Parc Adfer - Turning trash into energy

Parc Adfer is the name given to a £800m waste to energy facility located on the Deeside Industrial Park in Flintshire, North Wales. The plant which became fully operational in December 2019 can process up to 200,000 tonnes of non-recyclable waste per year and generate up to 17MW of electricity which is fed to the national grid, enough electricity to power up to 30,000 homes.

The facility was built through a public-private partnership (PPP), with Wheelabrator Technologies chosen to deliver and manage the project, Wheelabrator which operates other waste-to-energy facilities in the UK and US will operate the plant for 25 years. The company processes over 8 million tonnes of waste per year across its 25 sites, generating 732 MW of electricity, enough to power 671,000 homes.

 

The building itself seems relatively modest for a plant capable of proccessing 200,000 tonnes of waste a year

Five Welsh authorities worked in collaboration with assistance from the Welsh Government to develop the proposal, which is known as the North Wales Residual Waste Treatment Project (NWRWTP). The 5 local authorities are Flintshire, Isle of Anglesey, Gwynedd, Conwy, and Denbighshire. It is from these 5 local areas where the majority of waste is collected.

Local waste from Flintshire is generally brought in directly by refuse vehicles, whilst waste from further afield is brought in by articulated vehicles with high volume capacity trailers. Waste transfer sites receive waste from refuse vehicles, which is then transferred to the trailers which can each carry up to 27 tonnes. In this way, local authorities can reduce the number of vehicles that are needed to deliver waste to the facility.  

The construction of the plant generated some local opposition, with people raising concerns about air pollution, however, Wheelabrator say “Our facilities use the most advanced environmental control systems to meet and exceed some of the most stringent environmental standards in the world” adding “Waste-to-energy facilities are required to comply with strict air quality limits established by the European Waste Incineration Directive”. [1]  

Indeed, modern waster-to-energy facilities are nothing like the incinerators of old. High burning temperatures up to 1110°C and filtration systems can burn off and then filter out much of the particulate matter. The facilities themselves can reduce the volume of the original waste material by 95-96%. Whilst Metals which remain within the waste can be removed and sent on to be recycled, the remaining ash can also be recycled and is used within the construction industry as secondary aggregate. 

Further to this, Wheelebrator refer to a study that was undertaken on behalf of the German Federal Environmental Agency [2]. The report demonstrates that waste-to-energy facilities can have a positive net impact on greenhouse gas emissions through the reduction of methane emissions, which would normally be generated by waste which has been sent to landfill. Whilst methane only accounts for 10% of greenhouse gases globally it can trap 84 times more heat per mass unit than carbon dioxide

View from Weighbridge Rd

Of course, there remain pros and cons, as such facilities do still emit Co2 into the atmosphere and very small amounts of other particulates, even if the amounts are so small, as not to pose a risk to the environment or people living close by. In general though, energy recovery from waste can play a crucial role in managing the waste that we the public produce. 

Flintshire Country Council recycles 58,000 tonnes of waste per year, but this still only accounts for about 69% of the total amount of waste that is recycled. This is significantly above the national average for Wales, which stands at 60% of waste recycled. However, this still leaves a huge volume of waste that either can't be recycled or isn't yet being recycled by the public 

So, whilst as much as 40% of the waste generated by households in Wales and across the UK remains un-recycled or un-recyclable, we must find solutions to disposing of the waste which we produce, a solution which doesn't involve burying it in the ground for future generations to deal with.

 

[1] https://www.wtiparcadfer.co.uk/environment-and-benefits/environmental-performance/

[2] https://www.wtienergy.com/sites/default/files/German%20BDE_klima_abfall_en.pdf

 

 

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A494 Dee bridge renewal

The A494 at the point where is crosses the River Dee carries over 60,000 vehicles per day and is a vital link which connects North West England with North Wales. It also forms part of the TEN-T European transport network, linking ports to the East of England with the port of Holyhead. The road also provides employees who live in North Wales access to the Deeside Industrial Park, which is to the east of the River Dee.

The video below gives an overview of the A494 from the junction with the A540, located to the west of the M56 (where the M56 becomes the A494), across the Dee bridge to Queensferry.

The bridge over the River Dee was constructed in the 1960s and carries almost double the number of vehicles that it was designed for, this has lead, according to the Welsh Government to “deterioration to some structural features”[1]. Therefore in 2018 it was announced that the bridge was to be renewed, with a public consultation held during summer 2018 which outlined the proposals.

A494 Dee bridge

As an important link carrying 60k vehicles per day it is vital that the A494 remains open, closing the section of road simply isn't option. So the Welsh Government working with the North and Mid Wales Trunk Road Agency appointed Mott MacDonald and their partners Richards, Morehead & Laing to consider options for the replacement of the bridge.

The final proposal which was put to the public for consultation will see the construction of an all new 4 lane bridge crossing the River Dee to the south of the existing A494 bridge. Once the new bridge is complete, engineers will begin to remove and then replace the deck of the existing bridge. Once complete the 2 bridges will provide 3 lanes, plus a hard shoulder in each direction. The additional lane will provide entry and exit from the A548 and Queensferry junctions, this will give drivers more time to merge onto or leave the A494 and help to remove a current pinch point.

A494 Dee bridge proposal [click to enlarge]

The alignment of the A494 on east side of the river had already been altered in 2004 as part of the A494 “Drome Corner” upgrade undertaken by Highways England. The alignment change was to allow for an increased number of lanes which would have crossed the River Dee and continued up Aston Hill to the junction with the A55. However after strong opposition from local residents the plans to widen the A494 were cancelled by the Welsh Government in 2007.

The proposals for the new bridge will make use of the altered alignment with the bridge built to the south of the existing bridge. A new section of road will also be constructed west from the new bridge, underneath the Chester to North Wales railway, ending at the junction for Queensferry. Once complete the new bridge and re-decked existing bridge will provide additional benefits for motorists, by providing the 3rd lane and by providing a hard shoulder for motorist should they get into difficulty whilst travelling on that section of the A494.

Building a new bridge was, in reality the only viable option. The construction of the existing bridge is such that it is not possible to work on either side of the carriageway at a time, whilst trying to keep at least 1 lane of traffic open in each direction. Also the idea of keeping only 1 live lane open in each direction would have been unthinkable, given the volume of traffic that currently use the crossing.

Dee bridge from underneath

Building a new 4 lane bridge allows for 2 lanes of traffic in each direction to continue to cross the River Dee while work is carried out on the existing bridge. It also makes sense to retain and re-deck the exiting bridge, which apart from the deck is still structurally sound. Putting both sets of work into a single package will allow, not only for the renewal of the bridge but an upgrade of the crossing, which should in itself help to improve the business case for the proposal as a whole.

Work is expected to begin during summer/autumn 2020, subject to Minister's approval. I wasn't able to find out if a completion date has been set, however I would estimate a project of this scale would take at least 18 months, possibly up to 30 months to complete.

It is unfortunate that the urgency of the work means that it will have to take place before work commences on the so called “Red Route”, which will see much of the traffic that currently uses the A494 Dee crossing using a new route. The Red route will make use of the exiting A548, the Flintshire Bridge which was constructed 1998 and a new section of road linking the A548 at Connah's Quay to the A55 close to Pentre Halkyn. Work on this £250m proposal is not due to commence until 2025, subject to approval from Welsh Government.



[1] https://gov.wales/sites/default/files/consultations/2018-11/consultation-document.pdf

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A494 to A55 improvement proposals (part 2)

A494 - A55 Red option

In the first part I described some of the background into the previous attempt to upgrade the A494/A55 corridor, in this second part I will explain in more detail the "Red option" which is currently preferred by the Welsh Government.

The Red option involves construction of roughly 3.5km of new dual carriageway between the A548 and the A55. The proposal also involves grade separating a number of roundabouts along the A548 which provide access to the Deeside Industrial Park.

A494 looking south toward the A550 interchange and Deeside Industrial Park

Although the Red option primarily involves the construction of a new road, there will be some major works involving interfaces with existing roads. A new junction will have to be constructed on top of the junction where the A550 meets the A494, a junction that itself was only completed in 2009. 

Proposed A550/A494/A548 interchange (Click to enlarge)

Image for demonstrative purposes only, not to scale. Alignment is subject to change. 

It appears as if the new junction will be construction so that the A494-A548 route will be the main route to the A55. I assume that signage and lanes will have to be marked in such a way to direct people travelling from England wishing to access the A55 for Wrexham/Chester/Mold via the A494 and those wishing to access the A55 for the North Wales Coast/Anglesey/Holyhead via the new A548 link.

The A548 at the point where it passes the Deeside Industrial Park will be mostly re aligned with the existing carriageway alignment used for exit/entry slips between the new carriageway and roundabouts.

The dumbbell junction on the A584 for Connah's Quay will also have to be relocated as the carriageway will be re aligned to head North West towards the A55. The section of dual A584 currently ends 500 metres after the junction for Connah's Quay. After that the A548 becomes a single carriageway. The current A548 route does eventually meet the A55 but not until it reaches Pensarn some 38km away.

It will be interesting to note if or how the new A584 - A55 link is numbered if it is constructed.

The Welsh government have identified journey time benefits as one of the main benefits of the Red option over that of the Blue option. However there are other potential benefits, such as supporting the case for a new railway station that is proposed within the Deeside Industrial Park on the Wrexham Bidston railway line.

Proposed Deeside Parkway station, image courtesy of the Wrexham-Bidston Rail Users' Association

It is envisaged that the new station as well as providing access to the industrial park for workers, could also provide park and ride facilities for those travelling from Wales wishing to travel to Liverpool. Rather than driving to Liverpool of Hooton station (on the Merseyrail Wirral line), people could park at and travel from Deeside Parkway.

The other obvious benefit over the Blue option is the fact that a lot of the construction will be off the main carriageway. The Blue option involves working on the live carriageway at a point where congestion is already at its worst.

The Red option also provides a diversionary route if problems arise, concurrently the existing A494 would provide access to North Wales if there were problems on the A548. Currently in reality there is only one main route into North Wales and that is the A494-A55 corridor.

Another element to take into consideration is the replacement of the  A494 Dee bridge "which is in a poor structural condition"[1], there are already separate plans being put into place to replace the existing steel and concrete bridge. Replacing the bridge during or after potentially upgrading the A494 would bring with it further disruption. The Red option would at least provide a diversionary route whilst a new bridge is being built.

A decision is expected this year on whether to go ahead and if so which route to progress, so we won't have long to wait. In the meantime you can see how each of the options would look thanks to videos produced by the Welsh Government.

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