dawn 12 may 2007
In a country faced with a shortage of viable energy sources, bio-
diesel can be a “knight in shining armour” when it comes to meeting
fuel needs, writes Abdul Waheed Bhutto
THE government of Pakistan has launched a trial E10 gasoline pilot
project in the form of petrol blended with 10 per cent ethanol in
Islamabad and Karachi. Ethanol costs Rs20 per litre against the ex-
refinery price of Rs29 for petrol. From q consumer point of view,
the heating values of 1.38 litres of ethanol is equivalent to one
litre of petrol. Therefore, the per unit cost of ethanol was
inflated by a 27.5 per cent to arrive at cost for ethanol in terms
of equivalent energy released.
In Pakistan, both fuels are treaded on the volume basis. The
government has lowered the price of E10 gasoline by Rs1.50 per
litre. Nevertheless, the calculation shows that the government is
not providing any subsidy on E10 gasoline instead they are paying
same taxes which petro-gasoline customers are paying.
The promotion of E10 gasoline is likely to benefit the country’s
sugar sector if the benefits are also transferred to a farmer who
would like to grow more sugar cane for getting a better return. Such
a thing rarely happens in Pakistan. Nevertheless, there is a
powerful lobby of sugar mill owners that tries to influence the
government to implement E10 gasoline while more powerful refineries
and Oil Marketing Companies (OMCs) are resisting all such moves.
In Pakistan, ethanol is produced from molasses a by-product of the
sugar industry. Presently, around 16 distilleries are operating in
the country on 60 per cent of their capacity to convert on average
1.8 million tonnes of molasses. Around one tonne of alcohol is
produced from five tonnes of molasses.
The country has earned around $100.6 million on export of 167,610
tonnes in 2006 and $11.5 million on export of 22,975 tonnes in first
two months of current year. The average price fetched by exporters
for different grades of alcohol ranged in $560 to $680 per tonnes.
The value-addition in molasses through its conversion into alcohol
has enabled country to earn eight to 10 times more foreign exchange.
Oil marketing companies (OMCs) and refinery operators are resisting
the government’s decision of blending ethanol with petrol on the
grounds that petrol was currently surplus in Pakistan. According to
the Ministry of Petroleum and Natural Resources, 1.3 million tonnes
of surplus naphtha/motor gasoline was available for exports during
2005-06.
The blending of ethanol with petrol would mean that refineries will
have to export even more naphtha. They have also pointed out that
due to the hygroscopic nature of ethanol, it must be blended closest
to the retail outlets that required all the OMCs to invest Rs250
million in developing storage and blending facilities. However, the
above amount is not significant in considering the volume of their
business.
Both Naphtha and ethanol are primarily feedstock in chemical and
petrochemical industries. Unfortunately, this sector has not
developed in country as a result the local demand of both these
products is very small.
The fuel consumption trend suggests more focusing on promoting bio
diesel in the country because country has imported about 4.2 million
tonnes of diesel oil at a cost of around $1.7 billion during 2004-
05. Diesel dominates over 75 per cent of the market, with only 38
per cent supplies from the local refineries. In addition, diesel
vehicles of the technology used emit much more pollutant than petrol
vehicles.
Bio diesel is the clean burning alternative fuel for the diesel
engines which are produced from domestic, renewable resources. This
fuel is obtained from vegetable oils like soybean, rapeseed or
sunflower, through a process of transesterification , which changes
the properties of oil significantly. The additional chemical process
removes the glycerine from the oil to meet engine specifications.
Pure bio diesel can be used in unmodified diesel engines, and
blending offers the best commercial potential because of better
performance and lower costs up to now. Bio diesel can be mixed with
diesel in proportions of up to about 30 per cent and used in a
diesel engine without any modifications — for higher proportions of
blending and for pure bio diesel, no modification is necessary for
tractors but reasonable modifications of the engine are required for
conventional cars.
The viscosity and density of bio-diesel is similar to those of the
diesel. On the other hand, it is a better lubricant. As compared to
the petroleum-based diesel, bio diesel has a more favourable
combustion emission profile, such as low emissions of carbon
monoxide, particulate matter and unburnt hydrocarbons. The carbon
dioxide produced by combustion is recycled by photosynthesis,
thereby minimising the impact of bio diesel combustion on the
environment.
Another advantage of bio diesel is that it contains much lower
levels of sulphur in comparison to petroleum diesel. The sulphur in
petroleum diesel is corrosive to engines and when emitted, leads to
the formation of acid rain and forms particulates that can cause
health problems when they are inhaled.
Palm oil is certainly one of the most productive crops for bio
diesel. However, this production is deeply related to climatic
conditions (rainfall) and the quality of the soil. The vast
potential of bio-diesel from oil biomass is under investigation in
several countries.
In Europe, where approximately 34 per cent of cars have diesel
engines, bio diesel is widely available, even for use in passenger
cars. There are 1,000 filling stations which sell canola oil-based
bio diesel in Germany alone. The cost of the blend is approximately
the same as for the conventional diesel sold at that location.
Canola is the most abundant oilseed grown in Canada, whereas soybean
oil is the primary feedstock for bio diesel production in the US. In
Europe, efforts are being made to breed higher oil content plants
belonging to the Brassica family as dedicated bio diesel feedstock.
India aims at 20 per cent bio-diesel blending by 2011 and the Indian
government has identified 100 million acres of land across the
country for growing Jatropha. Brazil also launched its national bio
diesel programme in December 2004. Developing countries see bio
fuels as a way to stimulate agricultural development, create jobs
and save foreign exchange.
The cost of seeds represents 60 to 80 per cent of the total cost of
bio diesel production. The seed production costs vary widely
depending on where the crop is grown: quality of soils and seeds,
climate, quantity and prices of fertilisers and pesticides, etc.,
are all elements that affect yields and production costs. The
processing technology for producing bio diesel is presently oil
extraction followed by transesterification , both well-proven
processes with limited scope for significant cost reduction. For
this production pathway, the greatest potential cost reduction lies
in producing, harvesting, and transporting feedstock to processing
plants.
The major oilseed crops grown in Pakistan include cottonseed
rapeseed/mustard, sunflower and canola, etc. During the first nine
month of 2005-06, the local production of edible oil was estimated
at 0.809 million tonnes while during the same period, 1.269 million
tonnes of edible oil was imported and 0.216 million tonnes of edible
oil was recovered from imported oilseeds. Therefore, the prospect
using locally grown oilseed as feedstock for bio diesel in the near
future is very remote.
Nevertheless, most of the promising ingredients for bio fuels in the
country is an ordinary shrub Jatropha which is locally known as
Ratanjot. The Jatropha curcus resembles castors. The shrub produces
a seed that contains high oil content and can be used to blend with
diesel. They do not compete with food crops.
Jatropha does not require much water and can be raised in arid, semi-
desert areas as well. Farmers can get an average yield of over
1,000kg per hectare under rain-fed conditions. Jatropha is drought-
resistant and can be raised successfully even in areas where the
annual rainfall is between 300mm to 500mm.
Higher oil content plants belonging to the Brassica family has also
potential to be grown as dedicated bio diesel feedstock. Fats and
oils that are unsuitable for human consumption could also be
converted to bio diesel. The production cost can be minimised by
using restaurant waste oils and rendered animal fats that could also
help to resolve the dangerous problem of recycling.
When derived from a renewable domestic resource, bio diesel surely
reduces reliance on import. Our country has vast potential to grow
feedstock for bio diesel especially in the remote areas. Development
in this sector will also increase agricultural revenue and create
jobs, especially in the rural areas.
The writer is an assistant professor at the Dawood College of
Engineering and Technology, Karachi