In June 1994, HINISA was granted a thirty-year concession for the generation, sale and commercialization of electricity from the Nihuiles hydroelectric system (the “Los Nihuiles System”). Located on the Atuel river, in the Province of Mendoza, the Los Nihuiles System has an installed capacity of 265.2 MW, which represents 1.0% of the installed capacity in Argentina, and is composed of three dams and three hydroelectric power generation plants (Nihuil I, Nihuil II and Nihuil III), as well as a compensator dam. The Los Nihuiles System covers a total distance of approximately 40 km with a height differential between 440 m and 480 m. From 1990 to 2009, its annual average generation was 915 GWh, with the highest level of generation (1,250 GWh) reached in 2006 and the lowest level (681 GWh) recorded in 1999.

HINISA’s revenues are composed of energy and capacity sales. Total revenues for the twelve-month year ended December 31, 2009 were Ps.155 million, corresponding to a net generation of 854 GWh, 3.6% lower than in 2008, with a hydraulic contribution of 954 Hm, 12% lower than in 2008.

HINISA made 72% of its sales in the spot market. Availability of the power plants reached 94.1%.

The following chart shows certain relevant statistical data on Los Nihuiles:

		2005	2006	2007	2008	2009
	Net Generation (GWh)	1.028	1.250	1.053	886	854
	Energy Purchases (GWh)	415	434	395	370	308
	Total Energy Sales (GWh)	1.443	1.684	1.448	1.256	1.162
	Average Price (Ps. / MWh)	59,6	76,5	98,5	121,3	133,5
	Average Gross Profit (Ps. / MWh)	26,0	36,0	46,2	54,1	60,3
Note: Gross Margin before amortization and depreciation charges.