A return visit to Penllergare Valley Woods hydropower scheme

On our recent trip to the London we decided to bring the car and take the ferry to Fishguard to visit some of the hydropower sites we have worked on over the last year. Our first port of call was a visit to Penllergare Valley Woods, a picturesque landscape hidden away in a steep valley just a stone’s throw, yet a world away, from the M4 in north Swansea.

The Archimedean Screw along side the man made waterfall

The Archimedean Screw along side the man made waterfall

As part of the upgrade and restoration of Penllergare Valley Woods a 30kW Archimedean Screw Hydro Turbine was installed to ensure a sustainable future for Penllergare Valley. A little over a year ago the hydropower scheme was commissioned and is now generating clean green electricity to power the new visitor centre with excess being sold back to the national grid. The Archimedean Screw with a length of 11m and a capacity of 2880 m3/h is situated next to the waterfall. The enclosed compact design was the preferred design of screw for this particular site as the design minimised the installation cost and doesn’t intrude on the existing landscape.

30kW Archimedean Screw

30kW Archimedean Screw

With its lakes and waterfalls, terraces, panoramic views, exotic trees and shrubs, this forgotten Victorian paradise is being slowly restored and brought back to life by the Penllergare Trust. Penllergare Valley Woods was once a famous gentry estate and home to John Dillwyn Llewelyn, the notable 19-century horticulturalist, philanthropist and pioneering photographer. It is Llewelyn’s design, vision and influence behind the picturesque and romantic landscapes of the park.

A return visit to Penllergare Valley Woods Hydropower schemePenllergare Valley Woods is a place where you can enjoy the sound of birds, delight in the profusion of wild flowers, discover evidence of exotic plantings and uncover for yourself the hidden features of a grand design. Wildlife research carried out by Swansea Council has found the estate is very significant for amphibians and acts as a “corridor” for animals to thrive and move about.

One of the many ancient Rhododendrons in full bloom

One of the many ancient Rhododendrons in full bloom

Through hard work, persistence and community spirit by local volunteers and with the financial support of sponsors and the Friends of Penllergare membership scheme, they have been working hard over the last decade or so to maintain and to restore the Penllergare landscape to the romantic style shown in the photographs of John Dillwyn Llewelyn who created it. The rhododendrons, the legacy of the ‘plant hunting’ Dillwyn Llewlyn family in the 19th centurywere a popular sight along every walk way.
Beautiful woodland walk

Beautiful woodland walk

It was obvious throughout our visit that volunteers had been working hard replanting specimen trees and ornamental shrubberies which had been lost from the existing landscape. They have also been thinning and managing areas of dense trees and shrub to reopen historic views.
A return visit to Penllergare Valley Woods hydropower scheme
Visitors can enjoy over 12km of walks including along the Carriage Drive to the now demolished former home of the Dillwyn Llewelyn family, and also down into the gorge where the family created the upper lake with a stunning man made waterfall. Paths and tracks lead on down alongside the afon Llan as it meanders its way to Fforest fach.
A return visit to Penllergare Valley Woods Hydropower scheme
A return visit to Penllergare Valley Woods Hydropower schemeThroughout the last few years the upper lake has been de-silted, and steps, terraces, the stone-arched Llewelyn bridge, waterfalls and cascades have been repaired and restored to reinstate the picturesque and romantic design.
Some of the many ancient trees

Some of the many ancient trees

A return visit to Penllergare Valley Woods hydropower schemeUsing photographic evidence from the 19th century, the old stone bridge was recreated in the traditional style by local stonemasons.

The original stone bridge

The recreated stone bridge

After walking for hours and checking out the Archimedean Screw we spent some time browsing through the information books and leaflets in the visitor centre and then enjoyed a cup of coffee at the small cafe which has stunning views from the cafe terrace to the upper lake. If you’re ever in the area it is well worth a visit. Dogs are also welcome 🙂 🙂

Hydropower installation and restoration of Penllergare Valley Woods

Located on the northern fringe of Swansea, Penllergare Valley Woods was once a famous gentry estate and home to John Dillwyn Llewelyn, the notable 19-century horticulturalist, philanthropist and pioneering photographer. It is Llewelyn’s design, vision and influence behind the picturesque and romantic landscapes of the park.

Hydropower installation and restoration of Penllergare Valley Woods

Photo credit ~ One Historic Garden ~ Penllergare Valley Woods

For almost half a century Penllergare Valley Woods was neglected, vandalised and threatened by development and so the Penllergare Trust was formed in 2000 as an independent charity with the aim of restoring and regenerating the Grade II listed Penllergare Valley Woods to its former stunning glory. The leases of Valley Woods were finally assigned to the Trust on 26th April 2012, effectively securing them for public benefit until 2116 – that’s 104 years! This in turn initiated the award of £2.4m by the Heritage Lottery Fund through it’s Parks for People Programme to support the first phase of an ambitious £2.9m restoration scheme focussed on the upper end of the valley.

Hydropower installation and restoration of Penllergare Valley Woods

Manmade waterfall at Penllergare Valley Woods

It’s a place where you can enjoy the sound of birds, delight in the profusion of wild flowers, discover evidence of exotic plantings and uncover for yourself the hidden features of a grand design. Wildlife research carried out by Swansea Council has found the estate is very significant for amphibians and acts as a “corridor” for animals to thrive and move about.

Hydropower installation and restoration of Penllergare Valley Woods

Photo Credit ~ One Historic Garden ~ Woodland walkway at Penllergare Valley Woods

The restoration of Penllergare Valley Woods will provide an essential green space to relax, explore and have fun in as well as creating jobs and providing training opportunities for local people. The involvement of local volunteers was vital to the success of this project and it’s fantastic to see so many people  involved, learning new skills and playing their part in taking the local  heritage into the future.

Hydropower installation and restoration of Penllergare Valley Woods

The arrival on site of the 30kW closed compact Archimedean Screw – Photo ~ Philip James

As part of the upgrade and restoration of Penllergare Valley Woods a 30kW Archimedean Screw Hydro Turbine was installed to ensure a sustainable future for Penllergare Valley.

Hydropower installation and restoration of Penllergare Valley Woods

Lifting the Archimedean Screw into position

The development of the hydropower scheme in Penllergare Valley Woods will generate sufficient power to meet the needs of the sites new visitor centre and excess sold to the National Grid, raising an expected £10,000 per year for the trust.

Hydropower installation and restoration of Penllergare Valley Woods

Lowering the Archimedean Screw into position

The Archimedean Screw with a length of 11m and a capacity of 2880 m3/h is situated next to the waterfall at Penllergare Valley Woods. The hydropower scheme was designed by Mannpower Consulting Ltd and the Archimedean Screw was manufactured by Dutch company Landustrie.

Hydropower installation and restoration of Penllergare Valley Woods

The Archimedean Screw insitu beside the waterfall

The enclosed compact design was the preferred design of screw for this particular site as the design minimises the installation cost and doesn’t intrude on the existing landscape.

Archimedean Screw with ell pass running along side

Archimedean Screw with eel pass running along side

The Archimedean Screw is placed into the bank side and sits at an angle that roughly matches the existing natural profile of the ground.  Three clear panels along the length of the screw will enable the functioning of the screw to be monitored and the workings demonstrated. It could therefore be used to educate the public about hydro electricity and alternative energy sources. Once in-situ most surrounding areas will be dressed with soil and stone and this will enable it to blend in with the surrounding area.

Decorative stone arches containing drain down pipes for the lake

Decorative stone arches containing drain down pipes for the lake

Decorative stonework on the interior of the arches

Decorative stonework on the interior of the arches

We are heading over to begin the commissioning of the scheme at the beginning of February. Since our arrival on site the newly built Llewelyn Bridge has been opened to the public.

Photo Credit ~ Penllergare Valley Trust ~ The newly built Llewelyn Bridge

Photo Credit ~ Penllergare Valley Trust ~ The newly built Llewelyn Bridge

On the 9th April the Penllergare Valley Woods Archimedean screw hydro generator was commissioned and handed over to the Penllergare Trust. Initially, the electricity generated will feed the coffee shop, woodland centre and the office cabin by the car park, thus reducing significantly the running costs. The Trust are negotiating with Ofgem and their electricity provider to buy surplus electricity from them by feeding it in to the National Grid. All of the income derived from this will be ploughed back into running and maintaining Penllergare Valley Woods for everyone to enjoy.

The site of the Archimedean Screw installation and lake

The site of the Archimedean Screw installation and lake

The commissioning of the Archimedean Screw was based on the partially de-silted lake configuration. It will need to be adjusted once the lake works have been completed later in the Summer. In the meantime the Trust plan to move soil, place stones and later, plant trees and shrubs around the works to better integrate it all into the landscape. Once this work has been completed, the area around the turbine will be open for people to take a look and to see the screw turning through the specially designed viewing panels in the top of the screw housing.

Generating clean green electricity

Generating clean green electricity

If you are the owner of a potential hydro site or are a community group interested in developing a hydro project for community use please contact us. We design, install and commission hydropower schemes in Ireland and the UK.