Sguards armed with patrols patrol an anonymous warehouse on the outskirts of Ciudad del Este. Perched on the triple border where Paraguay meets Brazil and Argentina, the melting pot city is often associated with smuggling, cartels and drugs.
But inside, a new hot commodity is accumulating from the second. Dozens of dismantled CPUs and Internet-connected circuits move away into the darkness, the LEDs flash, adding subtropical warmth.
These are just some of the approximately 20,000 units scattered throughout the city, mainly for the mining of Bitcoin and Ethereum cryptocurrencies in a sector that has sprung up from one day to the next.
Behind the boom is the monolithic dam of Itaipú that the country shares with Brazil, which extends across the Paraná River, just north of the city. It is the most powerful hydroelectric plant in the world and its abundant availability of energy makes Paraguay an ideal environment for bitcoin mining.
Itaipú is enriching some of them. But the increasingly complicated calculations that underlie bitcoins require increasingly powerful computers and cooling systems, which consume more and more energy.
And many argue that Paraguay could better use its abundant hydropower to help the quarter of the population currently living in poverty. According to World Bank data, Paraguay has the highest level of inequality in land ownership in the world.
"Some people have become multimillionaires," said Gregorio Bareiro, whose first contact with the bitcoin industry arrived in September, when his conditioning business started to provide bitcoin investors with a cooling system that from it that involved wet cardboard and industrial fans.
Now it hires 750 computers owned by it – mainly Brazilians, Europeans and North Americans – employing a dozen employees and plans to install mobile mines in portable trailers.
"Paraguay today is the only place where there is an abundant energy," Bareiro said enthusiastically. "We can become the center of global bitcoin mining".
Paraguay owns half of Itaipú's output. But its few factories and the squeaking national network are barely able to absorb all this power, and is forced to sell the huge surplus in Brazil – well below the market price, experts say.
This surplus of power means that its internal energy prices are around 5 cents per kilowatt hour – just a fifth of those of the giant next door – causing an influx of factories and foreign-owned investors in recent years.
Paraguay should open the red carpet in addition to cryptocurrency miners, Bareiro said. The entrepreneur thinks that using the power of Itaipú to further cut energy prices, the owners of the 150,000 units currently in China may be tempted to stamp in Paraguay.
"In 10 years, it would generate enough money to pay off Paraguay's foreign debt," he suggested. "With our resources, we should have electric helicopters, drones for the transport of goods …
"We have found a way out for our country," he added. "The best chance we have is not to sell our energy in Brazil but to invest in cryptocurrency".
Not everyone is convinced that energy commodity is the way to go.
A growing coalition of Paraguayan politicians, academics and businessmen wants the country to embark on profound negotiations with Brazil on the dam's financial dividends – by 2023 – to further spread the benefits of Itaipú's generosity.
According to Gerardo Blanco, director of a research team on energy at the Universidad Nacional de Asunción, "2023 represents a unique opportunity for Paraguay".
A study of the group suggests that directing the energy currently sold abroad in national production could generate 2 million jobs and quadruple the GDP of Paraguay, transforming the fate of one of the poorest countries in South America.
"This would be a quantum leap that will have enormous implications for society, the economy and even our culture," added Blanco.
Also Cristine Folch of Duke University suggested that Paraguay could provide clean energy data centers for software giants like Google, Apple and Facebook, and become a regional hub for lithium battery production.
If now the country takes advantage of Itaipú, while its population is still small, "it could put Paraguay on the edge of the technological frontier," he told the Guardian.
Miguel Carter, a Paraguayan development expert, suggested that by negotiating a fairer price for his energy, Paraguay could better finance hospitals and schools and resurrect the rusty railways of Paraguay.
According to Carter's calculations, Paraguay was defeated by Brazil in negotiating the 1973 Itaipú treaty – signed between two dictatorships – and deceived by a surprising sum of $ 57.7 billion in lost revenue.
In 1979, the Brazilian military regime assassinated its ambassador in Paraguay to prevent him from disclosing the billions of dollars of bribes involved in the construction of Itaipú, it was officially confirmed in October.
"When I saw the numbers, they burst into tears," Carter told the Guardian. "I know many stories of Paraguayans going to the hospital and losing their loved ones … there would be lives saved, children with decent education, you could have had a different country."
A spokesperson for the Brazilian Foreign Ministry rejected the idea that Paraguay was defrauded, indicating the previous Brazilian concessions and stating that the country had guaranteed and guaranteed the shared debt used to finance the construction of Itaipú.
The president-elect of Brazil, Jair Bolsonaro, who will take office in January, is likely to prove a ferocious opponent in the negotiations.
But some dare to hope that the energy resources of Paraguay could soon be exploited to help them.
Several hours north on the highway, and one hour on a dirt road, 43 indigenous families of Ava Guaraní from the Tekoha sauce community live in heaps of shacks, sandwiched between soybean fields and a polluted trail of Paraná, near the border with Brazil.
They lack clean water, health care and electricity. The chemical drain from the neighboring fields has given many complaints about the skin.
They came back here in 2015, having been forced to abandon their land by flooding the dam rising at the end of the 70s.
Soon after, a police raid ripped their crops and burned their homes, school and church. "If there is another eviction we will stay and die," said Amada Martínez, a community leader. "Because we have nowhere else to go."
Now they are in talks to secure the title of a fraction of their ancestral territory. "People think it's a marvel," added Martínez. "But the damage that Itaipú has caused to our people … behind the story, there is suffering."