The latest monthly study from Medellin-based wholesale electric-power grid operator XM finds that hydroelectric generators now account for 85.7% of all national power generation – confirming Colombia’s enviable status among the “greenest” power generators on Earth.

What’s more: Once Medellin-based EPM resolves what today is looking more like a temporary engineering problem with its under-construction, 2.4-gigawatt “Hidroituango” hydroelectric dam in Antioquia, hydropower’s dominance in Colombia is likely to continue for decades to come.

The city of Medellin is the 100% owner of EPM -- and the US$5 billion “Hidroituango” project is expected to help to continue delivering about 25% of the city’s annual revenues, when the current tunnel-and-dam engineering challenges are overcome -- as is now expected -- over the coming months.

Meanwhile, EPM announced June 13 that it has hired Imperial College (London) geology expert Nicolas Barton -- one of the world's top authorities on rock stability associated with mountains, dams and tunnels -- to investigate the current status and outlook for the rock massif and tunnels above and adjacent to the Hidroituango dam. EPM general manager Jorge Londoño de la Cuesta previously has stated that existing geological studies and EPM's continuous measurements employing sophisticated equipment indicate a very small possibility of any major collapse of the massif. 

Aside from hydropower -- 99.17% of all renewable power delivered to the Colombian grid -- other relatively negligible renewable-power generators here include bagasse-based thermal power generation (0.75%), wind-turbine generation (0.06%) and photovoltaic power (0.02%), the new XM study shows (see chart, above).

Bagasse-fired thermal power generation (using sugar-cane crop residue) fell 37% month-on-month (May 2018 versus April 2018) while biogas-fired thermal power generation plummeted 66%, the study shows.

“The source of [renewable] energy with the greatest contribution [to the national power grid] was the hydraulic generation with 99.17%, equivalent to 158.47 GWh-day [gigawatt-hours per day], a decrease of 0.45% in relation to April of 2018, and solar power, with a contribution of 0.02%, equivalent to 0.03 GWh-day, saw a decrease of 6.33% in relation to April of 2018,” according to XM.

“The total generation with non-renewable resources (fossil fuel) for the month of May was 26.70 GWh-day, a growth of 7.49% compared to April 2018.

“By subtype by source of energy, we found that natural gas was the largest contributor [in fossil-fueled thermal-power generation] with a 72.25% share, equivalent to 19.29 GWh-day, 10% more than that reported in April 2018. The greatest decrease was presented by liquids [diesel and fuel-oil] with 9.30%,” XM reported.

“For Colombia, it is very positive to have a diversified energy matrix, adaptable to climate changes, thereby contributing to preserve the provision of electric power service in conditions of reliability, security and economy,” added XM’s National Dispatch Center manager Jaime Alejandro Zapata Uribe.