Introduction

Key pre-conditions for the realization of 2030 visionare: food security, energy security and employment. This is the essential empowerment to generate the necessary income to access and sustain the provision of the basic needs of life at a level consistent with the middle income industrial nations.The main focus must be on the agricultural sector which is currently supporting over 70% of the population producing 30% of GDP and generating over 60% of the foreign exchange earnings.

Cereal and livestock production may need to increase globally between 60 and 100% by 2050 because of the increasing demand. In sub Saharan Africa (SSA), this will require considerable investment in agricultural research. However the necessary food increases will have to occur as climate is changing and climate variability increases. There is need to consider innovative technology options that can bring a breakthrough in food production to meet the coming challenges as the world warms up to 4oc (Thornton et al 2011).  Bio fuels offer an option for rural energy supply for agricultural mechanization and rural industrialization with a positive contribution to climate change.

The main bio fuels are bio-ethanol, bio-oil,bio-diesel, biogas, producer gas (gasification). Bio -ethanol is produced from sugar cane, maize, sorghum and cassava among others. The major producers are Brazil and United States of America;countries with vast agricultural land and thus eliminating conflict with food production. Bio-oil/bio- diesel is produced from Soya, rape seed in large scale mechanised farming in Europe and North America and in small scale from the tree crops such as Jatropha, croton and castor in the less developed countries (LDC). Traditionally the latter bio-oil crops grow in the wild or are hedge crops for households. Proposals for large estates of Jatropha, croton or castor in LDCs are likely to be in conflict with food production (GEF 2011). However there are agro-forestry and inter-cropping options particularly for castor which should be considered for expansion.

Castor can grow in virtually all Kenyan agro-ecological zones and is usually grown as an intercrop. It can also be grown as a rotation crop. In this paper we shall show that castor can contribute significantly to energy for rural households as well as for agricultural mechanization and rural industrialization. The crop can also be used as a rotation crop in conservation farming.

The Development Challenge

Kenyan expenditure on fossil fuels in the last few years is shown below.

First half year 2011 was Ksh 166.4 and 2010 it was 107.4

Trade deficit in Ksh {Billions} by 2011 june 410 and 287 by 2010 june

Annual imports in million tones 3.8 for 2011 and 4.2 for 2009

This situation may be mitigated but not entirely eliminated by the recent fossil fuel discoveries because investment and expertise formining and processingwill still be sourced externally.The fact that investors are currently calling for reduced cost of energy underscores the need for a significant measure of energy self-relianceespecially in remote rural locations.In this paper we shall show how the country can apply castor both as an energy crop as well as a rotation crop in the quest for the reclamation of up to 2m ha of degraded land as well as expansion of 1.2mha new land earmarked for conservation farming under vision 2030

The main objectives of this paper are:

        i.            To show the potential of castor in contributing to rural energy for Kenyan households and agricultural mechanization.

      ii.            To high light the technical feasibility of castor bio-oil in contributing to farm level energy need

Potential of Castor as a Bio-oil Energy cash crop

Castor (Ricinuscommunis) is a perennial shrub from the Euphorbiaceae family that likely originated in Abysinnia or modern Ethiopia. Historically the oil is an ancient product that has been in use for thousands of years as lamp oil and medicines andmore recently for a long list of industrial applications (GTZ, 2009).Traditionally the oil is used in Kenya for cosmetic purposes as well as for softening the traditional leather attire.An industrial global market exists for different grades of castor oil, from crude to industrial and to pharmaceutical uses.

Agronomy

Data collected in Kenya by GTZ (now GIZ) show that castor can grow in virtually all agric-ecological zones as summarized in map 1.

 

Agronomic Parameter

Rangecxiii

Optimalcxiv

Kenya (from Survey)

Annual Temperature (°C)

15?39°C

20?30°C

Range – 14.2?24.2°C

Mean – 18.6°C, Median 17.6°C

Annual Rainfall (mm)

400?2,000 mm

750?1,000 mm

Range – 615?1,801 mm

Mean – 1,333 mm, Median – 1,038 mm

Altitude (m)

0?2,000 m

300?1,800 m

Range – 645?2,346 m

Mean – 1,690 m, Median – 1,769 m

Soil

Well drained, loam that can tolerate moderate

Acidity

Loamy, sandy.

 

 

 

 

 

 

 

 

 

 

 

 

 

Agro-Climatic Parameters for Castor, from Literature and Kenya Survey.Source: GTZ, 2009

The experiences in Kenya show that very little pesticides is used for the crop grown wild or as an inter-crop or as a hedge. Consequently the yields are generally low with an average of 231 kg per acre in 2007.Reports from India indicate yields as low as 350 kg per acre. The oil content of the seeds ranges between 35 to 55%. For oil density of 959.3 kg per tonne, one tonne of seeds will yield between 365 and 573 litres of oil.Research conducted by Kenya Agricultural Research Institute (KARI) twenty years ago show that the variety named “KC4’’ can yield up to 1,415 kg per acre with seed oil content of 48.8% Chart 2 shows yield per acre in six largest producing countries in 2007.

Management

Castor is generally propagated by direct sowing 6-8 cm deep in rows spaced 9-1.2 meters and 0.2 -0.6 meters within the row for pure stands 1×1, 2×2,3×3, 4×4 and 5×5 for inter crops thinned every season as the canopy grows. Seeds which should be treated before planting with 3 grams per kg of Thiram, fungicide to avoid root rot and Alternaciablight in areas of low temperature and high soil moisture. The seeds will typically emerge in 7 to 21 days. It is recommended by the Philippines Council for Agriculture as one of the short to medium term species for growing in agro-forestry systems involving food crops, trees and nitrogen fixing species. Weeing twice is  recommended one pre emergence and second post emergence.Adequate fertilizer application of NPK of upto 90-135 kg per ha of nitrogen and 37-56 kg per ha of phosphorous are recommended. The crop matures 140 to 170 days.

Harvesting is normally done by hand. The tree may be replaced after five years or earlier depending on the expected yield.

 Economics of Castor

Based on KARI trials and observations by Waweru of Biossal (personal communications) economics of castor can be analysed. According to Waweru yields of 2,000 kg per acre per year (usually two harvests) are possible with local varieties. Dwarf varieties from Kaima Institute in Israel are estimated to double the yield of the Kenyan local varieties.Moreover the harvesting of dwarf varieties may be mechanized. The practice with the local perennial varieties is to space them 1m tx 1m until the first crop is harvested in 4 months; then thin them down to 2m x 2m for the second crop and then 3m x 3m in the third year.

Harvesting and post-harvest processing of stems leaves and cake may facilitate gasification to produce power. 2 Kg of castor seeds can produce one litre of oil when proper processing is carried out. Due to production of toxic Ricin, castor processing should be restricted to properly trained professionalsin central locations. The cost of processing is estimated at Kes 10.00 per litre. Therefore the direct cost of one litre of oil at 20/= per kg seed is

2 x 20/= + 10 = 50/= per litre

Add 40% for storage and distribution to arrive at 70/= per litre retail. This price compareswell with the current price of kerosene at 90/= per litre.

Conclusions

Castor crop has the potential;

                               I.            Bio oil production as an inter crop

                            II.            Rotation crop for conservation farming

                         III.            Crop residue for gasification for power production

 

       Recommendations

 

1.0  Promotion of castor as a cash crop through value chain development

2.0  Creation of harvesting and post-harvest- processing and marketing support infrastructure similar to that for coffee and tea.

 

REFERENCES

1.      UNEP. (2012). Assessment and Guidlines for sustainable liquid biofuel production in developing countries.

      2.German Technical Cooperation, (GTZ). (2009). Oil seed study, Kenya.

3.                 3.International Food policy Research, (IFPRI), 2012. Global Food Policy Research Report, 2012.

4.                 4.Peter Waweru, Biossal Technology, personal communications.

5.      UNEP, FAO, UNIDO. (2012). Global Assessments and Guidelines for Sustainable Liquid Bio fuel Production in Developing Countries.  Final report, A GEF Targeted Research Project

 

 

 

 

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