USA: The United States faces nine major supply chain challenges that could delay hydropower rehabilitation projects, according to a new report from the National Laboratory of the Rockies (NLR).
The study focuses on the supply of large power transformers (LPTs) used in hydropower facilities. These custom-built units raise the voltage of electricity generated by turbines, allowing power to be transmitted efficiently across long-distance networks.
According to the report, a typical 100 MVA large power transformer can take around 2.5 to three years to procure, while lead times for extra-high-voltage units may extend to five years because of limited global manufacturing capacity.
Cost is also a growing challenge. Transformer prices were reported to have increased by around 80 % in 2025 compared with 2021 levels, with some units costing up to $10 M.
The report also points to heavy import dependence. More than 80 % of US LPT demand is met through imports, while domestic production remains constrained by bottlenecks in materials and components such as grain-oriented electrical steel, copper, bushings and on-load tap changers.
Hydropower projects face an additional challenge because many dams are located in remote or difficult-to-access areas. Transporting large transformers requires specialised vehicles, route planning, permits and heavy-duty equipment.
The findings could support future policies, incentives and investment aimed at strengthening domestic transformer manufacturing and improving supply chain resilience.
Hydropower currently provides more than 6% of US electricity generation, making transformer availability an important factor in maintaining and upgrading this part of the power system.
Source: Interesting Engineering
