--- title: "Gafr Hydro, Nant Peris" id: "5868" type: "post" slug: "gafr-hydro-nant-peris" published_at: "2026-02-06T09:20:46+00:00" modified_at: "2026-02-06T09:21:25+00:00" url: "https://dulas.org.uk/gafr-hydro-nant-peris/" markdown_url: "https://dulas.org.uk/gafr-hydro-nant-peris.md" excerpt: "[fusion_builder_container type=\"flex\" hundred_percent=\"no\" hundred_percent_height=\"no\" min_height_medium=\"\" min_height_small=\"\" min_height=\"\" hundred_percent_height_scroll=\"no\" align_content=\"stretch\" flex_align_items=\"flex-start\" flex_justify_content=\"flex-start\" flex_wrap_medium=\"\" flex_wrap_small=\"\" flex_wrap=\"wrap\" flex_column_spacing=\"20px\" hundred_percent_height_center_content=\"yes\" equal_height_columns=\"no\" container_tag=\"div\" menu_anchor=\"\" hide_on_mobile=\"small-visibility,medium-visibility,large-visibility\" status=\"published\" publish_date=\"\" class=\"\" id=\"\" margin_top_medium=\"\" margin_bottom_medium=\"\" margin_top_small=\"\" margin_bottom_small=\"\" margin_top=\"\" margin_bottom=\"\" padding_top_medium=\"\" padding_right_medium=\"\" padding_bottom_medium=\"\" padding_left_medium=\"\" padding_top_small=\"\" padding_right_small=\"\" padding_bottom_small=\"\" padding_left_small=\"\" padding_top=\"\" padding_right=\"0px\"..." taxonomy_category: - "Hydro" --- # Gafr Hydro, Nant Peris #### Mechanical refurbishment of a Twin Jet Canyon Turbine on Gafr Hydro Scheme at Ty Isaf Farm, Nant Peris **Project overview** The client reported excessive noise and vibration being produced by the turbine generator in the powerhouse. Upon diagnosis it was found that the vibration was likely caused by miss-alignment, excessive wear on the turbine-generator coupling, generator bearings and the turbine bearings. As a result the hydro scheme was shut down to avoid further damage, but in doing so it no longer produced revenue. The scope of these works included: - Replacing the existing coupling - Replacement of the generator bearings - Replacement of the turbine bearings - Generator reconnection and shaft alignment ## Removing Pelton runner ## Turbine bearing **Impact** The Scheme is a 350kw hydro turbine therefore when running it produces a reasonable amount of renewable energy, offsetting carbon and contributing a sizable, diversified revenue stream for the farmer. **The challenge** Once the site team stripped down the turbine-generator they discovered that there was significant wear on the pillow block housings that hold the bearings. There were Issues with the new coupling that had been provided, meaning that the shaft had to be carefully remeasured and tolerance for interference fit specified. The original temperature sensors didn’t fit in the new bearing housings. ## Canyon Twin Jet Turbine generator **Our solution** The team had to use their engineering experience to redesign, modify and overcome the issues. The key was to react quickly in diagnosing the issues and to take the necessary measurements to get replacement parts ordered straight away. With regards to the temperature sensors the team had to think outside the box and locate a spare grease port, that with some modification was able to accommodate an alternative sensor that still provided the same signal to the PLC. “Despite the difficulties encountered, the project was a success. The hydro scheme is running well, generating electricity and bringing in revenue.” **Murdo Jamieson – Dulas Project Manager** By [Annika Faircloth](https://dulas.org.uk/author/dulasannika/) Published On: February 6, 2026 Share: [https://www.facebook.com/sharer.php?u=https%3A%2F%2Fdulas.org.uk%2Fgafr-hydro-nant-peris%2F&t=Share%3A](https://www.facebook.com/sharer.php?u=https%3A%2F%2Fdulas.org.uk%2Fgafr-hydro-nant-peris%2F&t=Share%3A) [https://x.com/intent/post?text=Share%3A&url=https%3A%2F%2Fdulas.org.uk%2Fgafr-hydro-nant-peris%2F](https://x.com/intent/post?text=Share%3A&url=https%3A%2F%2Fdulas.org.uk%2Fgafr-hydro-nant-peris%2F) [https://www.linkedin.com/shareArticle?mini=true&url=https%3A%2F%2Fdulas.org.uk%2Fgafr-hydro-nant-peris%2F&title=Share%3A&summary=Mechanical%20refurbishment%20of%20a%20Twin%20Jet%20Canyon%20Turbine%20on%20Gafr%20Hydro%20Scheme%20at%20Ty%20Isaf%20Farm%2C%20Nant%20Peris%20Project%20overview%20%0D%0A%0D%0AThe%20client%20reported%20excessive%20noise%20and%20vibration%20being%20produced%20by%20the%20turbine%20generator%20in%20the%20powerhouse.%20Upon%20diagnosis%20it%20was%20found%20that%20the%20vibration%20was%20likely%20caused%20by%20miss-alignment%2C%20excessive%20wear%20on%20the%20turbine-generator%20coupling%2C](https://www.linkedin.com/shareArticle?mini=true&url=https%3A%2F%2Fdulas.org.uk%2Fgafr-hydro-nant-peris%2F&title=Share%3A&summary=Mechanical%20refurbishment%20of%20a%20Twin%20Jet%20Canyon%20Turbine%20on%20Gafr%20Hydro%20Scheme%20at%20Ty%20Isaf%20Farm%2C%20Nant%20Peris%20Project%20overview%20%0D%0A%0D%0AThe%20client%20reported%20excessive%20noise%20and%20vibration%20being%20produced%20by%20the%20turbine%20generator%20in%20the%20powerhouse.%20Upon%20diagnosis%20it%20was%20found%20that%20the%20vibration%20was%20likely%20caused%20by%20miss-alignment%2C%20excessive%20wear%20on%20the%20turbine-generator%20coupling%2C) [https://api.whatsapp.com/send?text=https%3A%2F%2Fdulas.org.uk%2Fgafr-hydro-nant-peris%2F](https://api.whatsapp.com/send?text=https%3A%2F%2Fdulas.org.uk%2Fgafr-hydro-nant-peris%2F) [mailto:?subject=Share%3A&body=https%3A%2F%2Fdulas.org.uk%2Fgafr-hydro-nant-peris%2F](mailto:?subject=Share%3A&body=https%3A%2F%2Fdulas.org.uk%2Fgafr-hydro-nant-peris%2F) Strata Florida water treatment works hydroelectric scheme Strata Florida water treatment works hydroelectric scheme [Read more](https://dulas.org.uk/strata-florida-water-treatment-works-hydroelectric-scheme/) In situ control panel upgrades at hydro scheme In situ control panel upgrades at hydro scheme [Read more](https://dulas.org.uk/in-situ-control-panel-upgrades-at-hydro-scheme/) An 800kW run-of-river hydro scheme near Loch Lomond An 800kW run-of-river hydro scheme near Loch Lomond [Read more](https://dulas.org.uk/an-800kw-run-of-river-hydro-scheme-near-loch-lomond/) Coanda screens in the Himalayas Coanda screens in the Himalayas [Read more](https://dulas.org.uk/coanda-screens-in-the-himalayas/) Fit for the future: Dulas upgrade Dŵr Cymru Welsh Water’s Elan Valley scheme Fit for the future: Dulas upgrade Dŵr Cymru Welsh Water’s Elan Valley scheme [Read more](https://dulas.org.uk/elan-valley-upgrade/) Increasing output through optimisation at the Llyn Brianne hydroelectric plant Increasing output through optimisation at the Llyn Brianne hydroelectric plant [Read more](https://dulas.org.uk/increasing-output-through-optimisation-at-the-llyn-brianne-hydroelectric-plant/) Inverhaggernie intake refurbishment Inverhaggernie intake refurbishment [Read more](https://dulas.org.uk/inverhaggernie-intake-refurbishment/) Glenmore Control Panel Refurbishment Glenmore Control Panel Refurbishment [Read more](https://dulas.org.uk/glenmore-control-panel-refurbishment/) Atholl Estates Run of River Hydro Scheme Atholl Estates Run of River Hydro Scheme [Read more](https://dulas.org.uk/atholl-estates-run-of-river-hydro-scheme/) Balnacarn Hydro Scheme Balnacarn Hydro Scheme [Read more](https://dulas.org.uk/balnacarn-hydro-scheme/) Iwrch Hydro Scheme Refurbishment Iwrch Hydro Scheme Refurbishment [Read more](https://dulas.org.uk/iwrch-hydro-scheme-refurbishment/) Upper Bryn Cowlyd 200kW new build Upper Bryn Cowlyd 200kW new build [Read more](https://dulas.org.uk/upper-bryn-cowlyd-200kw-new-build/)