Since there are no currently active contests, we have switched Climate CoLab to read-only mode.
Learn more at
Skip navigation
Share via:


Production of bioethanol from invasive macrophytes to generate electricity for low income neighborhoods in Cochabamba City



Cochabamba is the third largest city in Bolivia with more than 700,000 people . It’s estimated that by 2030 this population will increase in 50%. The uncontrolled growth has developed many marginal neighborhoods without access to potable water and electricity.

Cochabamba is fifth most contaminated city in South America. The excessive use of fossil fuels, solid waste pollution and lack of sewage treatment in many areas has affected the quality of air and water in Cochabamba. It is located in the Rocha River Basin; an important system of Sub-Andean rivers and lagoons, which are important water resources for irrigation and consumption.

The basin is composed by the Rocha River, which is heavily polluted due the discharge of waste water. Part of the river’s stream is drained to Alalay Lagoon, an important biodiversity hotspot that used to be a touristic place and important fishing area. The lagoon hosts 134 species of vertebrates, including 2 IUCN red list species.  

In the last decade the lagoon has been covered by macrophytes due eutrophication caused by pollution. The lack of oxygen, consumed by macrophytes, has affected the wildlife and produced bad odors. As consequence, the lagoon ceased to generate resources for the people in the surrounding area, which is the poorest one in the city. 

The municipality spends about 1 million dollars per year removing the macrophytes, but the main and most expensive issue is to find what to do with the residues. We propose to produce bioethanol from macrophytes residues and complement it with corn stover from the surrounding area, which is one of the most productive areas in the country. Pistia stratiotes, the invasive macrophyte at Alalay, has great proved yields producing bioethanol. In addition, the conditions of dry weather are ideal to dry without using energy; and the high content of starch and temperature conditions favor the fermentation of carbohydrates.  

Category of the action

Reducing emissions from electric power sector.

What actions do you propose?

The collection of macrophytes will take place by algae collectors in Alalay Lagoon. This technology was developed in the first half of the twentieth century in order to clean the Florida swamps. During the last years this kind of technology has evolved and nowadays there is advanced systems for the collection and transportation of macrophytes. The selected harvester is powered by a 22 HP engine core. It has a hydraulic system navigation paddle rotation, and a charging system with two belts coated moved by an automated hydraulic system platforms. The capacity of the system is 3.1 m3 of macrophytes collected per hour. By removing the abundance of algae, the nutritional and toxic substances are reduced and the algae biomass could be used to produce ethanol. 

After harvesting macrophytes, is necessary to dry them to produce ethanol. The weather conditions of Cochabamba are ideal to use no-electriity drying systems that could be install in the lagoon area.

The efficiency of bioethanol production from macrophytes has been proved. Recent studies (Mishima et al., 2008) (Soda et al., 2013) (Ludo et al., 2013) have shown that Pistia stratiotes, the invasive macrophyte at Alalay lagoon, has a high capacity for etanol bio production thanks to its high biomass content (Soda et al., 2013). Pistia stratiotes L. has slightly higher starch contents and lower contents of cellulose and hemicellulose, promoting a more efficient fermentation (Julias et al., 2012). Through a fermentation process with east such as Saccharomyces cerevisiae and an after distillation and purification of the product, it can be obtained a high quality ethanol (90-95%) (Mishima et al., 2013). The use of corn stover to produce ehtanol has been also proved, being a material tih high efficiency rates. The process to produce ethanol from corn stover is the same to produce from macrophytes. 

The Stream of Rocha River has the potential to produce hydroelectric power to produce energy, through the installation of horizontal Pelton turbines located in four strategic areas where electricity is needed. With an install capacity of 5 kW, the hydroelectric system will provide 40 MW year, that would be used to light public areas. This complement won’t only help to generate energy; it will also generate awareness of the care of the river.

Both projects must be integrated with an environmental education program in the city, to generate awareness to reduce the consumption of energy and teach effective ways to save energy.

Who will take these actions?

In Bolivia there some industries are involved in the alcohol production, especially Guabirá and Unagro Sugar Mill, which could be allies in the development of our project. However, the production of bioethanol from macrophytes is a new industry in the country, who have been limited to some small research in education centers. The Project will be implemented by a private enterprise with the support of the Cochabamba municipality, who already had a Project implemented to recover the Rocha River basin.

Local mechanical manufacturers of Cochabamba will be involved in the development of the new algae collector with the help of State University, specifically mechatronic and sciences and the technology departments. The State University will also be involved in research and development, and the diffusion and implementation of the environmental education program.

Where will these actions be taken?

The project will be implemented at Alalay Lagoon in Bolivia. The lagoon is the most important urban lagoon and it has an important economic value. The municipality is interested in investing to solve the environmental problems in the lagoon. There are big pressures from the citizens to find a sustainable solution to the pollution problem, specifically the excess of invasive macrophytes in the lagoon. 

The influence area of the Lagoon Alalay was formed by a diversity of people, where the majority is migrant populations from other departments of Bolivia. The Lagoon belongs to the district 6 of Cercado, located in the southeast part of the city. This district is categorized  for being the most populated in the city and the poorest at the same time. 46,000 people lived in the district in an area of 89.27 square kilometers. This represents  the second largest population density in the municipality with 698.33 habitants per square kilometer. In addition, 525.024 habitants from other districts of the municipality are indirectly affected.

The 50% of the people are in the age between 0 and 29 years, showing the future labor potential that exists in the zone. Unfortunately, the district presents a very high and worrying unemployment index with 58% of the people without job, being in the majority women showing the strong gender inequality existing in the district. The zone of interest has a high rate of illiteracy of 92.64%, with the 60% of people without home ownership, with a 43.2% with access to basic services and electricity and low levels of access to health care. Because of these factors, it is of vital importance the development of this district for the social and economic welfare of the entire municipality.

How much will emissions be reduced or sequestered vs. business as usual levels?

The poor areas of the city who don't have access to electricity currently use gasoline to run electricity generators. By using bioethanol, people who currently use gasoline to produce energy will spend 33.5% less and release 12% less CO2. Bioethanol  Every year the use of bioethanol produced by the project will capture 798 tons of CO2.

What are other key benefits?

Is estimated that the project will generate incomes of 2,010,130 U$S per year and 520 jobs; it will also produce enough electricity for 6,340 families. Indirectly, the project will benefit the corn producers, the local municipality, private enterprises around the lagoon and around 46,000 people living in the surrounding area; due the improvement of environmental quality and the enhancement of the appearance of the city through the recovery of the biggest green area in Cochabamba. 


What are the proposal’s costs?

With an investment of 6,016,037 U$S, it will generate 2,010,130 U$S per year, giving  a return time of the inversion of 3 years and an internal return rate to ten years of 40%. 

Time line

In the short term the project will be implemented in Cochabamba to produce enough resources to recover the initial investment and set the bases of the first green city in Bolivia. 

In the medium term we want to implement similar projects in other Bolivian cities, establishing the first bioethanol production company in Bolivia. 

In the long term we want to spread the initiative all over Latin America, invest in research and development, and begin to cerate other technologies in other areas of renewable energy production. 

Related proposals


Ayala, R., Acosta, F., Rejas, D., Van Damme, P., & Mooij, W. (2007). Management of Laguna Alalay: a case study of lake restoration in Andean valleys in Bolivia. Aquatic Ecology, 41, 621-630.ENDE. (2015). National prices and electricity rates. National Power Company.

EPA. (2014). Clean Energy Calculations. United States Environmental Protection Agency.

ESHA. (2004). Guide on How to Develop a Small Hydropower Plant.·        

FAO. (1979). Water, mineral and protein content and productivity of aquatic plants. En Handbook of utilization of aquatic plants (pág. 176). FAO

Gómez, E. (2014). Rapid Evaluation of Energy Sector in Bolivia.

INE. (2012). Population census. La Paz: National Institute of Statics.

Kadam, K., & McMillan, J. (2002). Logistical aspects of using corn stover as a feedstock for bioethanol production. National Renewable Energy Laboratory.

Luo, G., Shi, W., Chen, X., Ni, W., Strong, P., Jia , Y., & Wang, H. (2011). Hydrothermal conversion of water lettuce biomass at 473 or 523 K. Biomass & Bioenergy, 35(12), 4855-486.

Miler Neilan, R., & Kenneth, R. (2014). Simulating the effects of fluctuating dissolved oxygen on growth, reproduction, and survival of fish and shrimp. Journal of Theoretical Biology, 343, 54-68.

Mishima, D., Kuniki, M., Sei, K., Soda, S., Ike, M., & Fujita, M. (2008). Ethanol production from candidate energy crops: Water hyacinth (Eichhornia crassipes) and water lettuce (Pistia stratiotes L.). Bioresource Technology, 99(7), 2495-2500.

Ministry of Agriculture of Bolivia. (2012). Agricultural compendium of Bolivia.

Mitsch, W., & Gosselink, J. (2000). The value of wetlands: importance of scale and landscape setting. Ecological economics, 35(1), 25-33.

Morales, E., & Rivera, S. (2012). Choice of macrophyte substrate in the use of diatoms as indicators of pond water quality assessment: Preliminary data on the case of Alalay pond (Cochabamba, Bolivia). Lakes, reservoirs and ponds, 6(1), 20-42.

Nielsen, B. (1995). Questions Relative to Harvesting & Storing Corn Stover. Agronomy Extension publication - Purdue University.

Saravia, A., & Rua, A. (2005). A look at the CVM under the ecosystem approach: The case of Alalay lagoon in Cochabamba, Bolivia. Resumen de ponencia presentada en el Segundo Congreso Latinoamericano de Economistas Ambientales , 193-222.

Soda, S., Mishia , D., & Ike, M. (2013). A co-beneficial system using aquatic plants: Bioethanol production from free-floating aquatic plants used for water purification. Water Science and Technology, 67(11), 2637-2644.

Van Damme, P., Romero, A., Goitia, E., Rojas, J., Cadima, M., Arce, O., & Romero, M. (1997). Evaluación de estrategias y alternativas para la recuperación y la conservación de la laguna Alalay. Cochabamba: UMSS.

Wagner , J. (2009). Feasibility Study for Small-Scale Ethanol Production in Minnesota. Marshall, MN: BBI International.

WHO. (2014). WHO’s Ambient Air Pollution database . World Health Organization.