Achieving net zero is now a defining challenge for organisations with large operational footprints particularly those that rely on vehicle fleets, distributed estates, and high reliability field services. These businesses face more complex barriers than office based organisations, yet they are also among those with the greatest opportunity to drive real-world carbon reductions.
Marston Holdings has spent the past several years reducing its emissions across fleet operations, buildings, supply chains and digital processes. Through fleet electrification, phasing out natural gas, installing on-site solar generation, and shifting to digital-first working methodologies, the organisation has begun transitioning to a low-carbon operating model that maintains service reliability while reducing
environmental impact.
This article shares practical insights from that journey—insights intended to help public-sector partners, utilities, and other operational organisations plan their own credible, science-aligned decarbonisation pathways. The lessons are not theoretical; they are grounded in real deployment, real challenges, and real emissions reductions.
Why Fleet and Estate-Based Organisations Need a Different Route to Net Zero
Many corporate net-zero roadmaps assume a relatively simple operational footprint: office spaces, predictable energy consumption, and limited transport requirements. For organisations that operate extensive fleets, varied property portfolios, and high-tempo field services, the reality is very different.
Key features of these complex operational environments include:
- Vehicles that operate long hours, across dispersed geographies, in time-critical roles
- Specialist or technology-equipped vehicles with non-standard energy demands
- Offices and depots of varying age, efficiency, and ownership status
- A need for 24/7 service reliability regardless of weather, grid constraints, or infrastructure challenges
- A dispersed workforce where behavioural change is harder to implement at scale
At the same time, external expectations on suppliers and field-service organisations are rising. Local authorities, utilities, government agencies, and corporate clients are demanding credible net-zero pathways from their delivery partners, often as a prerequisite for contract award or renewal.
For these organisations, decarbonisation is not optional—it is operationally and commercially fundamental.
Understanding the Carbon Baseline: Insights from Marston’s Footprint
Typical emissions profile for a field-service organisation:
- Fleet fuel consumption (Scope 1): Often the single largest emissions source
- Building energy use (Scope 1 & 2): Gas boilers, ageing HVAC, lighting
- Purchased goods & services (Scope 3): IT equipment, enforcement tech, uniforms, etc.
- Subcontracted services (Scope 3): A critical but harder-to-measure category
- Employee commuting and travel: A notable contributor, especially across dispersed sites
Collecting high-quality fleet and energy data was a crucial early step. Telematics and fuel records helped pinpoint inefficient driving patterns, underutilised vehicles, and opportunities for electrification. Building energy audits identified the highest consuming sites and highlighted quick-win interventions.
The lesson is simple but powerful: you cannot decarbonise what you cannot accurately measure.
Fleet Electrification: From Early Trials to Scaled Deployment
For Marston, the fleet represents one of the most significant opportunities for carbon reduction. However, electrifying a high-utilisation operational fleet is very different from swapping company cars for EVs.
The Unique Challenge
- Long daily mileages, often without fixed routes
- Vehicles carrying cameras, ANPR technology, tablets, and communications equipment
- Staff working across unpredictable environments
- Some depots without adequate grid capacity for multiple chargers
- Barriers to infrastructure modification
These constraints required a phased, evidence-led approach.
Trials and Evaluation—A Data-Driven Method
Marston conducted real-world EV trials across different operational teams and regions. This helped evaluate:
- Actual range under full operational load
- Charging patterns and downtime
- Driver experience and concerns
- Suitability for specialist equipment
Telematics provided granular insights—particularly regarding energy consumption per route type and driver behaviour. This ensured that EV rollout was based on real operational data rather than assumptions.
Charging Strategy
Reliable charging infrastructure is essential for fleet electrification. Marston pursued a mixed approach:
Workplace charging
- Installation of chargers at key depots and offices
- Load balancing strategies to avoid grid overload
- Assessments of future demand for multi-vehicle charging
- Collaborative client planning to ensure harmonious infrastructure development
Public charging as contingency, not strategy
- Mapping high-quality public chargers along typical routes
- Using them only when essential to avoid operational downtime and increased costs
Cultural and Behavioural Change
Fleet electrification is as much about people as it is about technology.
Key steps included:
- Training staff on EV driving techniques
- Addressing range anxiety with clear messaging and telematics dashboards
- Encouraging route planning that aligns with charging opportunities
- Embedding EV-specific vehicle checks
This cultural shift has been central to maintaining service reliability while reducing
emissions
Results and Carbon Reductions
Early outcomes for EV-deployed teams show:
- Significant CO₂e reductions per vehicle
- Reduced fuel costs
- Lower maintenance requirements
- Positive driver feedback
- Improved noise and local air-quality impact in residential and urban areas
The transition continues, with an increasing proportion of the fleet moving to electric as technology improves and operational insights grow.
Decarbonising Buildings: Phasing Out Natural Gas and Deploying Solar PV
Fleet emissions are critical—but buildings represent a substantial share of the carbon footprint for field-based organisations. Marston’s estate includes depots, offices, and multifunctional properties, many of which were built before modern efficiency standards.
Gas Phase-Out Strategy
Transitioning away from fossil-fuel heating involved:
- Replacing ageing gas boilers with efficient models
- Phasing out gas-heated properties from the portfolio
- Data-driven portfolio consolidation
- Improving insulation and building fabric
- Upgrading HVAC systems
- Deploying smart thermostatic controls and automated shutdown policies
- Conducting “deep dive” audits on the least efficient buildings
This layered approach allowed improvements even in older, leased, or complex properties.
Smart Energy Management
Efficiency upgrades have included:
- LED lighting and occupancy sensors
- Time controls for lighting and HVAC
- Digital energy monitoring across buildings
- Building-use optimisation
These measures deliver fast payback periods
and meaningful emissions reductions.
Installing Solar PV
Several sites now include rooftop solar generation, which:
- Reduces Scope 2 emissions
- Provides energy during daytime operational hours
- Lowers electricity costs
- Supports future fleet charging demand
Solar installations have been particularly successful where electricity demand aligns with site operating hours.
Digital First: Cutting Carbon Through Operational Efficiency
Decarbonisation is not solely about replacing technologies—it also requires rethinking how services are delivered.
Marston has reduced operational emissions through:
Digital Engagement
- Increased use of email, and online platforms
- Reduced inter-site postal correspondence and visitation
- Lower operational travel demand
Digital Case Management and Paper Reduction
- Minimising paper use and storage
- Eliminating legacy printing where possible
Smarter Scheduling and Routing
- Using data-driven algorithms to reduce mileage and idle time
- Optimising staff deployment to reduce unnecessary travel
- AI-driven route optimisation
These digital-first measures not only reduce emissions but also enhance service efficiency.
Sustainable Procurement and Supply Chain Influence
As a large public-sector supplier, Marston recognises its ability to influence upstream and downstream emissions.
Efforts include:
- Integrating carbon performance into procurement frameworks
- Encouraging subcontractors to adopt low-emission vehicles and strategies
- Working with technology providers to reduce embodied carbon
- Prioritising suppliers with verified environmental credentials
- Embedding environmental KPIs into long-term contracts
- For many clients—especially local authorities—this supply chain influence is as important as direct emissions reductions.
Practical Recommendations for Organisations with Similar Operational Footprints
Drawing on Marston’s experience, the following recommendations can support other organisations in fleet-based or multi-site sectors.
For Fleet-Operated Businesses
- Start small: run controlled EV trials
- Use telematics before making major investments
- Build charging infrastructure ahead of vehicle rollout
- Train drivers, managers and operations in EV-aware planning
- Document lessons and iterate
For Multi-Site Estates
- Conduct phased building audits
- Prioritise efficiency measures with the fastest payback
- Introduce solar PV wherever structurally and financially suitable
- Negotiate lease terms that support energy improvements
For Executive Teams
- Set interim net-zero targets that are achievable
- Review carbon performance quarterly (at least!)
- Ensure sustainability is embedded in procurement
- Invest in both technology and cultural change
- Communicate progress with transparency
The Road Ahead: Opportunities for the Next Phase
Marston’s decarbonisation journey is ongoing, with several priorities for the coming years:
- Completing fleet electrification as technology for long-range and specialist vehicles improves
- Expanding solar PV across additional depots and buildings
- Evaluating battery storage for local energy resilience
- Increasing use of AI for route optimisation and predictive fleet management
- Continuing the phaseout of gas heating
- Strengthening Scope 3 measurement and supplier engagement
- Collaborating more deeply with clients to co-design low-carbon service models
The path to net zero requires continual improvement, innovation, and close partnership with the public bodies served.
CONCLUSION
Decarbonising a complex operational organisation is challenging—but achievable, replicable, and commercially advantageous.
By combining fleet electrification, building energy improvements, digital transformation, and supply chain influence, Marston Holdings has begun to demonstrate how service reliant organisations can move meaningfully toward net zero while maintaining reliability and client satisfaction.
The transition is not driven by a single technology or initiative. It requires a multi-layered, data-driven approach supported by cultural change, investment, and long-term planning.
The message is clear: complex organisations can deliver net-zero pathways that align with climate science—while improving efficiency, reducing costs, and supporting clients’ own net-zero ambitions.
