Ashwani Kumar and Vijay Rani Kumar
Energy Plantation Demonstration Project Center
Department of Biotechnology Project
Department of Botany, University of Rajasthan,
Jaipur - 302004. India.
Phone: 00 91 141 654100 Fax: 00 91 141 565905
ABSTRACT : At the global level, according to recent estimates by FAO the annual tropical deforestation rate for the decade 1981 to 1990 was about 15.4 million ha (Mha). According to the latest data published in 1994 for the assessment period 1989-1991, the total area under forests is 64.01 Mha accounting for 19.5 percent of India's geographic area. There is rapid depletion of forest products and in order to provide alternative energy sources a change is needed in conventional forestry management system. The fact that nearly 90 percent of the worlds population will reside in developing countries by 2050 probably implies that biomass energy will be with us forever unless there are drastic changes in the world energy trading pattern. Two plants of the semi-arid region have shown great potential of bio-fuel production during the last 17 yrs. of our investigations and efforts are underway to undertake their large scale cultivation and improvement at two sites in semi-arid region of Rajasthan. They include Calotropis procera and Euphorbia antisyphilitica. Three to 7 fold increase in their latex contents has been obtained and their biomass production is under process of optimization using various growth promoting agents and nutrients. Details of the work shall be presented.
1.1 Arid and semi arid lands occupy one third of the earth's surface. Indian arid zone occupies an area of about 0.3 million sq. km. 90 percent of which about 2,70,000 sq. km. is confined to north west Indian covering most of Western Rajasthan, part of Gujarat and small portions of Punjab and Haryana. India with its vast expanse of wasteland unsuitable for agricultural production (nearly 180 million ha) could be considered for economically viable production of biofuels.
1.2 Tropical deforestation is currently a significant environment and development issue. At the global level, according to recent estimates by FAO the annual tropical deforestation rate for the decade 1981 to 1990 was about 15.4 million ha (Mha). According to the latest data published in 1994, for the assessment period 1989-1991, the total area under forests is 64.01 Mha accounting for 19.5 percent of India's geographic area.
1.3 Modern bioenergy technologies and biofuels are relatively benign from environmental view point and produce very little pollution if burned correctly and completely. The creation of new employment opportunities within the community and particularly in rural areas is one of the major social benefits from the exploitation of biomass for energy, industry and environment. Use of biomass for energy and industry allows a significant quantity of hydrocarbons to be consumed without increasing the CO2 content of the atmosphere and thus makes a positive contribution to the Greehouse effect and to the problems of "global change" as occurs in both industrialized and developing countries. Further
advantages from utilization of biomass include : liquid fuels produced from biomass contain no sulfur, thus avoiding SO2 emissions and also reducing emission of N0x. Improved agronomic practices well managed biomass plantations will also provide a basis for environmental improvement by helping to stabilize certain soils, avoiding desertification which is already occurring rapidly in tropical countries,
1.4 The specific research work carried out in the areas of biomass production and utilization in less fertile areas of the world will provide satisfactory answers to the double challenge of energy crisis and forest deforestation in the country in general and semi-arid and arid regions of Rajasthan in particular. The possibility of conversion of biomass into strategic liquid fuels and electricity will make it possible to supply part of the increasing demand for primary energy and thus reduce demand for crude petroleum imports which entail heavy expenditure on foreign exchange.
1.5 Already European countries mainly Italy, Germany and Austria are leading in Biodiesel production nearing 500,000 tons in 1997 out of which 2,50,000 tonnes was produced in France. (1) The production capacity of biodiesel in Germany was fully utilized in 1997, the sold quantity amounting to roughly 100,000 t. The technologies for producing bio-oil are evolving rapidly with improving process performance, larger yielding and better quality products. The present paper shall discuss problem and strategies for use of biomass in developing countries.
1.6 Biodiesel production :
A recent World Bank report concluded that "Energy policies will need to be as concerned about the supply and use of biofuels as they are about modern fuels (and) they must support ways to use biofuels more efficiently and in sustainable manner. Although there is significant volume of biodiesel already produced in Europe there are remaining risks slowing down the further expansion to the target set by the European Commission to reach 5% market share in transportation fuels by the year 2000".
These risks are insecurity in raw material supply and prices, doubts about adequate quality assurance and hesitance for a wider acceptance by the Diesel engine manufacturers, mission marketing strategies for targeting biodiesel differential advantages into specific market niches and last not least missing legal frame conditions similar to clean air act in the USA.
1.7 Biomass as potential resources :
Biomass resources are potentially the worlds largest and sustainable energy source a renewable resource comprising 220 billion oven dry tones (about 4500 EJ) of annual primary production. The annual bioenergy potential is about 2900 EJ though only 270 EJ could be considered available on sustainable basis and at competitive prices.
Most major energy scenarios recognize bioenergy as an important component in the future worlds energy. Projections indicate the biomass energy use to the range of 85 EJ to 215 EJ in 2025 compared to current global energy use of about 400 EJ of which 55 EJ are derived from biomass(2).
1.8 Need for new strategies :
At present there is hardly 0.4 percent forest below 25 cm rainfall zone and 1.3 percent above 30 cm rainfall zone. There is rapid depletion of forest products and in order to provide alternative energy sources a change is needed in conventional forestry management. There is a need to develop new strategies to raise plantations in wastelands and utilize unutilized plant species which are able to thrive well under such conditions.
1.9 The strategies for the developing countries.
The present paper presents the strategies for the semi-arid and arid regions of the world where wastelands could be utilized effectively for the development of Biofuels as renewable sources of energy and their use on sustainable basis.
2. MATERIAL AND METHODS :
2.1 The plants :
Out of 2,50,000 plants species only 10,000 or so have been exploited during the course of human civilization. A large number of hydrocarbon yielding plants are able to grow under semi arid and arid conditions and they also produce valuable hydrocarbons (upto 30 percent of dry matter) which could be converted in to petroleum like substances and are used as fossil fuel substitute.
2.2 Growth and yield :
During the last 22 years investigations have been carried out on the optimization of yield and production of hydrocarbons by such plants at the 50 ha Energy plantation demonstration project center. Their yield could be increased three fold making their commercial cultivation feasible. Several other countries are producing and selling biodiesel on commercial basis.
2.3 Agrotechnology :
Certain potential plants were selected and attempts were made to develop agrotechnology for their large scale cultivation (3,4,5). A 50 ha hioenergy plantation demonstration project center has been established in the campus of the University of Rajasthan to conduct the experiments on large scale cultivation of selected plants with the objective of developing optimal conditions for their growth and productivity, besides conserving the biodiversity. Detailed investigations were carried out on the process of wasteland colonization utilizing the i.) hydrocarbon yielding plants ii) high molecular weigh hydrocarbon yielding plants, iii) non edible oil yielding plants, iv) short rotation fast growing energy plants.
(I) Hydrocarbon yielding plants included :
1. Euphorbia lathyris Linn.
2. Euphorbia tirucalli Linn.
3. Euphorbia antisyphilitica Zucc.
4. Euphorbia caducifolia Haines
5. Euphorbia neeriifolia Linn.
6. Pedilanthus tithymalides Linn.
7. Calotropis procera (Ait.) R.Br.
8. Calotropis gigantes (Linn) R.Br.
II) High molecular weight hydrocarbon yielding plants :
1. Pathenium argentatum Linn.
III) Non edible oil yielding plants
Jatropha curcas L
Simmondsia chinenesis (Link) Schneid
IV) Short rotation energy plants
Cassia siamea Lam.
Acacia tortilis (Forsk) Hayne
3. RESULTS :
3.1 Considerable work has been carried out on these plants by several scholars from our group. Investigations on several plant species have been carried out at our center including Euphorbia lathyris : Euphorbia antisyphilitica ; Pedilanthus tithymaloides; Calotropis procera ; Euphoribia neeriifolia, E. caducifolia and Simmonsdia. (5). Among the different species studies best results were obtained with Calotropis procera and Euphorbia antisyphilitica.
In general these plants are easily propagated through cuttings. the optimum period for raising cuttings is June-July and March-April. Regarding environmental variations ,March to October period was best suitable for E. antisyphilitica because of linear increase in growth was recorded in this period. During these months, maximum sprouting was observed in Pedilanthus tithymaloides, E. antisyphilitica and E.tirucalli. However Calotropis procera remained dormant during the May June period by shedding its leaves and could be propagated during the monsoon season only.
3.3 Edaphic factors
Among different soil types sand was best for the growth of E. lathyris and P. tithymalodes while red loam soil was best for E.antisyphilitica. However for E.lathyris latex contents were maximum on sand gravel. Red soil was rich in nitrate, sodium, potassium and phosphorus pentaoxide. E.antisyphilitica plants were relatively tall in sandy soil and less branched as compared to red soil. Plants grown in red soil branched more instead of increasing much in height.
3.4 Nutritional factors :
Application of NPK singly or in various combinations improved growth of all the selected plants. In general NP combination gave better growth which was only slightly improved by the addition of K for E.tirucalli. When the best doses of NPK were applied in different combinations like NP, NK, KP and NPK the last combination gave best results in the form of biomass, latex yield, sugars and chlorophyll in E.lathyris, and P.tithymaloides.
3.5 Salinity stress ;
Salinity stress when applied in the form of irrigation water the lower concentrations of salinity improved plant growth of E. antisyphilitica, E lathyris. and P.tithymaloides.
3.6 Application of growth regulators :
In the present experiment spray of growth regulators resulted in enhanced fresh and dry weight production. Maximum plant height was observed in GA3, followed by CCC, NAA, 2, 4, 5-T and IAA. However biocrude synthesis occurred more in auxins, NAA and IAA in E. sntisyphilitica. Out of all the growth regulators employed on P. tithymaloides IAA supported maximum plant growth in terms of fresh weight and dry weight of aboveground and underground plant parts. 2, 4, 5-T showed minimum plant growth, besides certain nodular structures were observed on the stem of the plant treated with 2,4,5-T. Biocrude yield was best in IAA followed by 2,4,5-T, GA3, CCC, NAA and control. Application of growth regulators on P. tithymaloides resulted in slight decrease in chlorophyll over the control plants. whereas on E. lathyris they induced favourable results, regarding chlorophyll. In E. lathyris IBA caused maximum fresh weight productivity followed by IAA, GA3 and NAA. NAA sprayed plants exhibited more production of hexane extractable. Favourable influence of growth regulators was also observed in sugar yield maximum being in NAA followed by IBA GA3 and IAA.
3.7 Micropropagation ;
Plant tissue culture has been successfully employed to achieve rapid clonal propagation of E. lathyris; Pedilanthus tithymaloides and E. antisyphilitica. Likewise propagation of jojoba has also been carried out.
4. CONCLUSIONS :
4.1 European commission EU has suggested alternatives to conventional hydrocarbon fuels such as methanol, ethanol, compresses natural gas (CNG), hydrogen vegetable oils and esterified vegetable oils. EU has presented a proposal in the framework EU's ALTERNER program for the promotion of alternative fuels. Within this program the EU has the objective of securing a five percent market share of total motor fuel consumption for biofuels of which it is expected that biodiesel will form the major share. EU draft specifications for vegetable oil Methylester Diesel fuel (Biodiesel fuel) have been suggested. Some countries notably Autria and Italy have already produced their own specifications for vegetable oil methylester diesel fuel. Total production in Europe could reach 200,000 tons by 1995. Rapeseed methylester diesel fuels are already sold in Italy but can only be marketed outside retail outlets. A Government decree fixes a maximum of 1,25,000 tones per year to be exempted from gas oil excise tax chain claiming tax exemption producers have to show that at least 80 percent of the raw vegetable oil used derives from "set aside" crops.
4.2 However for developing countries it is important to develop crop plants that grow on wastelands and are able to produce sufficient biocrude at economic costs. The present papers presented the details for strategy for wastland colonization using hydrocarbon yielding plants which could be employed for several developing countries (6).
Acknowledgement : The financial support received from Department of Biotechnology, Govt. of India, is gratefully acknowledged.
(1) F. Statt, Development of biodiesel activity France, Biomass for energy and Industry. Eds. Kopetz H. et al. 1998, 112-115.
(2) D.O. Hall and F.Rosillo-Calle. The role of bioenergy in developing countries. Biomass for energy and industry. Eds. Kpetz et al. 1998, 52-55.
(3) A. Kumar, Laticifers as potential bioremedients for wasteland restoration. J. Environment and Pollution 1994 1 : 101-104.
(4) A. Kumar and S. Ro[y, Biomass resources of semi-arid regions : Production and improvement of wood energy sources. Biomass for energy and environment. Eds Chartier, P. et. 1996, 721-724.
(5) A. Kumar, S. Johari and S.Roy, Production and improvement of bioenergy sources., J. Indian Bot. Soc. 74A: 233-244. 1994
(6) A.Kumar, Biomass energy crops of semi-arid regions of India and their energy potential. Biomass for energy and Industry. Eds. Kopetz, H. et al. 345-348. 1998