Sugar cane continues to be the main raw material for ethanol production, generating about 7 thousand liters of product per hectare. However, other crops emerge in the agricultural scenario as an alternative and complement to the production of first-generation ethanol. Such crops are being tested for their productivity viability and a few others are already being used in the energy sector. That is the case of sweet sorghum, which today yields 2.5 thousand liters of ethanol per hectare, 12% of sugar content and between 11% and 15% of fiber.
Sweet sorghum has some qualities that make it a viable alternative to industries. In Brazil, the crop is already available throughout the South-Central region, especially in the State of São Paulo and in the Cerrado region. This raw material has better growth and productivity during summer, as its vegetative growth is optimized during this season, with sugar storage in the last stage of the cycle. With a little more genetic improvement and agronomic development, the crop can be cultivated in areas of interim-harvest, offering an extra complement of raw material when the mill is already in the harvest period. For already established industries, the possibility of extending the crop period represents the amortization of fixed costs and better use of the industrial park.
According to the commercial director of NexSteppe in Brazil, Tatiana Gonsalves, the monetary investment in sorghum is much lower when compared to sugar cane, while the investment in learning and dedication is huge. She explains that the crop has an array of significant differences in relation to cane, such as short cycle, planning and fast decisions needs, constant monitoring, assessment of integration between field/industry etc. “While mills create their learning curves, a reasonable number of companies try to evolve rapidly with the crop, not only genetically, but also in terms of agronomy. One of the main points is the need to master the establishment of plants’ stand, which is mandatory to achieve the minimum desired productivity of the crop”, says Tatiana.
With the proposal of showing mills the potential productivity of sweet sorghum as an alternative for ethanol production, Monsanto, through Canavialis – commercial brand of sugar cane improvement and technology -, released the “Sweet Sorghum Productivity Challenge” earlier this year. Five demonstrative fields were installed, with about 20 hectares each, in the following mills: CleÁlcool (Clementina/SP), Raízen Bom Retiro (Piracicaba/SP), V.O. (Catanduva/SP), Raízen Junqueira (Igarapava /SP) and Boa Vista (Quirinópolis /GO). These areas were selected by CanaVialis, among those that showed interest in including the cultivation of sweet sorghum in the last harvest, due to their location in areas that are important to the cultivation of sugar cane, and due to their need for raw material to complement the low availability of cane during the off-season.
“Monsanto has strongly invested in sweet sorghum genetic improvement research. The company has a research station near Uberlândia, in the state of Minas Gerais. Furthermore, the technical development area currently has 22 experimental fields to select and test future releases”, says Canavialis’ Marketing analyst, Vagner Kogikoski. Monsanto also has four commercial hybrids in the market, in addition to hybrids CV007, CV 147 and the newly released CV 568 and CV 198.
In addition to genetic improvement and the supply of hybrids, another important factor that leads mills to invest in technology is the provision of a structure focused on sweet sorghum, especially personnel, says Vagner. He suggests that monitoring and activities must be conducted on a regular basis, as this is a short cycle culture.
Raízen has been investing in the cultivation of sweet sorghum to produce ethanol and sugar for more than two harvests. The company is already reaping the results of the first tests made in July 2001, at the Jataí Unit, in the state of Goiás, and considers the products extracted from the plant as an alternative to the sugar cane off-season period. Raízen started with an experimental plantation in a 92-hectare area and has already obtained very promising results, taking into account the fact that the sorghum was not planted during its usual planting season. The test was made in order to verify crop behavior in the field and with the local weather, as well as occurrence of pests.
The second experience took place in an area of 1000 hectares of sweet sorghum planted in December 2001, in Piracicaba (SP). The harvest took place in April 2012. Finally, a third crop was planted in December 2012 (in a 650-hectare area), also in Piracicaba. This crop was harvested in April 2013.
The company started operating with the culture because it believes that investments in research and new technologies are part of the process of improvement of Brazilian production. Currently, the crop is adopted in the Piracicaba region, specifically in the city of Capivari, near the São Francisco Unit. The production of ethanol from sorghum still varies greatly from planting to planting and variety to variety, as it is a new crop and still under development. In the last harvest, the approximately 1000 hectares produced around 900 thousand liters of ethanol.
Research and supply
According to the commercial director of NexSteppe in Brazil, Tatiana Gonsalves, sweet sorghum has advanced both in genetic improvement and agronomic techniques. But she emphasizes that it is a challenge to cultivate grain crops, as they involve small seeds, the use of planters not mastered by industries, cultivation during rainy season and intense short droughts known as veranicos, and short cycles – significantly shorter than sugar cane.
“While the improvement focuses on crop fit, accumulation of Brix and juice, resistance to pests, among other challenges, the technological development area has as much or more work in fitting the enormous potential of a plant with short cycle and sugar accumulation in the sugar cane off-season”, she says.
For the company itself, the cultivation of sorghum is a challenge. Tatiana explains that there are experts in NexSteppe working with sorghum for 30 years, but who have started to invest in the energy market only two years ago. “We work with full improvement, including hybridization, use of molecular markers and hybrid seed production, to meet the market. We’ve built testing areas side by side, to evaluate materials, and closely follow the development of commercial areas. For a crop with so many challenges, we need to work together to achieve prosperity for all”, she says.
- High biomass production and high sucrose concentration
- Large acceptance by mills
- Planting occurs every 5-6 years
- Long cycle of 12-18 months (plant and ratoon cane), perennial culture
- Intensive and time-consuming genetic improvement
- Short cycle of 100 to 140 days (depending on the genetic material)
- Annual culture without economic use of crop shoots
- High biomass production in proportion to the period of cultivation
- Genetic improvement being conducted by various companies and rapid return
- Concentration of sugars such as sucrose, glucose and fruitage
- Acceptance by mills still small
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