As Scotland works towards net zero by 2045, including an ambition of 20GW of onshore wind by 2030, repowering ageing renewable energy developments is becoming a key factor in delivering these objectives. A significant portion of existing onshore wind farms will be approaching the end of their subsidy support period (e.g. those wind farms developed under the Renewables Obligation scheme, which closed to onshore wind projects in 2016), prompting decisions on whether sites should be repowered, have their life extended or be decommissioned.
Attention is shifting towards how existing renewable energy sites can be used more efficiently through repowering, life-extension and the integration of additional technologies. Enhancing the use of existing assets will be critical for maintaining momentum in renewable generation while making efficient use of finite resources.
Developers, landowners, investors and community groups are increasingly asking how existing renewable generation sites can be more productive, better integrated with surrounding land use, and capable of operating for longer, while continuing to deliver economic and community benefits.
A Changing Landscape
Since Scotland’s early renewable developments were constructed, technology and policy have advanced significantly, with modern turbines delivering substantially higher outputs and increasing opportunities for co-location, such as battery storage to enhance system flexibility.
The commercial framework has also evolved. Regular Contracts for Difference (CfD) auction rounds now underpin the economics for new renewables projects, while major network upgrades, such as the Accelerated Strategic Transmission Investment (ASTI), aim to expand and reinforce the electricity transmission system. Planning policy has also progressed, most notably through the introduction of National Planning Framework 4 (NPF4) in Scotland, alongside wider policy reforms.
Against this backdrop, repowering and extension have moved firmly into focus as practical tools to retain and grow renewable capacity while navigating planning, grid and investment constraints.
Routes to Repowering
For existing renewable energy sites approaching mid to end of life, a clear development strategy is essential. While site-specific considerations vary, there are four potential routes for extending the contribution of existing developments:
- Life Extension – the existing development continues to operate for a longer period than originally envisaged.
- Repowering – removing and replacing old infrastructure with newer, more efficient equipment within the same development footprint.
- Physical Extension – building out additional capacity while utilising existing infrastructure, either independently or alongside repowering.
- Hybrid – repowering and/or physical extension combined with co-location of additional technologies, such as battery storage or solar PV.
Each route offers the potential to retain and increase the current renewable energy generating capacity, but all must be progressed in line with current planning, legal, regulatory and environmental frameworks.
Key considerations in practice
Once a development strategy and business case are identified, several practical and legal factors need to be considered.
Land Rights – Land agreements are often a first area of focus. The rights to operate an existing development will typically be held under a time-limited, and often now outdated, lease. At a minimum, land agreements will need to be varied or renegotiated to extend their duration and, often to amend the extent of the land covered by the lease and the permitted use.
Questions may also arise regarding who is best placed to develop the ‘new’ project – this might be the incumbent developer, a new developer or a community body.
In practice, an Option and/or Exclusivity Agreement is often sought while key approvals are progressed (such as consents, grid or CfD). Crucially, these arrangements must allow the existing site to continue operating until there is sufficient certainty that the proposal will proceed.
Grid Connection – Grid connection is another critical consideration. While existing sites benefit from established connections, there is no guarantee that an existing connection can be relied upon for a new or expanded development. A new grid connection may be required, particularly where there is a material increase in generating capacity or change in technology. In some cases, smart design solutions, such as on-site use of power or incorporation of storage, can mitigate grid constraints.
The recent National Energy System Operator (“NESO”) “Gate 2” process, part of the wider grid connection reforms, seeks to prioritise projects that are genuinely ready and deliverable. Greater emphasis is placed on project readiness, land rights and planning before a grid connection is confirmed. As a result, securing grid capacity increasingly requires early engagement and cooperation between developers, landowners and those holding interests in the land.
Planning – Repowering and extension projects will, in most cases, require fresh planning permission or consent. Proposals are assessed under the current policy framework, including consideration of environmental impact, landscape and community engagement. There can be added complexity where new development is proposed on an existing site, such as establishing the appropriate baseline for environmental or landscape and visual impact.
What Can Repowering Deliver?
The potential benefits of extension and repowering are considerable. Increased efficiency through the adoption of modern and complementary technology, retained or expanded generating capacity, longer operational life and utilisation of existing infrastructure, all contribute towards Scotland’s net zero objectives.
Beyond generation, there are wider benefits, including more efficient use of land and natural resources, sustained investment in the economy and supply chain, and continued income streams for private landowners, public landowners and communities, particularly in rural and remote areas.
However, these opportunities are not without challenges. Planning and consenting processes can be lengthy, grid capacity remains constrained, regulatory requirements continue to evolve, and historic subsidy regimes are running out. Without careful planning and coordination, there is a real risk that renewable generation could fall off the network leading to a reduction, or lower net increase, as older assets are retired faster than new or repowered projects are delivered.
Early and regular review of the performance and remaining lifespan of existing operational sites together with pro-active steps to secure land rights, consents and collaboration with appropriate parties, will be key to ensuring opportunities are not missed.
Scotland’s net zero challenge is no longer just about building more renewable energy – it is about making better use of what is already in place. The ability to repower, extend and supplement existing renewable developments at pace may prove just as important as new developments in determining whether net zero target by Scotland’s 2045 is achieved on time.
*Originally featured in The Herald on 30 April 2026: View Article
