1 to 2 %

Hydrogen Sulphide (H2 S) : Small quantity

 

Bio-gas is generated when bacteria degrade biological material in absence of oxygen process known as anaerobic digestion. This process produces less temperature hence valuable in terms of energy conservation.

 

Advantages

One cubic meter of biogas is equivalent to –

3.47 Kg of wood

0.63 liter of kerosene oil

0.61 liter of diesel oil

1.5 Kg Of coal

1.25 KWh of electricity

0.45 Kg of LPG

13 Kg of fuel dung

0.5 Kg of butane.

 

 

It is non polluting

It gives cheap and easily available energy.

It uses waste like animal and human excreta and plant residues, which can otherwise create undesirable conditions. So it can give hygienic, clean and safe atmosphere around populated areas.

Its slurry could be used as a nutrient rich manure in farms and could tremendously improved agriculture production.

It can substitute firewood for cooking, heating, fuel and kerosene for lighting so saving in foreign currency normally spent in fuel and fertilizers.

 

Socially it can save a lot of time and labour in activities such as cleaning, washing and cooking, which they can use for other income generating /saving activities to care more for their children and to learn.Environmentally information technology can save wood and through that help to save vulnerable forest, soil, water and clean of the environment.

Market Potential for Renewable Energy Technologies in India

The potential for generating power from wind, small hydro, and biomass is estimated to be around 85,000 MW. Only about 11,500 MW has been exploited to date. It is growing at an annual rate of 15%. The major areas of investment are: wind energy, small hydro projects, waste-to-energy, biomass and alternative fuel.

 

Wind Energy

India’s wind power potential has been assessed at 45,000 MW. The current technical potential is estimated at about 13,000 MW, assuming 20% grid penetration, which would increase with the augmentation of grid capacity in potential states. States with high wind power potential are Tamil Nadu, Gujarat, Andhra Pradesh, Karnataka, Kerala, Madhya Pradesh and Maharashtra. About 11.3 billion units of electricity have been fed to various state grids from wind power projects. Almost 80% of the power thus generated has been used for captive consumption, and the rest sold to the grid or to a third party.

 

Small Hydro Power (SHP)

India has enormous economically exploitable and viable hydro potential amounting about 84,000 MW. The estimated potential for SHP is about 15,000 MW. MNRE has a database of 4,233 potential sites with an aggregate capacity of 10,324 MW for projects up to 25 MW. A remaining 5,000 MW is under examination. The states mentioned in table above have announced policies for private sector participation in the SHP.

 

Biomass

500 million tons of crop and plantation residues are produced every year, a large portion of which is either wasted, or used inefficiently. Conservative estimates indicate that even with the present utilisation pattern of these residues and by using only the surplus biomass materials, amounting to roughly 150 million tonnes, about 19,500 MW of distributed power – biomass power generation 16,000 MW and 3,500 bagasse based co-generation- could

be generated.

 

Energy Recovery from Waste

There exists a potential for generating an estimated 1700 MW of power from the urban and municipal wastes, and about 1000 MW from industrial wastes. The potential is likely to increase further with economic development.

 

Biogas

The estimated potential of household biogas plants based on animal waste is 12 million units. The estimated biogas production from these plants is over 3.5 million m3 per day, which is equivalent to a daily supply of about 2.2 million m3 natural gas.

 

Bio-Diesel

In India, the jathropha tree, which produces an oil-rich nonedible fruit, is gaining admirers in the biodiesel world. The tree is drought resistant and considered an optimal source of oil for biodiesel because its fruits bear oilrich seeds. The oil is so pure that it can be used for transportation fuel in diesel-powered vehicles and equipment without extensive refining. The Indian government is providing fiscal and technology inputs to promote Jathropha and Pongamia as high yielding energy crops, especially in arid lands which were unviable for other cropping. These crops are becoming the preferred choice for generation of biofuels as their seeds have high oil content and they also help in improving the overall green cover through reforestation of relatively barren land resources.

 

This competitively priced, green and replenishable fuel offers an opportunity to many Emerging Markets to conserve their fossil fuel and forex reserves while simultaneously promoting sustainable livelihoods across the value chain. As per the estimates released by the Planning Commission of India there is total fallow land of 7400 sq. km. available for such cultivation. This provides a theoretical potential of savings to the tune of USD 357 million in terms of replacement with bio-fuel from currently un-utilised land.

 

Electric Cars

One of the most promising Electric Vehicle (EV) manufacturers is the REVA Electric Car in Bangalore, which has more than 1,000 small electric sedans on the road in India and another 600 in the United Kingdom under the brand GoinGreen. The Electric car produced by REVA is a niche play for urban motorists and commuter, with a top speed of 40 mph and a range of only 48 miles on a charge. But with cities like London, Rome, Athens and other cities offering exemptions from their inner-city driving restrictions and “congestion charges” and free parking to clean-power vehicles and EVs, start-ups like REVA see a big opportunity. The REVA car uses eight 6-volt lead-acid batteries, but its range could expand as lithium-ion and other battery technologies advance.