Yangyel Lhaden

After more than three years of inactivity, one of the two wind turbines in Rubesa is now operational, while the other remains non-operational due to the pending arrival of parts.

The parts required for the non-operational wind turbine are expected to arrive by April.

The pair of turbines was inaugurated in 2016 as part of a pilot project to demonstrate the technical feasibility of generating wind power in the country and to enhance energy security by diversifying energy supply through alternative renewable energy technologies.

The project, which cost Nu 177 million, was funded by the Asian Development Bank.

When both turbines were functional, the project generated around Nu five million annually.

Connected to the national grid, the turbines, when operating at full capacity, can supply energy to approximately 300 households.

Until December 2020, the two turbines generated 4.82 million units of electricity, earning an income of Nu 24.566 million.

On average, the turbines produced 1.2 million units of electricity annually.

The wind turbines are operated and maintained by Druk Green Power Corporation (DGPC).

The cost of restoring the wind turbine is estimated at Nu 16 million.

The non-operational turbine has two major issues—a critical part called the IGBT filter module, used to control electricity, and the inverter module are completely damaged.

Additionally, an unusual sound from the gearbox suggests a mechanical fault that needs attention.

These issues were confirmed by Arudhra Wind Energy Pvt Ltd. and ABB India during their attempts to repair the turbine.

After the arrival of the replacement part, the IGBT filter, Arudhra Wind Energy Pvt Ltd. will work on restoring the turbine.

The operational turbine was repaired and restored to working condition after several key fixes.

A damaged blade was repaired on-site by Arudhra Wind Energy Pvt Ltd., following the original manufacturing process. ABB India replaced the controller unit and its software, while Komaihaltec Inc. from Japan, the original supplier, helped restore the turbine’s control system, known as the SCADA system.

According to the Renewable Energy Management Master Plan (2016), Bhutan has the potential to generate 12 gigawatts (GW) of solar energy and 760 megawatts (MW) of wind energy.

However, only 600 kilowatts (kW) of wind energy has been harnessed so far through the Rubesa wind farm. This means that the 600 kW currently produced represents only 0.079 percent of Bhutan’s total wind energy potential.

A Department of Climate Change official said that the Rubesa wind turbine project was a pilot initiative, and the lack of capacity within the country delayed restoration efforts.

The official said that engineers who were involved during the turbines’ initial setup and commissioning had since left the project, which further hindered early restoration, adding that the experience gained from this pilot project would be invaluable for future large-scale wind energy projects.

In the 13th Five-Year Plan, Bhutan aims to strengthen energy security by developing 500 MW of alternative renewable energy by 2029 and increase it to 1,000 MW by 2034.

The plan also includes implementing a 23 MW wind power project by the end of the 13th Five-Year Plan.