Coire glas hydro scheme

  • Category: Renewables
  • Energy type: Hydro
  • Project type: Project

Coire Glas is the first new large scale pumped storage scheme to be developed in UK for over 30 years.

Coire Glas is a proposed 1500MW pumped storage scheme located to the south west of Laggan Locks near Loch Lochy. 

Why do we need pumped storage?

In a time where demand for energy is growing, much work is being carried out to meet the challenges energy consumption presents. Over the last 15 years as the UK works to meet decarbonisation targets the make-up of the UK energy network has changed. We have shifted from a grid driven by fossil fuels to a more mixed network. While research into batteries carries on pumped storage is a proven technology that is well placed to help provide a secure supply of energy across the UK, and especially in an energy system with high levels of renewable generation.

Its extremely short response times means that pumped storage can help provide short term balancing services to the grid such as in the event of an unexpected plant failure, as cover for variable renewable generation, or to respond to sudden increases in demand. They can start generating electricity in less than 15 seconds when in a spinning cycle and within just 2 minutes from rest.

Pumped storage is also the most efficient of currently available storage technology, at up to 80%, and is able to store and flexibly provide reliable capacity over an extended period of time. Pumped storage can provide load balancing, facilitating the integration of variable renewable generation, as well as contributing to security of supply, through supporting a diversified energy system.

 

Coire Glas - The story so far

In December 2013 SSE was granted planning approval for a 600MW pumped storage hydro scheme at Coire Glas, this consent remains valid until 2021. Despite the obvious benefits that pumped storage offers, progressing the Coire Glas scheme requires overcoming a number of commercial and regulatory challenges. These include changes in the existing transmission charging regime for pumped storage and a satisfactory and supportive long-term public policy and regulatory framework.

Since obtaining consent, SSE has been working with key stakeholders including the Scottish Government, Department for Business, Energy and Industrial Strategy (BEIS), OFGEM and other bodies with the aim of achieving the necessary electricity market recognition of the benefits that pumped storage hydro will bring to the electricity market and its wider socio-economic benefits.In a time where demand for energy is growing, much work is being carried out to meet the challenges energy consumption presents. Over the last 15 years as the UK works to meet decarbonisation targets the make-up of the UK energy network has changed. We have shifted from a grid driven by fossil fuels to a more mixed network. While research into batteries carries on pumped storage is a proven technology that is well placed to help provide a secure supply of energy across the UK, and especially in an energy system with high levels of renewable generation. 

COIRE GLAS - 1500 MW

SSE submitted a scoping request for a revised 1500MW on 12th May 2017. The revisions to the consented scheme now being proposed are intended to maximise the potential of the site and provide options for better aligning the project with the current and future market framework, thereby aiding delivery of the project.

We are proposing to increase the generating capacity of the project from the consented 600 megawatts (MW) up to 1500 MW. This increase in capacity will, however, bring little change to the current external elements of the scheme with the majority of the changes being in the underground space required to house the larger turbines and pass the increased flow rates of water and as such will not be visible. External elements of the project, such as the dam, upper reservoir, construction access, jetty and administration building, will be similar in size and nature to that of the already consented development.

Key Points:

  • The majority of changes to the scheme will be in the underground space required to house the larger turbines and pass the increased flow rates of water, and as such will not be visible;
  • There is no proposal to increase the size of the previously consented upper reservoir;
  • The amount of rock excavated from the underground works will increase compared to that previously consented;
  • Inclusion of a surface intake tower and a surge shaft to respond to fluctuation in pressure;
  • There will be an increase in the footprint of the lower tailrace and outlet structures;
  • The flow rate of water being transferred between the upper and lower reservoirs would be greater, however, it is not intended to manage Loch Lochy out with the existing level range (as per the already consented development); and
  • All access routes in and out of the site would remain the same as previously consented

Following the submission of the scoping report for the revised project on Friday 12 May, the Scottish Government sought guidance from statutory bodies (Highland Council, SEPA and SNH) who defined the scope for the Environmental Impact Assessment (EIA) required for the proposed larger scheme.

Since summer 2017, SSE has undertaken a number of environmental surveys and impact assessments by professionally qualified specialists to assess the potential effects of the proposed scheme. The results of these assessments will be reported within an EIA Report. The key aspect of the assessment activities is to assess and present the ‘worst case scenario’ for consideration in determination of the application.

Consideration of technical feasibility and environmental constraints identified through rigorous and extensive survey effort, in combination with consultation with various statutory and non-statutory environmental agencies and local communities, has led to the finalised scheme that will be presented in the Section 36 submission to be made to Scottish Ministers in March 2018. At this point the proposed development will be open to public consultation and comment from a wide range of consultees with the final decision to be made by Scottish Ministers.

 

If you do have any questions about the proposed scheme , please do not hesitate to email: corinna.scholes@sse.com

Quick overview

Pumped storage schemes involve two bodies of water at different heights. During periods of low demand for power, electricity is used to pump water from the lower loch to the upper reservoir. The water is released to create energy at a time when demand is high. A key advantage of developing a pumped storage scheme at Coire Glas is the site's proximity to a large lower reservoir (Loch Lochy). There is significant elevation of around 500m between the upper and lower reservoir sites over a relatively short distance.

Latest news

In May 2017 a scoping request was submitted to The Scottish Government for a revised 1500MW Coire Glas pumped storage scheme. On 28th May 2017 we held a public exhibition to give members of the community and interested parties an opportunity to meet the project team and discuss the project.

Exhibition materials can be view here.

Community

We recognise that our investments in new electricity generation benefit from the co-operation of the local community in a variety of ways, particularly during the construction phase. In recognition of this, our policy is to establish long-term funds to support community projects in areas where we are developing generation projects. 

Please visit our Communities page for more information.

More information

Coire Glas 1500MW Project Information

Important documents

Coire Glas 600 MW Project Information

Coire Glas 600*300

The proposed scheme involves constructing a dam and the creation of a new reservoir formed at Loch a' Choire Ghlais. Water will be transferred between the new reservoir and an underground cavern power station via a headrace tunnel; and between the power station and Loch Lochy via a tailrace tunnel.

It could offer significant benefits to the GB electricity system in terms of capacity, balancing services and flexibility, particularly as the energy system moves towards an increasing amount of variable generation capacity.

Coire Glas 3 - 600*300

The Scottish Ministers granted Coire Glas consent in December 2013 meaning it could be the first new large scale pumped storage scheme to be developed in Great Britain for over 30 years.

The combination of the size, flexibility and short response time means that Coire Glas, and pumped storage schemes generally, can provide a range of benefits across the whole GB electricity system in a way that no other proven technology can. However, despite the obvious benefits that pumped storage offers, making a Final Investment Decision to progress the Coire Glas scheme will require overcoming a number of commercial and regulatory challenges. These include changes in the existing transmission charging regime for pumped storage and a satisfactory and supportive long-term public policy and regulatory framework.


All of this means that a decision on whether to progress with Coire Glas will not be taken until late 2017 at the earliest.