Change in RusHydro's interest in Sakhalin Energy C

September 21th, 2012

Change in RusHydro's interest in Sakhalin Energy Company

JSC RusHydro announces that following the registration of the additional share issue by Sakhalin Energy Company (JSC SEC) RusHydro's interest in JSC SEC has decreased.

The Federal Service for Financial Markets has registered report on additional issue of JSC SEC shares on September 20, 2012. This has led to reduction in the stake held in JSC SEC by RusHydro both directly and indirectly (via RusHydro's subsidiary JSC RAO of the East).

The stake in JSC SEC held by RusHydro directly has reduced from 17.7723% to 12.4385%.

The stake in JSC SEC held by RusHydro indirectly, via RusHydro's subsidiary JSC RAO of the East has reduced from 35.04374% to 24.5264%.

Charter capital JSC SEC consists of common voting shares only.

For more information:

JSC RusHydro, Investor Relations Department

Tel. +7 (495) 225-3232 ext. 1319, 1394, 1607

[email protected]

DISCLAIMER

The information in this press release may contain projections or other forward-looking statements regarding future events or the future financial performance of RusHydro. One can identify forward-looking statements by terms such as "expect," "believe," "anticipate," "estimate," "intend," "will," "could," "may" or "might," the negative of such terms or other similar expressions. We wish to caution you that these statements are only predictions and that actual events or results may differ materially from these statements.

We do not intend to update these statements to reflect events and circumstances occurring after the date hereof or to reflect the occurrence of unanticipated events. Many factors could cause the actual results to differ materially from those contained in our projections or forward-looking statements, including, among others, general economic conditions, our competitive environment, risks associated with operating in Russia and rapid technological and market changes in our industries, as well as many other risks specifically related to RusHydro and its operations.