Battery Energy Storage Systems (BESS)
Flexible, scalable, and fast-responding storage to optimise energy use and support decarbonisation.
What is a Battery Energy Storage System?
Battery energy storage systems (BESS) play a critical role in enabling efficient, reliable, and low-carbon energy networks. By storing electricity and discharging it when needed, BESS helps balance supply and demand, improves energy resilience, and supports the integration of intermittent renewable energy such as solar and wind.
BESS can be deployed at grid level or behind-the-meter for commercial, industrial, and utility-scale applications. They support a range of functions including peak shaving, frequency response, demand side management, and backup power.
Clarke Energy offers technology-agnostic BESS solutions as standalone installations or integrated into hybrid energy systems and microgrids. Our offering includes full EPC delivery and lifecycle support, helping organisations enhance flexibility, reduce emissions, and transition away from fossil-fuel-based backup generation.
Sustainability Benefits of BESS
Renewable Enablement
Supports higher renewable penetration by balancing supply and demand.
Energy Resilience
Provides backup power during outages and improves site-level reliability.
Emissions Avoidance
Stores excess renewable energy for use during peak demand, reducing reliance on fossil fuels and lowering associated emissions.
Why Clarke Energy for BESS Projects?
- Full EPC capability with in-house engineering, design, and project management.
- Technology agnostic - working with a range of leading battery suppliers.
- Nationwide service support and robust financial stability for long-term peace of mind.
- Proven track record in the energy sector with >10GW of global energy projects delivered.
- Integration expertise across hybrid systems including gas engines, solar and microgrids.
Discover More
Flexible Deployment Footprints
System Applications
Peak Shifting & Shaving
Demand Side Response
Black Start Capability
Flexible Deployment Footprints
Clarke Energy can deliver BESS projects at various scales, with required footprints ranging from 2,000 m² to 45,000 m² depending on energy and duration needs.
| BESS Size | Â 20MW/40MWh | 50MW/1000MWh | 200MW/400MWh | 400MW/800MWh |
| Typical Footprint | 2,000m2 | 5,000m2 | 22,500m2 | 45,000m2 |
System Applications
BESS enables a wide range of functions including peak shifting, peak shaving, demand side response, and black start. It also plays a critical role in microgrid integration and hybrid energy system optimisation.
Peak Shifting & Shaving
BESS stores electricity when prices or demand are low and discharges when costs are high, allowing for efficient energy usage and significant cost savings.
Demand Side Response
BESS supports demand side response by enabling consumers to reduce or shift consumption during peak grid periods—sometimes earning incentives from grid operators.
Black Start Capability
BESS can restore power to a site following a blackout without needing a grid signal, supporting grid resilience and system restart during outages.
BESS Site Overview
Explore a typical layout for a BESS site, built and delivered by Clarke Energy. See how each element, from batteries to switchgear, works together to deliver reliable, dispatchable power.
Distribution Network Operator (DNO) Switch Room
The room containing the DNO’s equipment at the point where the BESS connects to the public electricity network.
Ring Main Unit (RMU)
Typically 11 or 33 kV switchgear assembly used to connect multiple BESS to the same distribution network.
Power Conversion System (PCS)
Converts Battery DC voltage to AC voltage – typically 1331 V (nominal) to 690 V AC.
Batteries
The BESS (battery energy storage system). The DC Block – a collection of cells, modules and racks which store energy for when needed.
Storage
Critical BESS Spare Parts for site maintenance.
Welfare
Dedicated welfare unit providing facilities for site staff.
LV Switchgear
The electrical and protection equipment between the inverter and auxiliary loads on the BESS site.
Aux Transformer
A transformer that supplies power to the BESS site’s own equipment. It steps down MV power to typically 400/415 for site services.
33kV Switchgear
The MV switchgear that operates, protects, and isolates the BESS connection at the 33 kV network level.
Microgrid and Hybrid Energy Integration
BESS can operate in hybrid systems with other technologies like CHP, wind, solar, and thermal storage, managed via advanced microgrid controls to maximise energy use and reliability.
Electrolysis
Splits water into hydrogen and oxygen using electricity, producing green hydrogen for storage or use as a fuel.
Biogas Upgrading
Cleans raw biogas into biomethane, ready to inject into the gas grid or use as a renewable fuel.
CHP (Combined Heat and Power)
Generates electricity and useful heat simultaneously from a single fuel source, maximising overall efficiency.
Heat Pumps
Transfers heat rather than generating it directly, delivering efficient heating (and cooling) with lower emissions.
Thermal Store
Stores surplus heat for later use, balancing supply and demand across the site.
Standby Gas
Gas-fuelled generators providing backup power to maintain supply during grid outages.
Microgrid Controller
The brains of the system, coordinating generation, storage, and demand to keep the microgrid balanced and resilient.
Standby Genset
Diesel or bio-diesel generators providing reliable backup power when needed.
Solar PV
Converts sunlight directly into electricity using photovoltaic panels.
Wind Turbines
Converts wind energy into electricity, adding a renewable source to the generation mix.
Energy Storage
Batteries that store excess energy and release it on demand, supporting grid balancing and resilience.
Technical Insights
Beyond the Battery: BESS Installation Challenges
Battery technology may have matured, but BESS project complexity has not disappeared. Explore Bob Beckwith’s perspective on the engineering, integration, safety and operational challenges that shape successful energy storage deployments.
Will Sodium-Ion Batteries Disrupt the BESS Market?
Bob Beckwith, Group Applications Manager – BESS, examines the rise of sodium-ion batteries and their potential impact on BESS. Could they prove to be an industry game changer?
The New Reality of Hybrid Microgrid Controls for Data Centers
Hybrid microgrids are replacing traditional generator‑plus‑UPS models as data centers face AI-driven volatility and grid constraints. This article explains how modern microgrid controls work, why decentralised systems are more resilient, and how Clarke Energy deploys...
Applications
Comprehensive Project Development Support
Project Engineering
Electrical and mechanical engineering along with a dedicated team of computer aided design staff.
Project Management
Comprehensive project management service for the installation of your generation projects.
Project Feasibility
Feasibility studies offered for a range of services to assess the viability of your energy projects.
Engineering, Procurement and Construction
Comprehensive EPC services complimenting the supply and maintenance power generation equipment.
Latest BESS News and Case Studies
Clarke Energy Deliver 50MW Battery Energy Storage Solution for EDF Power Solutions in Stockport
Clarke Energy delivered and commissioned a 50MW Battery Energy Storage System (BESS) for EDF power solutions, located in Stockport.
Clarke Energy Appointed Principal Contractor for Third Grid-Resilience BESS Project with Field
The 50MW/100MWh BESS system at Drum Farm in Scotland, is scheduled to commence site-works in late summer 2025 and reach completion in 2026.
Enhancing Grid Resilience and Flexibility with Expansion of Hybrid Energy System in Romania
Pioneering project as one the first in Romania to hybridise battery energy storage in parallel with high-efficiency gas engines.
Frequently Asked Questions about BESS
Technical and Engineering
What is a battery energy storage system (BESS) and how does it work?
A BESS stores electricity during periods of low demand or high generation and discharges it when needed to balance supply and demand, improve resilience, and support grid stability.
What energy functions can BESS support at industrial and commercial sites?
BESS can provide peak shaving, load shifting, frequency response, demand side management, black start, and backup power.
Can BESS operate as part of a hybrid or microgrid energy system?
Yes – BESS integrates seamlessly with technologies such as CHP, solar, wind, and thermal storage to optimise performance in hybrid or off-grid systems.
What is black start capability in a BESS?
Black start allows a battery system to restore power after an outage without needing an external grid signal, enhancing resilience and energy security.
Financial and Commercial
How does battery energy storage help reduce electricity costs for businesses?
BESS reduces costs by storing energy when it is cheaper and discharging during peak tariff periods. It can also lower demand charges and enable participation in energy markets.
Can BESS projects qualify for grid incentives or demand response programmes?
Yes – BESS can participate in grid balancing schemes such as frequency response and demand side response, generating revenue or reducing bills.
Is battery storage a financially viable option for industrial and commercial sites?
Yes – when designed properly, BESS can offer strong financial returns through cost savings, improved energy efficiency, and access to grid services.
Environmental and Sustainability
How does installing a BESS support decarbonisation goals?
BESS enables higher renewable energy usage by storing excess solar or wind power and reducing reliance on fossil-fuel-based backup systems.
Can installing a BESS help eliminate diesel generator usage?
Yes – BESS can provide cleaner backup power, reducing or replacing the need for diesel generators and their associated emissions.
What sustainability benefits does battery storage offer to ESG strategies?
BESS supports ESG goals by improving energy efficiency, lowering carbon emissions, and facilitating renewable integration and energy resilience.
Operational and Implementation
What sectors commonly deploy battery energy storage systems?
BESS is used in sectors including manufacturing, data centres, utilities, healthcare, universities, mining, and grid services.
How long does it take to install a commercial-scale battery energy storage system?
Project timelines vary but typically range from 6 to 12 months depending on system size, permitting, and integration needs.
What kind of service and support is available after installing a BESS solution?
Clarke Energy provides full lifecycle support including system monitoring, diagnostics, preventative maintenance, and performance optimisation.
Ready to take the next step with your BESS project?
Clarke Energy’s regional experts can provide the insight and support you need to evaluate options and achieve the right energy solution for your business.
