Power to the Project Movers

By Thomas Timlen

Discussions related to China’s Belt and Road, or BRI, initiative generally focus on regional transportation infrastructure and the respective segments of the supply chain; roads, rail, tunnels and bridges linked to seaports and the multiple logistics hubs along the way. Less attention is given to the sustainable renewable energy-generating initiatives associated with the BRI.

A project in Laos, the Nam Theun 1 Hydropower project, is one such BRI initiative developed alongside the China-Laos Railway, both falling within the Lancang-Mekong Cooperation Economic Development Belt.

The Nam Theun 1 Hydropower project, one of the largest hydropower projects under construction in the world, is an ambitious US$1.3 billion joint venture involving three partners; Phonesack Group with a 60 percent stake, Egco with a 25 percent stake, and Electricite Du Laos (EDL) with a 15 percent stake. It is designed to bring additional renewable power to Laos and neighboring Thailand. The project, lasting 56 months, involves the construction of a dam of 4 million cubic meters, which will power a hydroelectric power station with an installed capacity of 650 megawatts and design discharge of 514 m³/sec. The latest forecasts call for commercial operations to commence in August.

CMC, in a joint venture with two of the largest construction companies in Thailand and Vietnam, chose Italy’s ATB Riva Calzoni as a partner for the project, signing an engineering, procurement and construction contract for the entire hydro-mechanical scope of work of the dam under construction in the province of Bolikhamxay, Laos.


Challenges from the Start

The hydroelectric plant, built on the Nam Kading river, a tributary of the Mekong, will produce power that will be distributed by Edl-Electricite’ du Laos. Power will be exported to Thailand on behalf of the Electricity Generating Authority of Thailand.

From the start, heavy-lift contractors faced significant challenges with the delivery of some construction equipment from abroad affected by the pandemic, resulting in some equipment being brought in by air transport before Laos closed its borders. With a series of lockdown measures in Laos that caused difficulties in equipment and material supply, contractors had to actively coordinate with project managers and relevant government departments to make sure that construction could be carried out smoothly.

As a lead contractor on the project, ATB Riva Calzoni’s hydropower experience gained from projects such as the Ituango project in Colombia and the Nachtigal project in Cameroon was put to good use.

For the Nam Theun 1 Hydropower project, a major challenge was the transportation of 50 pipe sections, known as penstocks. A penstock is a sluice for directing the flow of water to the hydroelectric station. For this project, each penstock section measured up to 10 meters in diameter with a weight of up to 50 tonnes. These had to be moved from their onsite fabrication site into position within the dam walls. The fabrication site was located 3 kilometers from the installation site and the penstocks had to be moved across a route that included several steep gradients and through a 400-meter tunnel which proved to be an extremely tight fit.

ATB Riva Calzoni’s hydropower site manager Gerardo Ruotolo found the tunnel to be the most daunting challenge, which benefited from project specialist’s Mammoet’s expertise. “A significant challenge in which Mammoet assisted ATB Riva Calzoni is related to the Adit 1 tunnel. A section of this access tunnel had a restriction, due to civil works constraints, which made it difficult to transport the 10 meter diameter penstock. Mammoet solved this issue allowing the passage of the penstock pipes to the work front.”

Ruotolo further explained that the logistics aspects of the project on-site, including the location of the penstock fabrication yard, the route for moving the penstocks to the access tunnel and the tunnel dimensions were all defined at an earlier design stage by the civil works designer and ATB Riva Calzoni’s technical department. Mammoet experts were brought in at a later stage, once all the above aspects had been defined, to develop the most suitable solution based on the actual site conditions.

Once online, Nam Theun 1 will deliver clean energy for more than 500,000 homes and play a key role in the region’s energy transition. Building a hydropower plant on this scale is a complex task, with components needed at their installation location intact and on time if the schedule is not to be impacted.


Calling on Specialists

Any delays in navigating the route or any damage to the pipe sections would have serious repercussions for the project schedule. This was another factor that led ATB Riva Calzoni to enlist specialist support from Mammoet to ensure this risk was minimized and work was kept on track.

Ruotolo explained that the company “recognized that the expertise of a heavy transportation specialist was needed to handle the movement of the pipe sections from the fabrication yard.” He added that “the knowledge and capabilities Mammoet brought have been extremely important in avoiding any significant issues in this high-risk part of the project.”

The Nam Theun 1 Hydropower project is the first project in which ATB Riva Calzoni and Mammoet have cooperated, although it likely won’t be the last. “For sure,” Ruotolo said, “there is interest in cooperating with Mammoet in future projects, given the positive experience faced in Nam Theun 1 Hydropower project.”

Comprehensive planning was key to the project’s success. Mammoet recognized that while the weights involved were not particularly challenging, the restricted dimensions of the tunnels required a detailed plan and highly skilled self-propelled modular transporter, or SPMT, operators to execute.

Mammoet’s extensive in-region experience proved crucial, ensuring that necessary permits were obtained for the 3 kilometer journey across varying gradients and qualities of terrain. Preparatory work was then performed for the sizeable cargo to be ready for transportation via 16 lines of SPMT.

Already a formidable job, it was made all the more challenging by adverse weather conditions. Heavy rain significantly increased the risk of the oversized but relatively lightweight cargo causing the SPMTs to slip or lose traction. This again highlighted the importance of Mammoet’s local experience. Having worked under similar conditions in other countries in the region, the team was able to identify the hazards presented by the rain and to plan ahead to avoid accidents.


Tunnel Vision

Mammoet’s skills were also put to the test in navigating the restricted space of the tunnel. “When moving large components in such a confined space there is a high risk that either the item or the surrounding tunnel will be damaged,” Thanapon Varintree, sales manager at Mammoet, said, “which in turn can lead to prolonged project delays while this is put right. At Nam Theun this was made even more difficult by heavy rain increasing the risk of the cargo slipping when moving up or downhill.

“Using SPMTs and experienced operators gave us the ability to be very precise in how we moved through the tunnels, making small adjustments in direction or speed where necessary to avoid damage.”

Mammoet completed the transportation of all 50 components within the required time frame, overcoming the elements and demonstrating a real test of close SPMT control to ensure that construction of Nam Theun could continue as planned. The hydropower plant project is in the final stages of development, with all the construction work being carried out in line with international standards.

As Laos is pursuing plans to build dozens of hydropower dams on the Mekong River and its tributaries, additional opportunities are on the horizon for the contractors engaged with their planning and construction as well as for the heavy-lift providers needed to move the massive components in place.

Ruotolo said that ATB Riva Calzoni is working on several hydropower projects on all five continents, as the contractor for steel penstocks and hydromechanical equipment. “In particular, according to our experience, hydropower has a significant role in renewable energy development in Asia and Africa. In the other continents, hydropower development is driven by pumped storage hydropower projects which are considered the most important energy storage technology and currently guarantees 90 percent of energy storage capacity of the world.” 


Thomas Timlen is a Singapore-based analyst, researcher, writer and spokesperson with 31 years of experience addressing the regulatory and operational issues that impact all sectors of the maritime industry.

Image credit: ATB Group