The 14GW Itaipu plant on the border of Brazil and Paraguay last year produced its highest ever annual output, reported the binational plant operator.

Itaipu generated almost 94,685GWh of electricity in 2008, which is 1.3% higher than the previous highest output, achieved in 2000. However, the plant had 20 generating units installed last year to take advantage of good hydrology on the Parana river compared to only 18 units in 2000.

Itaipu operated with 18 units between it commencing operations in 1991 to the third quarter of 2006 when the 19th turbine-generator was installed. The last unit was added in mid-2007. Typically, the plant is operated with all but two of the 715MW vertical Francis units running.

Output in recent years was averaging about 90,000GWh, rising from 2006 and the plant operator now expects production to be able average approximately 95,000GWh.

The output last year delivered a 19% share in the Brazilian market, which was no change on 2007. However, the share is down on the 26% share enjoyed in 1995 and 1996, shortly after the plant became operational. In 2000 Itaipu held a quarter of the Brazilian market.

In the third quarter last year, Brazil looked to further binational co-operation through a pact with Argentina to investigate additional hydroelectric schemes on the Uruguai river in the border region, especially for the Garabi scheme.

Also on the Parana river in the 1990s, Argentina developed the 3200MW Yacyreta project with Paraguay. Argentina also has a binational project with Uruguay – the 1890MW Salto Grande scheme.