Hydro giants: Good or evil?
In the never-ending cycle of news predicting our species’ annihilation, it’s perhaps comforting in some ways to note that the pursuit of cleaner ways to generate energy are still at the forefront of government agendas. Perhaps we can discount the US from that list of governments but, broadly speaking, most are pursuing more environmentally friendly methods of generating power.
After recent reports that we could be heading into a “hothouse” stage of runaway global warming you’d certainly hope for some radical thinking in this arena, and a humungous dam built in the rainforest to capture hydro-power could potentially tick that box for you.
The Belo Monte dam, currently being constructed on the “Big Bend” of the Xingu river in the Brazilian Amazon is certainly an impressive and awe-inspiring structure that captures the imagination and attention of the public.
Originally conceived in the 1970’s the dam finally saw a start on its construction in 2011 and some of the statistics about the build are staggering. Costing R$30 billion (£5.8 billion), Belo Monte required an army of 25,000 workers working round the clock to excavate an enormous 240m cubic metres of soil and rock. It also required three million cubic metres of concrete and the diversion of 80% of the river’s flow through 24 turbines.
Despite the fact that the dam hasn’t even been completed it already provides 11,233 megawatts of energy to over 60 million Brazilians and once completed will be the largest hydroelectric power source in the Amazon and the 4th largest on the planet.
By most standards, in terms of renewable energy that’s a pretty impressive output and represents nearly 15,000 megawatts of energy that doesn’t need to be generated by fossil fuels, however, there are some serious misgivings about the wider implications of constructing such a monster in the middle of the forest.
Detractors of such enormous projects pointed out that nearly 100,000 construction workers descended into the local area over a near ten year period meaning that resources were seriously stretched in an area nowhere near used to having to provide for such a population. This population, however, is not sustainable as once the project is finished up to 90% of that workforce will be leaving.
There is, of course, the real cost of indigenous people living on the river banks and near to the river higher upstream to where the dam is being built. Their villages and homes have effectively been demolished with rising water levels making their homes now uninhabitable.
Greenpeace has linked illegal deforestation in indigenous reserves – more than 200km away – to the construction of the project, with the wood later sold to those building the dam.
One further issue with dams of this stature is that they actually release a significant amount of methane gas which is generated by composting plant life and trees below the surface of the increased water levels. Whilst methane does not stay in the atmosphere as long as carbon dioxide (methane stays on average 19 years) the warming effects tend to be much worse.
It could be said that over its lifetime that the deforestation and methane contributions of the Belo Monte may even eradicate its environmentally friendly energy generation.
In an increasingly complicated field of generating clean energy, the Belo Monte only serves to highlight the issues that we must face with increasing urgency.