Butlers Wood, Essex

500MW Battery Energy Storage System

Zenobē has submitted a planning application for the proposed Butlers Wood Battery Energy Storage System (BESS) near Bulmer Tye, bringing new energy infrastructure investment to Essex.

Part of our portfolio of battery energy storage systems across the UK

Zenobē designs, finances, builds, owns and operates battery energy storage systems (BESS). We help grid operators overcome the challenges in balancing supply and demand and overcoming power stability and constraints as we transition away from fossil fuels towards net zero.

 

By 2027, Zenobē is on track to deliver 1.2GW of battery power, which will make us one of the largest owners and operators of battery storage in the UK.

 

500MW

battery to reduce wasted

wind energy

2026

planning application
submitted

2029

earliest commencement
of construction

Project description

The proposals for the Butlers Wood Battery Energy Storage System (BESS) have evolved through technical assessment, stakeholder engagement and design development. The information presented here reflects the current iteration of the project and will continue to be refined through ongoing engagement and technical work.

 

The site covers approximately 30 acres (~12.2 hectares) of agricultural land located to the south of Bulmer Tye, within the Braintree District Council area in Essex. The land is situated at Ordnance Survey grid reference TL 843 379.

Site location

Butlers Wood location within the surrounding area
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Site layout

Butler's Wood Site Layout
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The site red line boundary spans across two fields. The development and infrastructure will be situated within the main field which is adjacent to Hedingham Road and extends to approximately 22 acres. The field to the southeast, which is adjacent to Butler’s Wood, is being considered for biodiversity and environmental enhancement measures.

 

The development comprises the construction and operation of a battery storage scheme, with a total capacity of up to 500MW. The principal components of the development include:

 

  • 288 battery energy storage units, housing the battery blocks, inverters, heating, ventilation and transformers
  • High voltage supergrid transformers, associated switch gear, harmonic filters and enclosure walls
  • Medium voltage switch rooms, spares containers and a control room each approximately the size of a shipping container
  • Columns for the infrared security lights and CCTV system
  • Low voltage switch rooms and auxiliary transformers

  • Internal access tracks approximately 5m in width

  • Underground cables to connect to the new Butlers Wood substation (currently under construction)

  • A perimeter metal palisade fence

  • Landscape planting and biodiversity enhancement measures

Project programme

The programme below outlines the key stages of the project, from planning and construction through to the site becoming fully operational.

Planning

Zenobē has submitted a full planning application to Braintree District Council for the proposed Butlers Wood Battery Energy Storage System under reference 26/01942/FUL. Planning documents and details of the Council’s consultation process will be available via the Council’s planning portal.

Preparing for Final Investment Decision (FID)

If approved, the project goes through detailed design, procurement of equipment, contract negotiations with suppliers and contractors, discharging pre-commencement planning conditions and undertaking technical financial and legal due diligence to allow our funders to formally sanction the go-ahead of the project. This usually takes about one year to complete.

Construction

Construction work begins with the clearance of site and the earthworks to create a level platform on which the development can be built. Once the earthworks are completed, the foundations and cable ducts will be installed and when complete, the batteries and other electrical equipment will be delivered to site, installed and connected. The construction phase for a site of this scale is about 18 months.

Commissioning

The battery and all supporting electrical equipment are thoroughly tested for several months before being connected to the National Grid.

Operation

Once connected to the electricity network, the battery site will begin delivering essential services to support more efficient and reliable grid operation. Operational maintenance requirements are minimal, meaning there will be very few vehicle movements to and from the site after construction is complete.

Decommissioning

After 40 years, all equipment and structures will be removed from site. Most equipment and materials can be reused or recycled and the land will be reinstated back to agricultural use.

Community benefit

If approved, the project will create a Community Benefit Fund to support local projects and initiatives that deliver lasting value for the communities surrounding the site.

 

Through our consultation programme, residents highlighted a range of priorities for future investment, including:

  • Community facilities and village halls
  • Environmental and biodiversity projects
  • Play and recreation spaces
  • Schools and educational initiatives
  • Footpaths, cycle routes and local infrastructure

 

Further details on the Community Benefit Fund will be shared as the project progresses.

Stay informed

We would like to thank everyone who attended our consultation events, completed our survey, got in touch with the project team or shared feedback during the development of the proposals. Community feedback helped inform the evolution of the project, including refinements to the site layout, access arrangements and landscaping proposals.

 

The planning application has now been submitted to Braintree District Councilunder reference 26/01942/FUL. Information on how to view application documents and participate in the consultation process can be found through the Council’s planning portal.

 

We remain committed to open and transparent communication throughout the planning process. If you have any questions about the project or would like to stay informed about future updates, please contact the project team or join our mailing list below.

Who are Zenobē?

Zenobē designs, builds and operates battery energy storage systems (BESS) that maximise the uptake of renewable power, ensuring it does not go to waste and can power our homes and our transport.

Founded in the UK in 2017, we will deliver 1.2GW worth of battery storage projects by 2027.

 

Photo of a Zenobe battery on site

Commitment to net-zero

The UK Government has made a legal commitment to cut carbon emissions to net-zero. With the move away from fossil fuels, the demand for electricity will increase with the need to electrify transport, heating and more.

 

Battery storage plays a key role in helping the UK meet its net zero ambitions as it allows a greater amount of cheap renewable energy to be deployed whilst providing critical balancing and stability services without the need for traditional fossil power stations.

What is a grid-scale battery and what does it do?

Renewable energy is intermittent which means at any time there is a risk of it generating too much or too little in relation to demand from homes, businesses and transport.

 

Batteries provide ‘flexibility’ and the ability to balance the fluctuating supply and demand on the electricity system which comes with increased deployment of renewable and decentralised energy generation. For example, if wind turbines are generating more power than demand allows, batteries store this surplus energy. When wind generation is low but demand is high, battery operators release the stored electricity back into the system, ensuring this energy is not wasted.

 

Batteries also provide a wide range of additional services needed to maintain grid stability and keep the lights on. Our batteries have been the first in the world to provide fast reserve, to be used for reactive power and to manage grid constraints on the transmission network.

 

Our bespoke solutions range from ancillary, balancing and wholesale trading, to providing inertia, short circuit level, and voltage management.
Zenobē also provides non-wire alternative solutions that reduce or eliminate expensive network reinforcement costs. These are specific solutions that are essential to a decarbonised electricity system.

Rows of battery storage units at Zenobē’s Capenhurst 100 MW site, with a transmission pylon in the background.

Why Butlers Wood?

The Butlers Wood substation – currently under construction – sits on the 400kV electricity transmission network between Bramford and Pelham. This is the only 400kv circuit transmitting electricity west from Bramford, and it faces significant constraints that limit the ability to connect new energy projects in the region.


Major network reinforcements are needed, such as the ongoing Bramford – Twinstead reinforcement project, to unlock clean energy potential from East Anglia. Our proposed battery site will connect directly to the new Butlers Wood substation, providing flexible services that help grid operators balance supply and demand, improve power stability, and reduce network constraints as the UK transitions away from fossil fuels.


Without storage schemes like this one, renewable generation will face increasing curtailment over the second half of this decade and beyond, and gas‑fired stations may be called upon more frequently to maintain grid stability. The Butlers Wood BESS will play an essential role in enabling a cleaner, more resilient energy future.

Zenobē engineer conducting an on-site inspection at Capenhurst’s battery storage facility.

Do you have any questions?

If you have any questions about our battery energy storage system in development contact our project management team.

If you cannot find the document you are looking for, get in touch with our project development team by emailing ukprojects@zenobe.com

Peter Smith

Head of Product

Pete leads Zenobē’s growing team of Product specialists across all areas of the business. His team oversee our R&D as well as product development in both hardware and software.

 

He has been working in the European E-Mobility sector from over ten years, specialising in the design, build and delivery of software systems for EV Charging.