Water falls through these enormous pipes to activate the 20 turbines of the Itaipu hydroelectric plant on the Brazilian-Paraguayan border. Caring for the water in the reservoir, as well as reducing the pollution in the rivers that run into it, help make this binational plant one of the most efficient in the world, with a projected useful life of 184 years. Credit: Mario Osava/IPS

By Mario Osava
FOZ DO IGUAÇU, Brail, Feb 10 2020 (IPS)

Fomenting biogas production among agricultural producers may seem at first glance to be a distraction from the purpose of Itaipu, the giant hydroelectric power plant shared by Brazil and Paraguay, but in fact it is part of their energy business strategy.

“Protecting the quality of the water (in the reservoir) is essential for power generation,” explained General Luiz Felipe Carbonell, coordination director in Itaipu Binacional, the company that manages the power plant on the Paraná River, which forms part of the border between the two countries.

The efficiency of Itaipu, the second largest hydroelectric power plant in the world in terms of potential, has been proven by the record amount of electricity generated: 103 million megawatts/hour in 2016, which exceeds the best performance of China’s Three Gorges power plant, whose installed capacity is 60.7 percent higher.

While the Brazilian-Paraguayan plant has a potential of 14,000 MW, the potential of Three Gorges is 22,500 MW. But generation depends on water flow, turbine efficiency and demand.

Biogas production in southwestern Brazil is on the rise, mainly due to the use of livestock manure. In the west of the state of Paraná, part of whose rivers flow into the Itaipu reservoir, there were 4.2 million pigs, according to the 2017 agricultural census.

Sedimentation is a risk that can shorten the life of a hydroelectric plant, which in Itaipu’s case is estimated at 184 years. In addition to the quantity, it is necessary to consider “the quality of the sediments,” noted Marcio Bortolini, adviser to the coordination director.

Organic waste, like the manure from pig farming, drives the proliferation of especially harmful species, like the golden mussel (Limnoperna fortunei), an invasive species that appeared in the Itaipu reservoir in 2001, he explained.

The mussel from Southeast Asia often clogs pipes and brings turbines to a halt when it latches onto hard surfaces.

Bortolini described this situation when he took part in a Jan. 27-29 workshop on biogas for Brazilian journalists, organised by IPS and the International Center for Renewable Energy (CIBiogás), with support from the U.S.-based Mott Foundation.

General Luiz Felipe Carbonell, Itaipu Binacional’s coordination director, says that caring for the environment is vital for the power plant’s productivity and longevity because it reduces sedimentation, among other things. Using organic waste to produce biogas helps eliminate invasive species in the reservoir that damage the dam and equipment. Credit: Mario Osava/IPS

“Without good water quality, several species of fauna will settle in and affect our reservoir and the machinery,” said Carbonell, one of the army officers appointed to Itaipu and the Brazilian government under President Jair Bolsonaro, who himself retired from the army as a captain in 1988.

Efforts to combat the golden mussel and protect water quality managed to reduce the population of the invasive shellfish and keep it under control, said Itaipu administrators during the workshop held at the CIBiogás facilities in Foz do Iguaçu, the main city where the power plant is located.

“Besides the golden mussel, a danger to our maintenance service, we have the freshwater hydroid (Cordylophora caspia), an invasive species that corrodes concrete, and therefore represents a physical danger to the dam,” said the general.

The main cause of these threats is organic waste, which is why “we use it to produce biogas and at the same time to improve the environment and the quality of life of the populace,” Carbonell told IPS at the plant’s facilities.

Therefore, disseminating biogas as a source of heat, biomethane and bioelectricity, and promoting other energy alternatives, such as solar, hydrogen and less polluting batteries, does not distract Itaipu from its business of generating hydroelectricity, he said.

Ademir Eischer produces biogas using the manure from the 1,200 pigs on his farm. He is one of the 18 farmers who supply the mini biogas power plant in the municipality of Entre Rios, in the west of Paraná state. The main benefit, he said, was the elimination of the stench of the raw manure that fertilises his hay crop next to his home, because biodigestion removes the strong odour by making use of the gases. Credit: Mario Osava/IPS

The same is true with regard to the reforestation of the surrounding area, where 44 million trees have been planted, because it protects the environment and the reservoir by reducing erosion and maintaining the water table. These are measures that support water security, an indispensable factor for the business.

The general also mentioned the plant’s efforts to boost the well-being of the surrounding population, and said health conditions have improved as a result of the projects.

Itaipu runs several social, economic development and technological programmes. Electric vehicles, a biodiversity corridor, tourism, local development and child protection are part of this focus, as is the Federal University of Latin American Integration, installed within the Itaipu area.

“Cultivating Good Water” stands out as a wide-ranging programme, initiated in 2003, in which more than 2,000 public and private entities have been involved in more than 60 social, economic and environmental actions, including fish farming, medicinal plants, garbage recycling and recovery of more than 200 micro-watersheds.

The programme is based on the principle of caring for water in order to generate more electricity for longer periods and to produce biogas for energy, environmental and water quality purposes.

Biofuel production was increased at the initiative of Itaipu, in a mission transferred to CIBiogas, founded in 2013 as an autonomous, non-profit entity. Itaipu is one of its 27 partners, which include the United Nations Industrial Development Organisation (UNIDO) and the United Nations Food and Agriculture Organisation (FAO).

From a biogas producer’s point of view, the environmental benefits have more to do with the air than with the water.

For example, the stench of “raw” manure has almost disappeared on the farm where Ademir Eischer uses manure to grow hay, his main source of income.

With just three hectares of land that runs up against the highway in the small municipality of Entre Rios, Eischer – who also fattens 1,200 hogs – can’t expand his pig farming operation, and the field planted with hay almost reaches his house.

“I’ve been working in haymaking for a long time and decided to start producing biogas because of the smell. When the manure goes through the biodigester, it loses 70 to 80 percent of its odour and we gain a lot in terms of quality of life,” Eischer told IPS during a visit to his farm.

Biodigestion consists of extracting methane (CH4), hydrogen sulphide (H2S, mainly responsible for the bad smell) and carbon dioxide (CO2), which make up the biogas, from the manure that can then fertilise the soil without the pollution and smell of the gases.

The production of biogas from the manure of pigs like these ones on Ademir Eischer’s farm is a new business with great potential in the western part of the state of Paraná, in southern Brazil, an area where there are more than four million hogs. Biogas also eliminates the waste that pollutes local rivers and leads to sedimentation in the Itaipú reservoir created by the dam built for the giant hydroelectric plant shared by Brazil and Paraguay. Credit: Mario Osava/IPS

Methane, which is removed in much greater proportion than the other gases, is 21 times more aggressive than carbon as a greenhouse gas that warms the planet, which is why its extraction and use as a source of energy contribute greatly to mitigating the climate crisis.

Eischer is one of the 18 pig farmers whose biogas generate almost all the electricity consumed by the municipal government of Entre Rios do Oeste, population 4,600, which inaugurated its own mini power plant in July 2019.

Another local pig farmer and biogas producer, Claudinei Stein, highlighted other benefits: the “reduction to almost zero of mosquitoes” that used to pester him and his employees on the farm, while posing the risk of transmitting diseases.

In addition, the manure minus the gases has improved the fertilisation of the soil where he grows soybeans and corn on his 12 hectares.

Pedro Colombari says that with the bio-fertiliser resulting from biodigestion he has managed to improve his pastures to the point of fattening 10 cattle per hectare per year – quite a feat in a country where, on average, farmers only raise a little more than one cow per hectare.

“Now I’m trying to double that productivity on an experimental two hectares,” with more intensive fertilisation and irrigation, he told IPS.

His 400-hectare farm, where he raises 5,000 pigs and 400 head of cattle and grows soybeans and corn, generates its own electricity using biogas, in a microgrid in which several generators, using varied sources and batteries, can operate together and outside the main grid, offering greater energy security.

The Paraná river, reduced in size by the concrete behemoth of the binational Itaipú dam. Credit: Mario Osava/IPS

By Mario Osava
FOZ DE IGUAÇU, Brazil , Dec 20 2013 (IPS)

As they build huge hydropower dams, the Brazilian government and companies have run into resistance from environmentalists, indigenous groups and social movements. But the binational Itaipú plant is an exception, where cooperation is the name of the game.

Involved in a total of 65 environmental, social and productive activities, the Cultivando Agua Boa (Cultivating Good Water – CAB) programme is led and supported by activists. Sectors of the government are considering using it as a model to be replicated in other major infrastructure projects, to mitigate impacts and conflicts.

Compared to what is happening in the rest of the hydroelectric dam projects, “it’s a stride forward,” said Robson Formica, head of the Movement of People Affected by Dams (MAB) in the southern state of Paraná, where the giant Itaipú hydropower complex is located on the border between Brazil and Paraguay.

Itaipú Binacional, the company that operates the hydroelectric plant, decided to guarantee efficient long-term electricity generation by caring for the Paraná river basin to ensure both the quantity and quality of the water. That has paved the way for cooperation with environmentalists.

More than 80 percent of Brazil’s electricity comes from its rivers, which means the country’s energy security depends on rainfall and on the best possible use of water.

Itaipú’s CAB programme was launched in 2003, two decades after thousands of rural and indigenous families were displaced in order to flood their land and fill the 1,350-sq-km reservoir. The dam is the world’s largest hydroelectric power producer.

Formica said CAB’s activities are “important, but limited and isolated.”

“They fail to establish a policy for local development, or for structural changes in the area in question,” added the head of MAB, which estimates that hydroelectric dams have displaced around one million people in Brazil.

The demand that the company take over functions that normally fall to the state has gained force as mega-dams and other infrastructure projects that drastically modify extensive areas of rainforest and other habitats mushroom around the country.

In addition, environmental laws are requiring compensation for damage caused.

In the case of Itaipú, that requirement is particularly justified. It is an unusual company, run by two different national governments, and it brought in revenue of 3.8 billion dollars in 2012.

The land and rivers where the complex operates along the border between Brazil and Paraguay contain the enormous hydroelectric plant, the reservoir, 104,000 hectares of land that is under environmental conservation, the University of Latin American Integration and the Itaipú Technological Park.

The CAB programme is active in 29 municipalities in Brazil covering a total surface area of 8,339 sq km, with one million inhabitants, along a 170-km stretch of the Paraná river and reservoir.

The programme’s 65 activities include assistance to indigenous communities, aquaculture, medicinal plants, biogas and environmental education – a concerted effort connected by the central aim of taking care of the water.

For example, CAB’s sustainable rural development activities revolve around organic agriculture as the top priority, aimed at reducing the pesticides polluting the reservoir.

“We started out with 186 families; today there are 1,180 families participating, and there are 2,000 organic gardens,” said Nelton Friedrich, Itaipú director of coordination and the environment.

The Itaipú Platform of Renewable Energies was also created, to protect the rivers from animal manure. The manure is converted into biogas, which generates electricity, thus creating another source of income for local farmers while curbing pollution of the water.

Family farming is the main livelihood around the reservoir, where there are millions of pigs, barnyard fowl and cattle on 26,000 smallholdings. If allowed to run into the water, the manure would cause excessive build-up of nutrients and the proliferation of aquatic weeds, which reduce the oxygen in the water.

This process is called eutrophication, explained Cícero Bley, Itaipú’s superintendent of renewable energies. “Pollution by organic waste is more common than pollution by toxic agrochemicals,” and in some cases makes constant cleaning of reservoirs necessary, he said.

It takes nearly 30 days to renew the water in the Itaipú reservoir, compared to much shorter time-frames in other dams.

On the Madeira river in the northern Amazon jungle state of Rondônia, where the Santo Antonio and Jirau hydroelectric dams just began to operate, it takes just two or three days to renew the water in the reservoirs, said Domingo Fernandez, Itaipú’s chief researcher on fish.

Clean-up and reforestation are thus clearly necessary along the banks of the reservoir to keep the water healthy and productive. The CAB programme planted more than 24 million trees around the Itaipú reservoir.

The initiatives follow a methodology that is also key, expanding the activities to the entire watershed, “because nature organises itself by watershed,” Friedrich said.

The model followed is based on the concept of shared responsibility, involving all local actors, from public and private companies to civil society and universities, with community participation – a kind of “direct democracy,” he explained.

To that end, management committees were created in the 29 municipalities, made up of an average of 57 representatives of different sectors, after numerous meetings were held for awareness-raising and debate on problems that have arisen.

The so-called water pacts, which are community commitments signed in ceremonies, drive the design and collective implementation of the plans and projects.

These initiatives point out a good path to follow, but are far from filling Itaipú’s social debt, said Aluizio Palmar, founder of the Centre for Human Rights and Popular Memory and a former secretary of the environment and communication in Foz de Iguaçú, the Brazilian municipality where the binational dam operates.

Construction of the hydropower plant between 1975 and 1983 displaced rural families, many of whom did not hold legal title to their land, which they needed to obtain compensation. The families joined the ranks of the people living in the favelas or slums, and the rates of violence in Foz de Iguaçú shot up, Palmar pointed out.

The monetary rewards, such as royalties, mainly benefited the city governments, which used the money to build shiny new government buildings and tourist attractions, while dedicating very little to cover the needs of the local population, Palmar complained.

Nevertheless, the situation at Itaipú stands in contrast with the situation in other parts of the country, especially on the São Francisco river, where there is a national clamour for the river to be cleaned up and revitalised, and where there is only an incipient programme coordinated by the environment ministry.

Five large hydroelectric dams with a total combined output of 10,827 MW – equivalent to 77 percent of Itaipú’s production – harness the increasingly scarce water in Brazil’s semiarid Northeast.

The main portion of the river crosses the impoverished region, and besides the frequent droughts, the São Francisco suffers from sedimentation and pollution caused by human activities, such as deforestation along the riverbank, the dumping of untreated sewage, and agribusiness projects irrigated with water from the river.

The Itaipú hydrower complex, an example of bilateral energy integration that cannot go beyond the borders of Paraguay and Brazil. Credit: Darío Montero/IPS

By Marianela Jarroud
SANTIAGO, Oct 31 2013 (IPS)

Energy integration efforts in Latin America have been made in fits and starts, even though many clearly understand that the only way to solve the region’s energy shortages and high costs is by working together.

Experts who spoke to IPS agreed that the main difficulties in achieving energy integration lie in the differences between national energy supply systems. In the region there are countries with centralised state management and others with mixed public-private systems.

Other factors that affect integration are differences in fuel prices, uncertain availability of natural gas supplies, and socio-environmental conflicts over major energy projects such as mega-dams.

To move forward towards integration, they say, commercial and technical regulations must be adopted for a viable international market for electricity, to operate interconnected systems, harmonise national regulations, and coordinate planning for connected systems, in order to develop a regional market.

Common criteria for reliability standards, rationing priorities, and distribution of congestion pricing revenues also have to be defined.

The first in-depth study on these questions in Latin America was carried out in 1964, when the Commission for Regional Electricity Integration (CIER) was founded. It is currently made up of 10 countries, including the founders – Argentina, Bolivia, Brazil, Chile, Paraguay and Uruguay – as well as Colombia, Ecuador, Peru, Venezuela, and seven companies.

CIER has carried out more than 20 studies that have outlined the concrete possibilities for unifying the region’s power grids.

But Latin America is far from achieving energy integration, Oscar Ferreño, CIER international coordinator for generation, told IPS.

Among the factors standing in the way of integration are a lack of political will and the privatisation of a number of major power production and distribution companies and oil companies since the 1990s.

Ferreño pointed out that there is one interconnected area, among the founding members of the Mercosur (Southern Common Market) trade bloc – Argentina, Brazil, Paraguay and Uruguay (Venezuela recently became the fifth full member).

But he warned that “there is a natural barrier that is difficult to overcome: the Andes mountains.”

At any rate, several bilateral or multilateral initiatives for interconnection have been studied, and some of them could be implemented, he added.

One example is the electric power interconnection between Uruguay and Brazil, which involves a 420-km power line with a capacity of 500 MW and a high-voltage direct current converter station, that is to come onstream in mid-2014.

The Brazilian government is also discussing with Argentina and Paraguay the construction of a 321-km power line with a capacity of 2,000 MW to interconnect two binational hydroelectric dams: Yacyretá, shared by Argentina and Paraguay, and Itaipú, between Brazil and Paraguay.

The problem is that the Itaipú contract prohibits the sale of energy to a third country.

In the Andean region, meanwhile, two projects are still only on paper. One arose from a 2007 United Nations Development Programme (UNDP) study on the complementarities of energy resources in Bolivia, Chile, Colombia, Ecuador and Peru.

The other is the Andean Electric Interconnection, which would involve the five Andean countries and has the backing of the Inter-American Development Bank.

But the idea of establishing a regional energy network focuses on tapping the oil reserves of Argentina and Venezuela, the gas reserves of Peru and Bolivia, the hydroelectric systems of Chile and Brazil, and the region’s solar and wind power potential.

Ferreño said “energy integration is fundamental,” principally because of the variation in non-conventional renewable energies, like solar and wind power, which have a vast potential in Latin America.

“Wind can blow in the south at one point and not in the north, or it could be cloudy, so integration facilitates the homogenisation of the production of the different natural energies, which is essential,” he said.

The director of the TNS Latam consultancy, Fernando Meiter, agreed that “regional energy integration is still far off.

“It is impossible if there is no framework so that if one country has a surplus, it can be given to a neighbour. That’s basically the problem,” he said.

“Argentina has several gas pipelines to Chile and one to Uruguay, which are currently not in use. In the short term, I don’t think integration will be achieved,” Meiter said.

Argentina exported natural gas regularly to Chile until 2006, when it began to sell only small quantities because it had to cover its own domestic needs first.

Chile, even without resolving the question of the diversification of its energy mix, could turn to Bolivia, another large gas supplier. But there is constant diplomatic tension between the two countries over Bolivia’s long-standing demand for an outlet to the Pacific Ocean, which it lost to Chile in the 1879-1883 War of the Pacific.

Bolivia currently exports significant volumes of natural gas to Argentina.

According to the Latin American Energy Organisation (OLADE), regional energy consumption amounted to 1,073 terawatt hours in 2010 at high prices, both for residential and industrial uses.

Official figures indicate that in 2011, Chile was the country with the sixth highest prices for the industrial sector in the Organisation of Economic Cooperation and Development (OECD), at 154 dollars per megawatt hour.

Meiter noted that one of the benefits of energy integration is the ability to negotiate prices as a bloc.

“For example, if Argentina, Chile, Brazil and Uruguay could jointly purchase natural gas from any of the Arab producers, if they went together to negotiate volumes, the prices would come down,” he said.

In his view, the Andes are not an obstacle for integration, “because the infrastructure is already there. That means it’s a question of political will,” he said.

Test tubes in the biogas laboratory that Itaipú has established in its technology park in search of greater efficiency in the production and use of this energy source. Credit: Mario Osava/IPS

By Mario Osava
FOZ DO IGUAÇU, Brazil , Sep 3 2013 (IPS)

The massive Itaipú hydroelectric dam, shared by Brazil and Paraguay, has now become a model for the micro-scale production of an energy source that is not only clean, but also helps to reduce pollution and promote local development: biogas.

Preventing the pollution of the reservoir with organic waste in order to preserve the energy-generating efficiency of the hydroelectric plant is a key goal for Itaipú. Its main socio-environmental programme, Cultivating Good Water, comprises 65 actions for the protection of the Paraná River Basin 3, the area affected by the dam on the Brazilian side, in the western part of the state of Paraná.

Producing biogas from animal manure fulfils this pollution-fighting function. But it also reduces emissions of greenhouse gases and provides a source of income for local farmers, explained Cícero Bley, superintendent of Renewable Energies at Itaipú Binacional, in an interview with Tierramérica.

The prospect of incorporating the energy business into his farming activity was an exciting one for cattle farmer Gedson Vargas. His enthusiasm probably played a decisive role in his rise to the presidency of the Coperbiogás cooperative, despite the fact that he was a relative newcomer among the traditional inhabitants of the Ajuricaba River valley, many of whom are descendents of German immigrants.

In 2007, at the age of 51, and with three young children, Vargas realised a long-held dream by purchasing 17 hectares of land in the valley for the equivalent of around 100,000 dollars. “I have always lived in the countryside,” he noted, but he endured five years as a milk vendor in the city in order to save up the money to buy his plot of land.

“I started out with 12 borrowed cows, but I grew, and now I have 40, plus 12 calves,” he told Tierramérica. With these, he produces enough biogas for household consumption as well as a surplus supply. But he is limited by the small size of his current biodigester, a mere 10 cubic metres. He hopes to obtain a larger one through Itaipú, which might be one abandoned by a neighbour.

“It’s a lot of work, but it was the same before, since we had to clean the manure out of the stables,” he said. Now there are environmental benefits, the foul smell and mosquitoes are gone, and the river and a nearby lagoon are cleaner.

Moreover, after the biogas is extracted, what remains of the manure can be used as bio-fertiliser, “which improves the pasture land, and it’s free,” he remarked. The fact that he no longer needs to buy chemical fertilisers adds up to savings of around 150 dollars a month.

The only crop that Vargas grows is corn, on 10 hectares of his land, and he takes advantage of the entire plant, including the kernels, husks and stems, which he stores and uses to feed his cows during the Southern hemisphere winter. The recent purchase of a tractor is proof of how well business is going.

Not even the setbacks faced by the cooperative can dampen his enthusiasm. It all began in 2009 with the Agro-Energy Cooperative for Family Farmers in the Ajuricaba River Basin, later formalised as Coperbiogás. There were originally 41 families involved, but eight dropped out or left the valley.

For more than a year everything has been ready to generate electricity at the biogas micro thermoelectric plant, built with donations from Itaipú on land allocated by the municipal government of Marechal Cândido Rondon. The sale of electricity will provide additional income for the cooperative’s 33 member families.

The micro power plant has the necessary inputs from the family farm biodigesters connected to it by pipelines, but its operation is awaiting a decision from Compañía Paranaense de Energía (COPEL), the public power company in the state of Paraná that would purchase and distribute the electricity.

An alternative is direct sale to an agricultural cooperative, Cooperativa Agroindustrial Copagril, in Marechal Cândido Rondon, which has expressed interest.

But the “lungs” of the micro power plant, the large plastic tank that stores the biogas, already has leaks, as evidenced by the foul odour. It will need to be replaced with a more resistant and larger tank.

In addition, it will be necessary to install 1,200 metres of pipes and ensure a regular supply as well as reserves. The investment required is greater than what the cooperative can afford, Vargas acknowledged.

Technicians from Itaipú estimate that the cooperative members have a combined total of 1,000 cows and 3,000 pigs. The resulting 15,800 cubic metres of manure annually would generate 266,600 cubic metres of biogas and 445,000 kilowatt-hours of electricity, enough to supply 2,200 households.

For now, Coperbiogás offers the services of a small grain dryer, which uses biogas to generate hot air flows.

The Ajuricaba initiative plays a key role as a model for family farmers, who must work as a group in order to make an energy-producing enterprise like this feasible. The Uruguayan public power utility, for example, as already decided to replicate the project in its own country.

The experience could also be extended throughout the western region of Paraná itself, where 80 percent of rural landholdings cover at least 50 hectares, and there are 26,000 family farmers and significant agro-industrial production of cows, pigs and poultry, said Bley, an agronomist and recognised expert on alternative energy.

But the pioneer in the commercial production of biogas is a medium-sized enterprise. Granja Colombari, a farm with around 4,000 pigs in the municipality of São Miguel do Iguaçu, has been selling biogas electricity to COPEL since 2009.

Other biogas-powered thermoelectric plant projects are also underway, such as one on a large dairy farm and three being developed by a large commercial agricultural cooperative.

For more than four decades, electric power generation has been highly concentrated in the pursuit of greater efficiency, and Itaipú is a prime example of this. But this model has run its course, leading to the need for the incorporation of distributed and decentralised generation. Micro power generators will play an important role, because in addition to producing energy, they also contribute to local development and environmental improvement, stressed Bley.

The decision made by Itaipú to pursue this path “is not a publicity stunt, but rather the result of a deep conviction,” he said. That is why last year, in partnership with the United Nations Industrial Development Organisation (UNIDO), it created the International Centre for Renewable Energies, the first in the world with an emphasis on biogas, where Bley is the general director.

Rural economic activity is boosted with the income from energy generation and the “biogas economy”, including its supply, service and knowledge chains, but urban sanitation systems can also make use of wastewater, a significant source of gas, he added.

The biogas initiative in Ajuricaba, for example, has helped to foster a local small industry. Its blue biodigesters and black storage tanks, which can be seen next to the stables, are manufactured by BioKohler, a company incubated by Itaipú.

The new entrepreneurs embarked on this innovative venture 10 years ago on their father’s milk farm, in the same municipality of Marechal Cândido Rondon, Paulo Kohler told Tierramérica. They began by producing plastic biodigesters, and then his brother Pedro invented the fibreglass digesters that are used in Ajuricaba in three different sizes, ranging from 10 to 40 cubic metres.

Now they are working on producing concrete biodigesters, which are larger and more expensive, adapting stoves for biogas use, and improving the storage tanks. “We are just surviving,” but the biogas market is promising, said Paulo.

* This story was originally published by Latin American newspapers that are part of the Tierramérica network.

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