China stocks closed at an eight-month high on Tuesday, while Hong Kong shares extended gains to a multi-year peak, driven by construction and power firms after work began on a major dam project in Tibet,

The investment is set to benefit hydropower plant and grid equipment makers, but some analysts warn that market enthusiasm may wane soon.

China has started construction of the world’s biggest hydroelectric dam, a project that’s set to be far larger than the Three Gorges Dam — already the world’s biggest single source of green power — and more expensive than the International Space Station.