Smart EV Charging Platform Cuts Customer Costs 70%, Whilst Reducing Grid Peak Demand 55%
4+ year and ongoing partnership delivers real-time power management system now scaled across multiple energy providers worldwide
Executive Summary
Kaluza, an OVO Group company, is an intelligent platform ecosystem powering the future of energy—from revolutionising billing to smart electric vehicle charging. Their technology empowers some of the biggest energy suppliers to better serve millions of customers.
The Problem
As EV adoption accelerates towards 245 million vehicles by 2030, Kaluza needed to build a smart charging platform that would optimise when and how EVs charge—reducing costs for drivers, preventing grid overload during peak times, and maximising use of renewable energy. They required rapid team expansion across multiple product squads to deliver this ambitious vision.
The Solution
Zartis scaled Kaluza’s engineering capacity from 4 to nearly 30 engineers embedded across different products and squads, bringing expertise in Go, React, Node.js, TypeScript, microservices, and cloud technologies. Our engineers played a key role in designing and implementing a real-time power management system for smart EV charging.
The Outcomes
- 70% reduction in EV charging costs for customers (up to £500 annually)
- 55% reduction in peak demand through intelligent charging optimisation
- 384 MWh delivered with 215 MWh (55%) shifted away from peak times
- 6.2 tonnes CO2 savings in 11-month pilot with 300 EV users
- Platform scaled globally across multiple energy providers with high EV market coverage
An OVO Group company, Kaluza is an intelligent platform ecosystem, powering the future of energy. From revolutionising billing to smart electric vehicle charging,
Kaluza’s technology is empowering some of the biggest energy suppliers to better serve millions of customers.
Kaluza’s platform addresses one of the energy sector’s most critical challenges: managing the massive electricity demand from the global EV fleet whilst transitioning to renewable energy.
Their market leading innovation is recognised across the industry, winning ‘Technological Innovation’ in edie’s Sustainability Leaders Awards 2020, ‘Transport Technology’ in BusinessGreen Technology Awards 2019 and ‘Best Innovation in Electricity’ at the UK Energy Innovation Awards 2019.
The EV Infrastructure Problem
By 2030, over 245 million electric vehicles will be on the world’s roads as countries accelerate net-zero transitions. This growing fleet will account for significant global electricity demand, creating both challenges and opportunities:
The grid capacity problem
Most EV drivers charge overnight at home, but if everyone plugs in when they arrive home (around 6pm)—when both demand and carbon intensity are already highest—the grid faces massive peak load issues. In reality, EVs only charge for 19% of the time they’re plugged in at home, providing opportunity to shift demand away from peak times.
The cost problem
Without smart charging, EV owners face high electricity bills from charging during expensive peak periods. This increases the total cost of EV ownership, potentially slowing adoption.
The sustainability problem
Charging during high-demand periods means using energy from fossil fuel “peaker plants” rather than clean renewables, undermining the environmental benefits of EVs.
What Kaluza Needed
Kaluza needed to build a platform that could:
- Intelligently manage when EVs charge based on grid capacity, energy prices, and renewable availability
- Reduce costs for EV drivers to accelerate adoption
- Prevent grid overload by shifting demand away from peak times
- Maximise renewable usage by charging when clean energy is abundant
- Scale rapidly to support major energy suppliers serving millions of customers
Why Traditional Approaches Weren't Working
Hiring challenges in competitive market
Kaluza needed senior engineers with expertise in modern cloud technologies (Go, React, Node.js, TypeScript, microservices) who could contribute immediately. Traditional hiring in the competitive UK tech market would take 6+ months per role.
Needed experienced remote-first teams
As a distributed organisation, Kaluza required engineers who could operate effectively in remote, collaborative environments from day one—not just technically skilled but experienced in remote working practices.
Multiple simultaneous product initiatives
With various products under development simultaneously (billing platform, smart charging, energy optimisation), Kaluza needed flexible team scaling across different squads rather than a monolithic team structure.
Why They Chose Zartis
To deliver this vision, Kaluza asked our help to:
- Rapidly expand engineering capacity across multiple product squads
- Build real-time optimisation algorithms processing market data, telemetry, and user preferences
- Integrate with leading EV manufacturers and charging equipment providers
- Design resilient microservices architecture handling millions of charging events
- Implement DevOps practices for reliable, continuous deployment
how we worked together
The Zartis Approach
Cross functional teams working across multiple products and squads
Rapid team scaling (2019-present):
Zartis was able to quickly hire 4 engineers with the required skills in the initial deployment, significantly increasing the capacity of one of Kaluza's teams in a short span of time. Since 2019, our team has expanded to nearly 30 engineers working across different products and squads. This distributed team spans multiple European locations including Spain, Italy, Romania, Greece, Portugal, Hungary, Poland, the UK, France, and Croatia, bringing diverse perspectives and expertise to Kaluza's technology initiatives.
Embedded squad model
Zartis engineers integrated directly into Kaluza's product squads as full team members, not external contractors. Our engineers participate in daily standups and sprint planning, contributing to product development and architecture decisions alongside Kaluza's internal teams. This embedded approach means Zartis engineers are actively involved in technical debt reduction initiatives, proof-of-concept exploration, and DevOps and infrastructure improvements, ensuring they're true partners in Kaluza's technology evolution.
Remote-first collaboration
Zartis engineers brought valuable expertise in effective remote working, helping establish highly efficient processes and workflows optimised for remote collaboration. Working together, Zartis and Kaluza developed optimised communication processes ensuring transparency across distributed teams, implemented asynchronous collaboration workflows that accommodate different time zones and working styles, and established documentation practices for remote knowledge sharing that keep everyone informed and aligned.
Knowledge transfer & upskilling
Beyond delivery, Zartis engineers actively share expertise across a range of cutting-edge technologies. This includes modern frontend frameworks like React and TypeScript, backend microservices patterns using Go and Node.js, and event-driven architectures powered by Kafka. The team also transfers knowledge in cloud-native infrastructure approaches and test automation and quality assurance practices, continuously raising the technical capabilities of the broader Kaluza engineering organisation.
Our approach
What We Delivered
The platform leverages a modern technology stack including React, Node.js, TypeScript, Go, and Python for application development, with GraphQL for efficient data querying and Kafka powering event-driven microservices architecture on cloud infrastructure. The system’s architecture combines real-time optimisation algorithms with multi-OEM integration abstraction, processing millions of charging sessions at scale—having delivered over 384 MWh in the pilot phase alone and now scaled across multiple global energy providers. At its core, the innovation centres on real-time power management that intelligently combines electricity market data, vehicle telemetry, and sophisticated optimisation algorithms to deliver smart EV charging that’s both cost-effective and environmentally sustainable.
Integration with EV ecosystem
- Connectivity established with leading Electric Vehicle Supply Equipment (EVSE) manufacturers—the physical chargers
- Direct integration with Auto OEMs (vehicle manufacturers) via their telematics APIs
- Real-time telemetry data collection from both vehicles and charge points
How it works: Telemetry data gathered from OEM APIs feeds the optimisation engine, which then sends commands (START, STOP, CHARGE-SCHEDULES) back to vehicles via established integrations.
Key telemetry attributes captured:
• State of Charge (SoC): Current battery level determining how much energy needed
• Battery Capacity: Total storage (kWh) and usable energy limits for charge calculations
• Rate of Charge (RoC): Current power delivery allowing real-time throttling or ramping
• Driver Preferences: User-defined schedules ("Charge by 7am", "Only use solar energy")
• Plug-in/Plug-out Events: Real-time connection status triggering optimisation start/stop
• Location Context: Current location and charger type determining charging eligibility
Real-time algorithmic optimisation
Optimisation algorithms integrate multiple data sources:
• Wholesale electricity pricing in real-time
• Grid carbon intensity data
• Tariff structures including Distribution Use of System (DUoS) charges with time-of-day zones:
• Red zone (4pm-7pm): Peak—most expensive
• Green zone (night): Off-peak—cheapest
• Amber zone: Mid-rate periods
• Device-level inputs: Consumer preferences, battery state, weather forecasts
• Renewable generation forecasts
Smart scheduling: When a customer plugs in their vehicle at 6pm (peak time), the platform automatically schedules charging during lowest-cost, greenest periods overnight—ensuring the vehicle is ready by morning without driver intervention.
"Set it and forget it" mobile app
• Separates EV charging costs from household electricity usage
• Credits customers monthly for optimised charging savings
• No manual monitoring of energy prices or charging times required
• Transparent reporting showing when charging occurred and savings achieved
Driver control: Users maintain override capability if immediate charging needed, balancing automation with user autonomy.
Transforming telemetry into intelligence
• Real-time dashboards tracking device behaviour and market conditions
• Programme impact analysis measuring demand shifting effectiveness
• User behaviour insights enabling continuous optimisation improvements
• Predictive analytics for grid capacity planning
Our approach
Key Technical Decisions
Event-driven microservices architecture
Built on Kafka-based event streaming, enabling real-time processing of millions of charging events whilst maintaining system resilience. This architecture allows independent scaling of optimisation, telemetry processing, and integration services.
Multi-OEM integration strategy
Rather than building for a single manufacturer, the platform was designed to integrate with multiple Auto OEMs and EVSE providers simultaneously. This maximised market coverage but required flexible abstraction layers to handle varying API capabilities.
Optimisation-first design
The platform prioritises intelligent scheduling over simple “charge now” functionality. Algorithms continuously evaluate trade-offs between cost, carbon intensity, user preferences, and grid constraints—making thousands of micro-decisions per charging session.
Cloud-native infrastructure
Leveraging modern cloud technologies (microservices, containerisation, serverless functions) enabled rapid scaling as the platform expanded from pilot to production across multiple energy providers.
Gradual rollout with pilot validation
Rather than launching at full scale, Kaluza ran an 11-month pilot with 300 users to validate the approach, measure outcomes, and refine algorithms before broader deployment.
the results
Measurable Improvements in
Cost, Carbon, and Grid Stability
Pilot Study Results (11-Month Trial, 300 EV Users)
The platform participated in a trial led by a leading UK Distribution Network Operator (DNO), delivering measurable impact:
Peak demand reduction:
Reduction in EV demand at peak times comparing smart charging vs. unmanaged charging
- Both trial groups (red band and amber band) exhibited evening peak reduction around 55%
- Successfully shifted charging away from 4pm-7pm when grid demand and costs are highest
Energy delivery & carbon impact
total energy delivered
- 215 MWh (55%) shifted to off-peak, lower-carbon periods
- 6.2 tonnes CO2 savings achieved through optimised charging patterns
Production Deployment: Customer Cost Savings
Following pilot success, Kaluza launched a special energy tariff separating EV charging costs from home electricity:
Customer financial impact:
Reduction in EV charging costs for customers
($617) annual savings per customer
- Low, flat rate for EV charging independent of household energy use
- Monthly credits for electricity savings via smart charging
How it works:
Customers pay a separate, lower rate for EV charging whilst household electricity remains on standard tariff. Platform automatically optimises charging and credits customers for avoided peak-period costs.
Platform Scale & Market Position
The platform quickly got recognised and gained international attraction, which opened the route for greater scaling.
Global expansion:
- Scaled across multiple energy providers worldwide
- High EV market coverage through direct integrations with most major manufacturers
- Proven robustness handling millions of charging sessions
Technical maturity:
- Reliable infrastructure supporting 24/7 real-time optimisation
- DevOps practices enabling continuous delivery of improvements
- Test automation ensuring quality across rapid iteration cycles
What This Enabled Next
Foundation for future innovation and new capabilities:
Vehicle-to-X (V2X) Technologies:
This turns EVs from one-way energy consumers into two-way grid participants. Bidirectional charging means your EV battery can power your home during blackouts (V2H), sell electricity back to the grid during peak demand (V2G), or function as part of a distributed battery network that helps balance the entire electricity grid whilst earning money for owners.
Expanding Platform Capabilities:
The architecture Zartis and Kaluza built can extend beyond basic smart charging to coordinate with home solar panels and battery storage, optimise charging for commercial vehicle fleets, use machine learning to predict user behaviour and grid conditions, and implement real-time pricing models that respond instantly to market changes—all without requiring a system rebuild.Retry
Continued Partnership
The 4+ year collaboration continues with Zartis engineers embedded across evolving product initiatives, demonstrating sustained strategic partnership rather than transactional staff augmentation.
Building the Energy Transition?
If you’re scaling clean energy technology and need senior engineering talent who can contribute from day one, Zartis delivers embedded teams with deep expertise in modern cloud architectures, real-time systems, and distributed platforms.