LHASA, Sept. 28 (Xinhua) -- Stable electricity supply has reached 70 percent of Tibet's population as grid upgrades in the region conclude.

Sources with the State Grid Corporation said the region's main grid has been extended to 62 out of 74 counties and urban districts in Tibet Autonomous Region, covering 1.6 million people living in rural areas.

As of the end of 2011, power had reached the last 520,000 rural Tibetans living without electricity, but the supply remained unstable as power in some places were provided by small hydro stations and blackouts were common during the winter dry season.

In 2016, Tibet began the latest upgrade of rural electricity, extending the main grid to previously unreachable areas. The upgrade is estimated to cost about 11.9 billion yuan (1.83 billion U.S. dollars).

The authorities have set a target to provide stable electricity to 97 percent of Tibet's population by 2020, and the remaining 3 percent will use solar panels or small hydro-stations.