Wind Repowering
Breathe New Life Into Your
Existing Wind Turbine
Extend your turbine's working life by 25+ years at just 30–50% of the cost of full replacement. We replace ageing inverters and controllers, upgrade grid compliance and integrate your turbine with solar and battery storage.
Why repower?
A smarter alternative to replacement
Most wind turbines installed in the 2000s and early 2010s are now reaching the end of their original inverter and controller lifespan — typically 10 to 20 years. Rather than decommissioning a structurally sound turbine, repowering replaces the electrical heart of the machine at a fraction of the cost of a new installation.
Our repowering service covers full inverter and controller replacement, G99 and G100 grid compliance upgrades to satisfy your DNO, and seamless integration with existing or new solar PV arrays and battery storage systems. The result is a turbine that performs like new, meets current regulations and can form the wind element of a complete farm micro grid.
Every project begins with a thorough condition survey covering the tower structure, blade condition, gearbox, yaw system and all electrical components. We provide a detailed feasibility report before any work begins, so you know exactly what is involved and what to expect.
Request a condition survey10–20 yrs
Typical turbine age at repowering
30–50%
Cost saving vs full replacement
25+ yrs
Extended turbine lifespan
100%
Self-use potential with solar & storage
What we do
Our repowering services
Inverter & controller replacement
We replace ageing inverters and turbine controllers with modern, efficient units — restoring full output and grid compliance without touching the tower or blades.
Grid compliance upgrades
Full G99 and G100 compliance upgrades ensure your turbine meets current DNO requirements and can continue exporting to the grid legally and safely.
Integration with solar & storage
Repowered turbines can be integrated with solar PV arrays and battery storage to create a complete farm micro grid — maximising self-consumption year-round.
Condition survey & feasibility
Every repowering project begins with a thorough condition survey of the tower, blades, gearbox and electrical systems to confirm feasibility and identify any additional works.
Our process
How wind turbine repowering works
Repowering is a structured, four-stage process. We carry out every stage in-house, from the initial condition survey through to commissioning and grid reconnection — so you have a single point of contact throughout.
01
Condition survey
We inspect the tower structure, blades, gearbox, yaw system and all electrical components. A detailed written report confirms feasibility and identifies any additional structural or mechanical works required before repowering can proceed.
02
Specification & quotation
Based on the survey findings, we specify the replacement inverter and controller, identify any G99/G100 compliance upgrades required by your DNO, and provide a fixed-price quotation with a clear project timeline.
03
Installation
Our engineers carry out the full electrical replacement, including inverter, controller, protection relays and any associated wiring. All work is carried out to IET Wiring Regulations and manufacturer specifications, with minimal turbine downtime.
04
Commissioning & grid reconnection
We commission the repowered turbine, carry out all G99/G100 testing and documentation, and liaise with your DNO to restore grid export. You receive a full commissioning certificate and updated electrical installation certificate.
Why Squirrel Energy
Specialist wind repowering expertise in the North of England
Squirrel Energy has been working with farm and rural wind turbines across Lancashire, Yorkshire, Cumbria and the North West for many years. We understand the specific makes and models common in the UK agricultural sector — Britwind, EWT, Endurance, Gaia, Proven and Evance — and we hold the technical knowledge to source compatible replacement components for each. We also supply and install new GEVI wind turbines for farms and commercial sites that want to add wind generation to complement their solar arrays.
Unlike general electrical contractors, we approach every repowering project as renewable energy specialists. That means we consider not just the immediate inverter replacement, but the long-term performance of your turbine as part of a wider farm energy strategy. Where appropriate, we will recommend integrating your repowered turbine with solar PV and battery storage to create a complete micro grid that maximises self-consumption and Smart Export Guarantee revenue.
We are NAPIT approved and carry full public liability and professional indemnity insurance. All electrical work is notified to the relevant authority and certificated to current IET Wiring Regulations. Our condition survey reports are written to a standard that satisfies lenders, insurers and planning authorities — useful if you are refinancing or selling a property with a wind turbine.
The economics
The financial case for repowering
A wind turbine that has stopped generating is a stranded asset. Decommissioning costs money, and a replacement turbine requires a new planning application, new grid connection agreement and full installation cost — typically £80,000 to £300,000 depending on size. Repowering avoids all of that. By replacing only the electrical components that have failed or are approaching end of life, you restore full generation at 30 to 50 percent of replacement cost.
A repowered turbine can generate for a further 25 years or more, depending on the structural condition of the tower and blades. For a 50kW turbine generating 100,000kWh per year, that represents £15,000 to £25,000 of annual value in self-consumption savings and Smart Export Guarantee payments — a payback on repowering costs of typically two to four years.
If your turbine is currently idle due to an inverter or controller failure, every day it is not generating is lost revenue. Contact us for a free initial assessment — we can usually advise on viability within 48 hours of receiving your turbine make, model and fault description.
Common questions
Wind turbine repowering — your questions answered
What does wind turbine repowering actually involve?
Repowering replaces the electrical components that wear out first — the inverter, controller and associated power electronics — while keeping the tower, blades, gearbox and nacelle in place. We carry out a full condition survey first, then replace only what is needed. The result is a turbine that performs like new and meets current G99/G100 grid connection standards.
How much does repowering cost compared to a new turbine?
Repowering typically costs 30–50% of the price of a full replacement turbine. For a 50kW machine, that can mean saving £80,000–£150,000 compared to decommissioning and installing new. The exact saving depends on the turbine model, its condition and the scope of electrical work required.
Which turbine makes and models can you repower?
We work with a wide range of small and medium wind turbines common in the UK agricultural sector, including Britwind, EWT, Endurance, Gaia, Proven and Evance machines. If your turbine is not listed, contact us — we assess each project individually and can source compatible inverter and controller solutions for most makes. We also supply and install new GEVI wind turbines for farms and commercial sites looking to add wind generation alongside solar — visit our farm micro grid page for details.
Will my turbine meet current DNO grid connection requirements after repowering?
Yes. Part of every repowering project is a G99 or G100 grid compliance upgrade to satisfy your Distribution Network Operator. We handle all the technical documentation and liaise with your DNO on your behalf, so you do not need to navigate the process yourself.
Can a repowered turbine be integrated with solar panels and battery storage?
Absolutely — this is one of the key advantages of repowering. Modern inverter and controller technology allows your wind turbine to be integrated into a complete farm micro grid alongside solar PV arrays and battery storage systems. This means you can store wind generation overnight and use it during the day, or export intelligently under the Smart Export Guarantee.
How long does a repowering project take from survey to completion?
A typical repowering project takes four to eight weeks from initial condition survey to commissioning, depending on parts availability and the scope of work. We provide a detailed project timeline in our feasibility report before any work begins, so you know exactly what to expect and when your turbine will be back generating.
What are the technical specifications of the GEVI wind turbines you install?
GEVI turbines are vertical-axis small commercial machines rated at 3 kW nominal power. Key specifications: rotor diameter 6 m, rotor height 4 m, blade height 2.9 m, cut-in wind speed 2.4 m/s, nominal wind speed 10.5 m/s, cut-off wind speed 17 m/s, noise level below 38 dB SPL at 10 metres, and a 25-year operating life. The low cut-in speed of 2.4 m/s means the turbine begins generating in light winds — well suited to average wind conditions across Lancashire, Yorkshire and Cumbria. Annual energy output varies by site; we carry out a site-specific wind resource assessment as part of every installation proposal.
Free assessment
Ready to repower your turbine?
Get in touch for a free assessment. We'll review your turbine's age, condition and grid connection and provide a clear proposal for repowering.