Energy analysis and options of Indian agriculture

Agriculture accounts for most of the energy consumed in India. Non-commercial sources may be insufficient for food production. Substitutes or alternatives have to be developed for some agricultural products. It is feasible to produce cheaper acceptable substitutes for sugar (from crop residues), milk (from corn), animal feeds (from waste recycling), etc. Physical inputs and outputs transformed to energy were used to evaluate energy utilization in agriculture. Major inputs were farmyard manure (FYM), irrigation, bullocks, and farm equipment. Inputs were computed from the stage of primary fuels. Tubewell irrigation consumed 9.4 GJ/ha and accounted for 6.8% of the energy output of sorghum fodder, 13.9% of berseem, 15.2% of wheat grain, 15.9% of sugar, and 37.0% of rice. Inputs were 249–324 MJ/cm-ha in different crops. Fully utilized, the minimum energy inputs through equipment for one hectare of wheat would be 9.2 GJ on bullock-operated farms and 5.9 GJ on tractor-operated farms. Actually, because of small farm sizes, use is 29.2 GJ on bullock-powered farms and 8.3 GJ on farms with tractors. Costs of wheat production are about 40% higher on bullock-operated farms. Pest and weed control account for less than 2% of the energy inputs of crops. Energy returns as grain are 99% for wheat, 76–90% for rice, 17–28% for corn, and 52% for planted sugar and 103% in ratooned sugar cane. An annual crop rotation of paddy and wheat in Haryana consumed less energy and yields more energy (edible and as biomass) than sugar cane.Rural fuel supplies being marginal, dung is preferentially used as fuel and hardly 10% of the recommended levels of FYM are applied. Energy utilization from dung as fuel is double that as fertilizer replacement. Biogas will not be the fuel of the poor and will force them to fell vegetation for cooking fuel. Solar cookers are promising alternatives. Considering the extensive needs for low (or no) cost cooking fuel, we conclude that the Indian energy economy (and agriculture) will improve by using more fertilizers (and less FYM) and farm machinery (with reduced dependence on bullocks). Farm residues and other biomass may be processed to augment supplies of domestic and industrial fuels.     

Energy audit of farm equipment

Total energy inputs in machinery and other farm equipment are assessed. Included are fixed energy costs of crop production on small, medium, and large canal-irrigated farms. The operational energy costs of growing a ha of wheat crop on farms of different sizes have also been computed. The total fixed energy inputs per cropped ha on a small farm are about 4.5 million kcal; about 1.9 million kcal are required on medium-sized farms and 1.2 million kcal on large farms. The total energy costs for using farm equipment for 1 ha of wheat crop are 4.8, 2.2, and 2.4 million kcal on small, medium, and large farms, respectively. Medium-sized farms are now the most energy-efficient; by replacing bullocks by tractors and related equipment, large farms will become most efficient.     

Variation in energy consumption in production of wheat–maize with varying altitudes in hilly regions of Himachal Pradesh, India

Availability and consumption pattern of energy and constraints in its proper supply and management for crop production was studied in wheat–maize cropping system in selected hilly rural villages located at different altitudes of Himachal Pradesh in Western Himalayas. The information was collected from 90 farmers drawn from nine villages, three each from three selected altitudes using two-stage random sampling. The average values of energy consumption for wheat crop in low and high hills were, respectively, 41.68 and 110.8 MJ/ha and those for maize crop were, respectively, 43.43 and 81.33 MJ/ha. The productivity of wheat crop ranged from 1077 to 1840.9 kg/ha and for maize crop from 1108 to 1573 kg/ha, in low and high hills, respectively. The major constraints in the proper use of energy in crop production were the uncertain supply of different inputs due to difficult and undulating terrain, poor land holdings and non-availability of suitable technologies. The introduction of small powered equipment, precise use of seed and fertilizer and proper management of irrigation water were recommended for efficient energy use and better crop productivity.     

Determination and modelling of energy consumption in wheat production using neural networks: “A case study in Canterbury province, New Zealand”

This study was conducted on irrigated and dryland wheat fields in Canterbury in the 2007-2008 harvest year based on an extensive process of data collection involving a questionnaire and interviews. Total energy consumption in wheat production was estimated at 22,566 MJ/ha. On average, fertilizer and electricity were used more than other energy sources, at around 10,654 (47%) and 4870 (22%) MJ/ha, respectively. The energy consumption for wheat production in irrigated and dryland farming systems was estimated at 25,600 and 17,458 MJ/ha, respectively.In this study, several direct and indirect factors have been identified to create an artificial neural networks (ANN) model to predict energy use in wheat production. The final model can predict energy consumption based on farm conditions (size of crop area), farmers’ social considerations (level of education), and energy inputs (N and P use and irrigation frequency), and it predicts energy use in Canterbury arable farms with an error margin of ±12% (±2900 MJ/ha). Furthermore, comparison between the ANN model and a Multiple Linear Regression (MLR) model showed that the ANN model can predict energy consumption relatively better than the MLR multiple model on the selected training set and validation set.     

Energy balance and energy economic analyses of rice production systems in Ayeyarwaddy Region of Myanmar

The status of energy balance and energy economics of irrigated and rain-fed rice production systems is studied and compared for highlighting the effect of farm size. Primary data were collected from 51 irrigated and 54 rain-fed rice farms in Northern Ayeyarwaddy Region, Myanmar. Farm classes were identified as small (<2.5 ha) and large (2.5–25 ha). Energy estimates were calculated from actual amount of inputs and outputs and corresponding conversion factors. Results showed that the total energy inputs were 19,170.5 and 11,031.1 MJ/ha, respectively, in irrigated and rain-fed rice systems, while the total energy outputs were 104,162.7 and 65,033.5 MJ/ha in the two systems, respectively. Energy efficiency ratios, defined as output-to-input energy values, were 5.6 and 5.9 in irrigated and rain-fed rice production systems. Interestingly, the two systems were not statistically different for their energy efficiencies. Similarly, the energy efficiency ratios for different farm classes under both rice production systems were also not statistically different. Energy productivity and specific energy were 0.27 and 3.8 kg/MJ; 0.29 and 3.9 MJ/kg in irrigated and rain-fed systems, respectively. The energy benefit–cost ratio was higher in rain-fed rice (1.1) than in irrigated rice (0.9) system. Rain-fed system seems to have potential of further increasing yield through the increased yet appropriate use of energy inputs.     

Energy utilization in maize production

Average physical inputs in maize cultivation in three districts of Haryana (North India) have been transformed into energy units and compared with the energy outputs of grain and byproducts. The chief inputs were in the form of farm yard manure (FYM), traditional farm equipment, tractor and fuel, followed by irrigation and chemical fertilizers. Detailed data of physical inputs were collected from 31 individual farm units of Ambala district, ranging from 0.41 to 3.24 ha. Six of these farms showed extremes of size, tractor use, fertilizer application, FYM inputs, irrigation, as well as yields of grain and byproducts. Data from these farms were analysed in terms of energy utilization. Energy use efficiency ranged from 0.06 to 0.28 for grain and from 0.29 to 1.16 for total produce. The data suggest that grain production can be increased and energy utilization improved by minimizing the use of FYM and by increased use of chemical fertilizers and irrigation.     

Energy input and yield relations for wheat in different agro-climatic zones of the Punjab

Modern farming has become very energy intensive. Nowadays cropping pattern, farm activities and level of technology define the energy requirements. Energy needs are not only increasing in the agricultural sector, but in all sectors involving human activities. There is a great need to balance the use and availability of energy especially in the agricultural sector, in such a manner, so as not to affect the production adversely. Realising the implications of energy use, a study was carried out on the energy consumption patterns, in different agro-climatic zones, for the wheat crop in the state of Punjab in India. Mathematical relations were fitted to the yield and total energy input. An attempt was also made to optimise the energy inputs using a frontier production function for different agro-climatic zones. Under the present conditions, where irrigation is not assured, there is not much scope for increasing the yield of wheat in zone 1. However a 5.4% increase in yield is expected in zone 2 by providing 26.9% additional energy input through irrigation and the use of a fertiliser. The yield can be increased by 3.2% to 4049 kg/ha from 3922 kg/ha by putting 18.6% more energy input in zone 3. Yield can be increased to 4934 kg/ha (an increase of 13.7%) by an additional energy input of 28.5% in zone 4. On the other hand, the additional energy input of 29.6% gives only 1.3% increase in yield in zone 5. In most cases, the proper placements of seed, irrigation and fertiliser played significant roles in increasing the productivity in addition to some unknown parameters such as soil type and weather conditions.     

An investigation into the energy use in relation to yield of traditional crops in central Himalaya, India

Agrobiodiversity and agroecosystem management have changed in central Himalaya due to increasing emphasis on market economy and the motive ‘maximization of profit’. Such changes have benefited local people in economic terms, but at the same time increased their vulnerability to environmental and economic risks. The present study addressed the issue of how the ecological functions that are provided by agrobiodiversity translate into tangible benefits for the society. Important characteristics of agrodiversity management are the use of bullocks for draught power, human energy as labour, crop residues as animal feed and animal waste mixed with forest litter as organic input to restore soil fertility levels. The present analysis of resource input-output energy currency in traditional crop production indicated that inputs into different crop systems were significantly higher during kharif season compared to rabi season both under rainfed and irrigated conditions. The maximum input for crop during rabi season (second crop season) was about 31% of that of kharif season (first crop season after fallow) under rainfed conditions. Under irrigated conditions the rabi season input was about 63% of kharif season input. Under rainfed conditions, paddy sole cropping required maximum inputs (231.31 GJ/ha) as compared to mustard sole cropping (11.79 GJ/ha). The present investigation revealed that the total energy inputs and outputs are higher for irrigated agriculture as compared to rainfed system, the difference in inputs is about 5 fold and outputs is about 2 fold. The output-input ratio showed that irrigated systems have higher values as compared to rainfed systems.     

Comparison of renewable fuels based on their land use using energy densities

In this article energy densities of selected renewable fuels are determined. Energy density is defined here as the annual energy production per hectare, taking energy inputs into account. Using 5 scenarios, consisting of 1 set focusing on technical differences and 1 set focusing on geographical variations, the range of energy densities currently obtained in Europe was determined for the following fuels: biodiesel from rapeseed; bioethanol from sugar beet; electricity from wood, wind and solar PV.The energy densities of the fuels produced from biomass were calculated by determining the energy contained in the energy carrier produced from the crop annually produced on 1 ha, from which the energy inputs for crop cultivation and conversion were subtracted. For wind and solar electricity, the energy density calculation was based on the energy production per turbine or cell and the number of turbines or cells per hectare after which the manufacturing energy was subtracted.Comparing the results shows that, for the average energy density scenarios, the ratio between the energy densities for wind, solar, and biomass is approximately 100:42:1, with wind electricity also having the highest energy output/input ratio.A case study was done in which the energy density was used to calculate the distance a vehicle can cover using the energy carrier annually produced per hectare. This was done for 3 regions, in Mid-Sweden, North-Netherlands, and South-East Spain. The results of the case show that wind electricity results in the largest distance covered, except in Spain, where solar electricity is the most favourable option.     

Energy auditing of diversified rice–wheat cropping systems in Indo-gangetic plains

The field investigations were carried out for energy use analysis in terms of different input requirements and outputs harvested under the diversified rice–wheat cropping systems at the research farm of Project Directorate for Cropping Systems Research, Modipuram, Meerut, India during the year 2000–2004. The experiments were conducted on rice (Oryza sativa L.)–wheat (Triticum aestivum L. emend. Fiori and Paol) system involving 8 sequences using diversification, furrow irrigated raised bed system (FIRB) of sowing wheat, use of summer period for deep ploughing or raising legume crops for seed or green manure to study the energy dynamics of different diversified cropping systems. Results revealed that total energy use was highest in rice–potato–wheat (i.e. 77,601 MJ/ha in flat bed & 75,697 MJ/ha in raised bed) followed by rice–wheat–sesbania (i.e. 48,770 MJ/ha in flat & 47,830 MJ/ha in raised bed) and rice–wheat–greengram (i.e. 48,414 MJ/ha in flat & 47,482 MJ/ha in raised bed). In overall, the raised bed sowing of wheat in the cropping system consumed 6–11% less fertilizer energy than flat bed while saved up to 4.2% energy through irrigation. The total output energy of the system was recorded significantly higher in rice–potato–wheat system (i.e. 222,836 MJ/ha in flat bed & 218,065 MJ/ha in raised bed) in comparison to rice–wheat–greengram (i.e. 177,477 MJ/ha in flat bed & 175,125 MJ/ha in raised bed), rice–wheat–sesbania (i.e. 172,000 MJ/ha in flat bed & 168,919 MJ/ha in raised bed) and rice–wheat system (i.e. 156,085 MJ/ha in flat bed & 151,862 MJ/ha in raised bed). The significantly higher net return of energy was obtained in rice–potato–wheat system as compared to other systems. This system required about 75% more input energy but provided about 42% more output energy compared to conventional rice–wheat system. About 10% higher output energy was obtained through growing greengram in summer for grain and foliage incorporation while 14% gain obtained by green manuring sesbania, when compared to deep summer ploughing after wheat harvest.     

Fertilizer use saves fuels in India

Dung supplies are inadequate to provide enough farmyard manure (FYM) and cheap dung-cakes. Use of FYM necessitates supply of other fuels for cooking. Fertilizers consume only 5% of the thermal energy embodied in FYM. Replacement of the currently used amount of FYM by fertilizers will save fuels and costs. If all of the plant nutrients are to be supplied by FYM to a hectare of wheat crop, 2.9 tonnes of coal are needed to replace the dung-cakes lost; fertilizer use will save Rs. 1444/ha. It is suggested that FYM use be minimized and fertilizer use increased for fuel thrift.     

Energy consumption pattern of wheat production in India

Wheat covers approximately 25% of the total global area devoted to by cereal crops. Wheat production needs to be augmented to meet the growing demand. The amount of wheat produced is a direct function of energy inputs. Wheat is produced using energy sources ranging from human and animal power to power of heavy machinery. The basic purpose of the present study is to optimize energy use patterns of different wheat growing regions (Western Rajasthan, Punjab, Uttar Pradesh (UP) and Madhya Pradesh (MP)) of the Country in order to maximize yield. Villages and farmers were randomly selected for collecting data on energy requirement of wheat in Western Rajasthan and data for other regions were taken from reports. Wheat consumed maximum energy input in Western Rajasthan because light textured soil required frequent irrigation. Punjab and UP recorded maximum output–input energy ratio, 5.2 and 4.2, respectively. Punjab recorded minimum specific energy of 4.6 MJ/kg followed by UP (6.0 MJ/kg). Further, Punjab occupied the first place among all the States with 3334.8 kg/ha average yield, which is about 31% higher than the average productivity (2550.5 kg/ha) of the regions considered under the study. However, use of commercial energy was found maximum in Punjab (91.7%). Therefore, by ensuring optimal energy inputs in different regions wheat production in the Country could be increased.     

Methodological considerations of irrigation energetics

Methods are described to assess the total energy inputs for the irrigation of different crops. Energy yields as main products such as grain and as total biomass have been worked out. This methodology is illustrated with data from a sample farm growing wheat, paddy, berseem, sorghum fodder, and sugarcane. Energy inputs have been computed for the primary fuels used to generate electricity for pumping water. Fixed inputs embodied in materials, equipment and labor have been amortized for their expected lifetime. Compared to the energy yields in the main products, inputs in irrigation involved 6.8% for sorghum fodder, 13.9% for berseem, 15.2% for wheat, 15.9% for sugarcane, and 37.0% for rice.     

Energy inputs and crop yield relationships in greenhouse winter crop tomato production

In this study, energy use patterns and the relationship between energy inputs and yield for single crop (winter) greenhouse tomato production were examined in Antalya province, one of the most important greenhouse centres in Turkey. Data were collected using face-to-face surveys from 85 farms producing winter greenhouse tomatoes. The results indicated that the bulk of energy was consumed in fertilizer (38.22%), electricity (27.09%), manure (17.33%) and diesel-oil (13.65%). Average yield and energy consumption were calculated as 57,905.1 kg/ha and 61,434.5 MJ/ha, respectively. Results also determined an output–input ratio of 0.8 and a respective energy productivity and specific energy of 1.061 MJ/t and 0.94 kg/MJ. In addition, the Cobb Douglas production function was applied to test the relationship among different forms of energy consumption. The findings suggested that single crop tomato producers must optimize their use of indirect energy resources. Single crop producers applied an excess use of chemicals, resulting in an inverse effect on yield as well as imposing risks to natural resources and human health. This research suggested an expansion in energy use training opportunities to greenhouse farmers in the region.     

Potential of bio-hydrogen production from dark fermentation of crop residues: A review

This study provided an estimate of the potential of bio-hydrogen production from dark fermentation of crop residues on a worldwide scale. The different crop residues reviewed included sugarcane tops, leaves and bagasse, corn straw, corn cob and corn stover, wheat straw, rice straw and husk, soybean straw, oil palm trunk and empty fruit bunch, sugar beet pulp, cassava residue, barley straw and sweet sorghum bagasse. Among these crop residues, wheat and rice straws are produced in the highest amount although sugarcane dominates crop production on a worldwide scale. Based on the bio-hydrogen yields reported in literature, estimated worldwide bio-hydrogen potential is highest for untreated rice straw at 58,002 Mm³/year followed by untreated wheat straw at 34,680 Mm³/year. This corresponds to a bio-energy potential of 623 PJ/year and 373 PJ/year for raw rice straw and wheat straw respectively while pre-treatment of the crop residues significantly increases the bio-hydrogen and bio-energy potential. While dark fermentation of crop residues offers a huge bio-energy potential, the process suffers from several constraints that hinder its implementation. As such, coupling of the dark fermentation process with the anaerobic digestion process as a two-stage process seems the most economically viable option for large-scale implementation.     

Potential of two cardoon varieties to produce biomass and oil under reduced irrigation and weed control inputs

Cardoon (Cynara cardunculus L.) is an important perennial energy plant, which may produce sufficient biomass under reduced inputs. A 4-years field study was conducted in northern Greece and was repeated for three years in central Greece to determine the productivity of two cardoon varieties (‘Bianco Avorio’ and ‘C12’) under different water (irrigated or non-irrigated) and weed control (weedy or weed-free) conditions. In northern Greece, the density of weeds grown with cardoon increased as years went by, but in central Greece decreased. The absence of irrigation and the presence of weeds significantly reduced cardoon dry biomass, seed and oil yields, especially in the first two years of cultivation. In both environments, irrigated with 90 mm cardoon achieved 22–42% and 35–42% greater dry biomass and seed yield, respectively, than achieved the non-irrigated crop. In weedy cardoon, the dry biomass or seed yields reductions were 33–66% or 41–64%, respectively, in central Greece and 21–95% or 8–99%, respectively, in northern Greece. In central Greece cardoon productivity increased as years went by, but in northern Greece decreased. Generally, the cv. C12 was more productive than the cv. Bianco Avorio. Conclusively, the cardoon cv. C12 could provide satisfactory dry biomass, seed and oil yields for energy use in semi-arid Mediterranean fields, without irrigation or weed control inputs, on condition that they have been successfully established the first year. However, cardoon should be irrigated and weeded in order to provide sufficient yields.     

Prospects for using polymer ceramic composite films in solar engineering and agriculture

Data are presented on the increase of the temperature by 15°C with the use of a film containing 1% of a functional ceramic, and the evaluation of the economic effectiveness of the heated agricultural facilities and the various solar heating and drying systems with the transparent enclosures upon replacing the conventional film or glass with this composite material. The energy savings thanks to the use of the ceramic are 288 000 euros/ha, the crop yield increases by 35% or 21 tonnes/ha, the reduction of the energy consumption for the same productivity is 288 000 euros/ha or a total of 3556 to 4800 million euros per year; the additional income plus the energy savings amounts to 298 500 euros/ha. The payback time in terms of the income plus the energy savings is 0.0101 to 0.0109 year.     

Energy and water tradeoffs in enhancing food security: A selective international assessment

Rice is the major staple food in most Asian countries. However, with rapidly growing populations, sustained high productivity and yields through improving water productivity is critically important. Increasingly complex energy–agriculture relationships require an in-depth understanding of water and energy tradeoffs. This study contributes to energy and food policies by analysing the complex energy, water and economics dynamics across a selection of major rice growing countries.The results show that tradeoffs exist between yield and energy inputs with high yield attributed to higher levels of energy input. The selected developed countries show higher energy productivity, relative to all other energy inputs, compared to the selected developing counties, owing to enhanced mechanisation, on-farm technology and improved farm management. Among all countries, China has the highest water productivity due to water-saving irrigation practices. These practices offer opportunities for developed and developing countries to increase water productivity at the same time taking advantage of economic and energy benefits of reduced pumping.Sustained production from agriculture is vital to food security. Improved irrigation practices can offset environmental footprints in the short run but their large-scale implementation remains an issue. In the long run, investments are needed to buffer the negative impacts of food production on the environment. Investments to boost water productivity and improved energy use efficiency in crop production are two pathways to reduce energy dependency, enhanced natural resource sustainability and ensuring future food security.     

Bioenergetics of bullock power

A pair of Haryana bullocks, by the age of three years, consume about 113 GJ (embodied energy) and need about 445 GJ more of feed during the next ten years of working life on the farm (maintenance energy). The scrap value of the bullocks utilized fully is about 15 GJ. Energy inputs into a pair of bullocks (1 hp) per working day on large farms (80 working days/yr) total 0.7 GJ and on small farms (176 working days/yr) 0.3 GJ. From the point of view of the total energy resources of the community, using bullocks is uneconomical.     

Energy input–output analysis in Turkish agriculture

The objective of this study is to determine the energy use in the Turkish agricultural sector for the period of 1975–2000. In the study, the inputs in the calculation of energy use in agriculture include both human and animal labor, machinery, electricity, diesel oil, fertilizers, seeds, and 36 agricultural commodities were included in the output total. Energy values were calculated by multiplying the amounts of inputs and outputs by their energy equivalents with the use of related conversion factors. The output–input ratio is determined by dividing the output value by the input value. The results indicated that total energy input increased from 17.4 GJ/ha in 1975 to 47.4 GJ/ha in the year 2000. Similarly, total output energy rose from 38.8 to 55.8 GJ/ha in the same period. As a consequence, the output–input ratio was estimated to be 2.23 in 1975 and 1.18 in 2000. This result shows that there was a decrease in the output–input energy ratio. It indicates that the use of inputs in Turkish agricultural production was not accompanied by the same result in the final product. This can lead to problems associated with these inputs, such as global warming, nutrient loading and pesticide pollution. Therefore, there is a need to pursue a new policy to force producers to undertake energy efficient practices to establish sustainable production systems.