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Preformed Windings

Preformed Windings are thought leaders in the design and manufacture of High Voltage (HV) diamond coils. Based in England and founded in 1967, the company specialises in partnering with service organisations, including original equipment manufacturers and end users to support hydro refurbishment projects. These partnerships significantly increase the output of generators and reduce maintenance requirements.

As an independent manufacturer of HV coils, Preformed Windings has a single focus: developing specifications and manufacturing processes that ensure cutting-edge technology delivers critical benefits. Independent status allows the firm to carry out significant R&D in collaboration with leading original equipment manufacturers and insulation suppliers, building long-term partnerships based on trust.

Preformed Windings specialises in projects where quality is key, and specific requirements such as output increases are required. An example is the Holter Dam project in North America where output improved by 42%.

The manufacturer believes that hydropower is key to net zero goals. In regions such as North America and Europe where much of the installed hydropower is older than 30 years, and the options to build new hydro are limited, there is a huge opportunity to modernise the fleet.

Preformed Windings believes in knowledge sharing with partners, end users and the wider industry to ensure the application of modern HV coil technology for improvements in the hydropower industry.

James Stevens, Global Sales and Marketing Director & ESG Champion, stated that:

“Building long term partnerships based on trust, having belief in thought leadership and cutting-edge R&D, and with a grounding in ESG, we believe hydro can become even more sustainable and contribute toward a greener future. Preformed Windings is very proud to be members of IHA and look forward to collaborating with likeminded individuals and organisations.”

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