Sustainable Firm Power Supply in Colombia Through Hydropower

Electrical power demand in Colombia projected at 10,0 GW by April 2019 (end of the dry season) is covered by an 17,2 GW installed capacity. Nevertheless, since about 70% of this capacity is hydroelectric and the country is periodically subject to low rainfall during El Niño episodes, available hydro generating power can be severely reduced by low reservoir levels and low river flows on run off river plants. In addition, thermal power stations contribute proportionally less firm power than required by the supplied load firm energy. Firm power availability is projected only at 11,2 GW, considering minimum reservoir levels and minimum contribution from run of river plants.

Expansion of the power generating plant, to supply energy load growth is envisioned with a growing share of sustainable eolic and photovoltaic generation, with almost no contribution to firm power, and new coal fired power stations falling short of a proportional contribution to firm power as required by the load, reducing the available 11% margin. As a result, this paper discusses the opportunity window that is opening for the sustainable supply of the required extra firm power by increasing the installed capacity of existing hydropower stations, adding reservoirs to existing run of river plants and planning of new hydro power stations with lower plant factors. These are less costly than battery storage and with the added advantage that generation can be offset to higher priced hours.