Case Studies:




ESM CONNECT - Coltishall

Scottow Moor Solar Ltd is a company that was specifically created to develop the solar farms including this one near Norwich. They have extensive experience in renewable energy projects in the UK and overseas.

The site

Using the former RAF base of Coltishall, Norfolk County Council's vision was to use the land to its full potential, generating income, creating jobs and protecting the site's heritage assets. After deciding that a solar farm was the best use of the land, applications were approved and the first phase started in February 2015.

Our work

ESM Power Ltd were chosen as one of the main contractors to help realise the potential of generating enough clean energy to power around 12,000 homes and saving 20,000 tonnes of CO2 each year. Our first phase was completed within a very tight deadline and included:

• Designing and installing both the DNO and customer 33kV substations and switchboards

• Civil and electrical designs

• Procurement, installation and commissioning of all equipment

• Connecting 27MW of solar generation to the grid network

Phase two

After the successful first phase, we began phase two which included all of the ICP work and a 33kV DNO connection. We also added a further 20MW to the grid connection as well as four new circuit breakers and two switches. The four customer substations had three 500kVA transformers and another 200kVA transformer added.

ESM Power worked with several contractors as well as using our own resources to complete the work and saw us responsible for the LV changeover as well as all commissioning, cable installations, terminations, and excavations.

The site also presented challenges we had to overcome, including contamination from asbestos and obstructions underground from existing services.

We were delighted to work on this major clean energy project. The scheme involved an imaginative design solution to enable the connection of five separate 5MVA solar parks to the same point.



ESM CONNECT - Troughton Solar Farm

The site

Covering around 100 acres, this flat site powers over 7,500 homes and saves 10,750 tonnes of CO2 emissions every year.

Our work

ESM Power Ltd was chosen for the design, procurement and construction of a new 132kV sub-station to accommodate the 25MW export to the point of connection on Western Power Distribution (WPD) network. Design commenced in February 2015 with construction starting in August 2015 and completed in March 2016. The wet weather in late winter was a particular challenge but we overcame all obstacles to get the project completed on time. Among a range of works, we carried out the following design, build, commission and handover to the DNO:

•   A detailed civil and electrical design to WPD's specifications for the 132kV metered substation and private substation

•   Earth resistivity testing and earthing design

•   Supply and construction of the support structure for the surge arresters and three disconnectors 

•   Supply and installation of a 132kV metered circuit breaker, a 132kV to 33kV 25/30 MVA distribution transformer complete with a 33kV three-panel switchboard 

•   Supply and installation of a 50/100kVA auxiliary transformer 

•   Directional drill under the M5 motorway as part of the cable route 

•   Full commissioning including G59

This connection is ESM Power's second 132kV site and has added 25MW of solar connection to our portfolio.




Ruskin Square is a large mixed development, located in the heart of Croydon's central business district. The project includes residential units, shops, cafes, restaurants and appealing public spaces. There will also be fast and easy access to central London as well as excellent public transport connections.

Our work

We are contracted with the developer, Stanhope Plc who have over 30 years of experience and an impressive track record. Stanhope Plc chose ESM Power Ltd to provide a connection of 16.4 MVA, 11kV supply to Ruskin Square.

Work began in 2013 and will continue over the next 10 years as the site is developed in stages to include four residential buildings which are all low voltage (LV) metered and five commercial buildings which are all high voltage (HV) metered.

To date, ESM Power has provided the following:

• A temporary building supply connection for residential number 1 development

• Three 11kV circuits to the main site from UKPN Croydon Central Substation

• 11kV supply to the first residential development

• A temporary building supply to building number 3

• 11kV supply to the second residential development and box park

For the initial phase of the development, we provided a temporary building supply by installing a UKPN approved ring main unit and a private customer transformer which was energised in March 2014.

The permanent supply to residential number 1 involved the connection of three 11kV feeders to the site into a UKPN approved trunk feeder unit.

A UKPN approved unit substation was also installed, consisting of a Schneider 1000kVA unit transformer utilised to provide the LV cut outs to the residential building.

Main supply and tram crossings

The point of connection for the main supply was an existing UKPN substation at Croydon Central. To provide the 16.4MVA capacity, three underground 11kV circuits were required. This involved trenching through highway, footpaths, and three tram crossings through central Croydon, using a technique called 'pipe jacking'.

For one tram crossing, we had to close an existing subway station and construct a steel piped box section through the subway.

The project has involved us working with main contractors and a wide range of professional teams including MEP consultants, architects and cost consultants. We are excited to continue with this major development and look forward to seeing Ruskin Square's vibrant new image.



ESM DESIGN - Clee Meadows

Phase 1 of the development was completed first which involved 49 domestic plots, a total of 184 plots, 76 flats & 7 retail units are to be built across the whole development. The design element for this project consisted of gas, electric and water and our work began with the preliminary electrical drawings. These drawings were sent to the client who awarded us the job and our in-house electrical design team took over.

Who was involved?

With instruction from the design manager, our design engineer's first step was to apply for the required electrical load for the site from the local distribution network operator (DNO). This was Northern Powergrid (NPG) and after receiving all of the information from the client, the ordnance survey map was purchased and the drawings started to come together.

The design process

With this project, the Independent Distribution Network Operator (IDNO) adopted the low voltage electrical portion of the site which includes the 315kVA transformer, feeder cabinet, low voltage cables and joints including the cut-outs located within the meter boxes attached to each property. The DNO adopted the high voltage side which included the high voltage cables, terminations and ring main unit. Each network operator has their own standards which ESM Power adhered to throughout the design process.

As each operator adopted different assets, we also produced individual drawings to suit their needs. We ensured that we had approval back from both sides before any works commenced on site.

After receiving approval from the IDNO and DNO, the drawings were then updated for construction and issued to both the client and the team within ESM Power to allow the project to advance to the next stage.



ESM DESIGN - Follingsby

The Client

Legal & General UK Property Fund are a multinational financial services group. Their services include investment management, general insurance, life insurance, pensions and building services.

Our Work

The client requested ESM Power's services to assist with an upgrade of 7MVA to feed into new developments in Follingsby Business Park.

ESM Power are acting as principal designer and principal contractor for this project. The first stage was completed off site and included approximately 3km of cable route, the majority of which was alongside the A194 road.

The design stage of this project was a particular challenge. We encountered major obstacles such as roundabouts, high areas of congestion and railway bridges as well as restrictions from Highways Agency and Northern Powergrid. To complete the route and overcome these challenges, we used a number of complex directional drills. Several of these were the deepest and longest that Northern Powergrid have ever experienced and so obtaining design approval proved difficult. ESM Power's designs were based on both the IDNO and client requirements and we successfully obtained design approval from UKPD as the adopting asset owner for the network.

The second stage was on-site work. The majority of the route, approximately 2km, was carried out in the adoptable roads and footpaths. ESM Power have supplied and installed a number of ring main units, transformers and low voltage breakers to feed the units.

We have also carried out all of the civil works both on site and off site, including plinths and excavation work.

This project required all areas of our business to work together and communication was a contributing factor to successfully completing the initial stages. We provided all correspondence to the local council and Highways Agency, seeking all the required works notices and permissions. Also we dealt with all construction health and safety, acting as principal contractor and notification to HSE.



ESM NETWORKS - EnviroEnergy

EnviroEnergy are one of the UK's longest established district heating companies. They manage energy production, supply and billing for both domestic and commercial properties across the city of Nottingham.

The site

Owned by Nottingham City Council, EnviroEnergy's London Heat Road Station supplies power to 4,700 homes and 100 businesses across Nottingham. This includes some of the city's biggest attractions such as the Victoria and Broadmarsh shopping centres and the National Ice Centre Arena as well as vital services at Nottingham Trent University and HM Revenue and Customs.

The work

The existing switchgear was approaching the end of it's useful operational life, oil filled and subject to numerous Suspensions of Operational Practices (SOPs). ESM Power replaced it with modern SF6 equivalent units.

This work provides the site and the services powered by this substation with long-term security of supplies. What's more, the site has now regained the flexibility of being able to switch local circuits safely without the inconvenience of switching upstream.

With careful planning ESM Power engineers worked through the night to minimise disruption to the ongoing site operations.



ESM DESIGN - Wood Wharf

A new residential led, waterside site is being developed in Wood Wharf. This major estate will have over 3,400 domestic plots, 20 high rise buildings and over 45MVA of commercial load.

Wood Wharf is one of central London's largest privately owned development sites covering 23 acres and is of major importance on a local, national and international level.

Our Work

ESM Power were successfully awarded the project after providing the Canary Wharf Contractor with confidence in our technical understanding as well as offering a competitive commercial contract.

This major project included five High Voltage (HV) supplies from Deptford Primary, Blackwall Way and Simpsons Road. We provided the customer with a diversified capacity of 51MVA.

The 11kV supply had to be cleverly integrated into newly established onsite 11kV switchgear panel boards to allow for a secure supply to the entire development.

Due to the nature of the project, there were many technical hurdles to address and resolve, including:

• Basement substations with long plant and indirect plant replacement routes

• Substation proximities to residential and commercial buildings

• Complex DNO and IDNO HV and LV routes, including bespoke chambers and shared access agreements

• Producing a design to assist with spreading the load across the main HV supplies while maintaining the level of security required

• Internal trades and utilities interface

• High rise LV distribution

• Over 20 HV integral substations 

To overcome some of these challenges, our expert design team delivered a personable design service including turnkey design solutions to suit the client, DNO and IDNO standards.

We also had the responsibility of appointing a suitable IDNO to adopt the LV network and parts of the HV network. ESM Power carried out extensive research and negotiations before appointing LEEP. Our approach to this task further maintained the client's confidence in our abilities to protect their interest whilst ensuring the adoptability of the scheme.

ESM Power managed site M&E contractors delivering the adoptable scheme. What's more, we put in place reasonable processes to ensure the sub-contractors are delivering to a high standard and meeting our high safety and quality standards as well as the client, DNO and IDNO expectations.

Our experience with installing complex HV and LV networks means we have also been appointed to deliver Block E (phase 1) including 2no HV substations and an extensive internal LV network.



ESM CONNECT - Sherford

The site

Sherford Primary

The project

To carry out the electrical design, installation and project management of the 33/11kV substation build at Sherford Primary. The project is to support the load for a new development here which will include:

• 5,550 high-quality new homes

• 84,000 square metres of commercial and retail area

• A wide range of community facilities

Our work

Work on this project consisted of many different elements including two new 33/11kV (12/18 MVA) transformers, 33kV switchgear, 11kV switchgear, protection panels, substation earthing and all other works associated with a new primary substation. We also acted as the main principal contractor with responsibility of managing the project in line with CDM regulations including planning, managing, and monitoring all risks on site. We worked with several contractors as well as our own and we ensured that all contractors followed our rigorous safety rules and were aware of all risks. This stringent approach contributed to the success of the project without any reported injuries or accidents.

This site itself was a particular challenge because of the access down a narrow lane. This proved difficult when delivering the transformers and switchgear but ESM Power overcame these obstacles to complete the project in time.

The new primary substation has a shared building with dedicated rooms and contains equipment owned and operated by Western Power Distribution (WPD) and GTC as the IDNO.



ESM CONNECT - Thirty Acres

Enerparc is a global expert in large-scale photovoltaic (PV) systems. They deliver reliable and economical solar power to a variety of customers.

The site

The Thirty Acres Solar Farm site delivers 3MW of power.

Our work

ESM Power Ltd commenced design work in November 2015 with construction on site beginning in February 2016.

Construction was completed a month later in time for the March solar tariff deadlines. This was within an extremely tight deadline, our work included the design, procurement and construction of a 3MW supply to the new solar farm from an 11kV point of connection on Western Power Distribution (WPD) network.

The site required an innovative approach, crossing an old bridge structure in order to utilise steel ducts to protect the cables due to shallow depth.
Our main work included:

• A detailed civil design to WPD specifications for the 11kV metered substation

• Supply and installation of the dual customer/DNO substation GRP building and associated earthing

• Supply and installation of 11kV metered RMU for the substation and metering equipment

• Manage the adoption agreement

• Full commissioning including G59



ESM CONNECT - West Raynham

The site

The 225-acre site at West Raynham is a former RAF station and was chosen due to its reputation as being one of the sunniest places in the UK. The farm aims to power more than 14,000 homes for the next 25 years and ESM Power was chosen as the principal contractor, beginning the first phase of connection in September 2014.

Our work

In a six-month period from September 2014 to March 2015 we completed both the physical build of the 132kV/33kV substation and the 9km 33kV cable route to the solar farm.

ESM Power designed, procured, installed and commissioned the high voltage infrastructure to the solar farm. We managed the 132kV point of connection (POC) interface on behalf of the client with UK Power Networks. As the ICP, we also undertook the contestable element of the 132kV works to UKPN standards.

The site features around 200,000 solar panels producing 49.9MW.



ESM CONNECT - Stainforth

The site

151 plot housing development on Briars Lane in Stainforth, Doncaster. Work commenced in July 2017 and will be an ongoing project.

The Client

Owner and developer, RoadGaz Group will be constructing new build properties in Stainforth, Doncaster and have awarded GS Energy Connections the job to complete the electrical, water and gas connections to the properties. As specialists in water and gas, GS Energy Connections have assigned ESM Power the electrical part of the project due to our expansive knowledge in the area.

Our Works

ESM Power's work on the project consists of installing a new substation to supply the site with the required load for the properties. The substation will be connected to the local network by high voltage cables and these will then go on to be adopted by the local distribution network operator, Northern Power Grid.

Within the brick built substation enclosure we installed a 315kVA package substation which included a ring main unit, 315kVA transformer that will step down the voltage from 11,000V to 433V and a low voltage cabinet which allows the low voltage cables to run out through the site. These will then be separated further to allow each property to be connected individually with its own electrical supply - the same applies for the water and gas.

We will be staging design and construction throughout the phasing of this ongoing project. The first phase consisted of 43 plots, including 4 initial show homes, which the developer requested to be connected first in order for potential buyers to see how each property was laid out. ESM Power will continue to work with the client to deliver connections to different properties including flats and houses.



For more information on any of our services, quotations or general enquiries, contact ESM Power.