Diesel oil will continue to be the main material for power generation along with liquefied natural gas, wind and solar energy.
Total capital to develop power generation and a transmission grid for Con Dao will be VND2 trillion (US$95 million).
There will be two other power investment projects: Con Dao Wind Power Plant with capacity of 4MW and a Solar Power Plant with capacity of 5MW, to be built for a total of VND645 billion ($31 million).
"Power plays the most important role in developing tourism, production and other services on Con Dao island," Nguyen Van Dung, deputy chairman of Con Dao island People's Committee, was quoted as saying in Tin Tuc (News) newspaper.
Power supply on the island has met only half of demand, with two power-generating mills run by diesel oil. Many big and luxury hotels have their own power generators.
"If local residents develop more tourism services with mini hotels and hostels, we won't be able to meet power demand," Dung said.
All households on the island now have access to power, with 48 per cent used for daily usage and 31 per cent for tourism and services, with nearly 1,900 customers.
Diesel prices account for 85 per cent of the power prices on Con Dao island.
One litre of diesel can generate 3kW at a price of VND15,000 (0.7 cent) but local residents pay the same price as the mainland, VND2,000 for 1kW.
"Therefore, the more we generate, the more we lose," Doan Van Tranh, director of Con Dao power, said.
Last year, the power sector on the island lost VND46 billion ($2.1 million) compared to the average loss of VND33 billion ($1.6 million).
Kim Thi Anh, owner of Tri Ky restaurant, who has lived on Con Dao for 30 years, said: "In the past, my restaurant had to pay around VND15-17 million for power each month. Since we can pay the same price as the mainland, we only pay around VND5 million each month."
"The quality of power is better than before and if we lose power, it only lasts five to 10 minutes," she added.
The Con Dao power sector has set a goal this year to generate 11 million kWh, an increase of six per cent compared with 2014.