UK Energy ERP Legacy Displacement and Invoice Generation Platform
Overview of Our Client
Our client was the UK branch of a large European company operating in the energy market. The organization relied on a legacy approach for accumulating energy-related data, performing business calculations, and generating customer invoices using Excel. Their existing solution was slow and could not handle the growing volume of data. Furthermore, it did not allow for rapid adaptation to changing regulatory requirements.
As part of its legacy displacement initiative, the company needed to gradually replace the existing system with a modern solution but maintain uninterrupted business operations. An additional challenge was the use of multiple Excel files containing business logic that had to be incorporated into the new application.
SCAND was engaged to participate in the modernization project, covering business analysis, solution architecture, data migration, development, integration, and gradual replacement of the legacy functionality.
- Region: UK
- Industry: Energy / Utilities
- Timeline: ~12 months
Challenge
The legacy ERP application supported critical energy-market operations, including data accumulation, calculations, and invoice generation. Replacing it required more than simply rebuilding existing functionality because the system depended on numerous external data sources and business rules embedded in Excel files. This way, the main challenges included:
- Replacing legacy functionality without disrupting ongoing business operations
- Accumulating energy consumption and transaction data from more than 50 external sources
- Incorporating business logic previously maintained in various Excel files
- Maintaining high accuracy across complex energy-market calculations
- Migrating existing customer and business data to the new platform
- Supporting invoice verification before invoices were sent to customers
- Integrating multiple UK energy-market data providers and systems
- Operating within strict corporate security and delivery constraints
- Organizing the project into several sub-projects that could be developed simultaneously
- Gradually moving users from the legacy application to the new system while maintaining business continuity
Main Goals
To modernize the client's UK energy ERP functionality, the project focused on the following objectives:
- Replace critical legacy ERP functionality with a modern application
- Centralize data collection from 50+ energy and transaction data sources with different fetching schedules, using multiple types of integration (API, email, files)
- Reproduce and automate business calculations previously supported by Excel
- Generate customer invoices automatically in the background
- Provide operators with the ability to review and verify invoice results before invoice generation
- Implement specialized modules for gas data allocation, reporting, and volume calculation
- Establish a structured data migration process
- Maintain continuous system availability during the legacy displacement process
- Provide a scalable architecture for further modernization of the client's energy-market operations
- Adhere strictly to the corporate security standards.
Project Overview
SCAND engineers participated in the legacy displacement project by developing a modern application for accumulating energy-market data, performing calculations, and generating invoices.
A key part of the project was preliminary business analysis. Before development began, the team analyzed existing requirements and business processes, designed the overall solution architecture, and prepared a data migration plan.
The project was divided into several sub-projects so that different areas of functionality could be developed simultaneously.
Particular attention was given to calculation accuracy. The new solution had to reproduce complex business rules and calculations while replacing logic that had previously been distributed across the legacy system and Excel files.
To minimize migration risks, the team applied a parallel systems legacy displacement approach. A new server was deployed alongside the legacy environment, and new functionality was progressively delivered in three-week development sprints.
Solution
The completed solution was a modern energy-market ERP platform for collecting data, performing gas and energy calculations, generating invoices, and producing operational reports.
The platform consolidated data from more than 50 sources and automated multiple stages of the calculation and billing workflow. It also provided dedicated modules for comparing transaction data, allocating unidentified gas, calculating aggregated gas reports, and determining gas volumes for producers and shippers.
The parallel deployment approach allowed the new functionality to be introduced gradually while the legacy system remained available, supporting business continuity throughout the modernization process.
Core Platform Capabilities
- Energy Data Accumulation: Collected power consumption and other energy-market data from 50+ external sources.
- External Data Integration: Integrated sources and systems including RegmanApi, Neta reports, Elexon, Endur, N2EX, EPEX, NationalGrid, and Genus Data. The supported integration types: open and closed API’s, email letters, files.
- Customer Data Migration: Migrated customer data to the new cost-effective solution, generating savings of $12,000 per year on database only
- Custom formulas support: Solution supports a custom calculation formulas builder that extends the flexibility of the product.
- Automated Invoice Calculation: Performed background calculations required for customer invoicing.
- Invoice Generation: Generated customer invoices as PDF documents after completing the required calculations.
- Invoice Verification: Allowed application operators to review and verify intermediate invoice results before delivery.
- Transaction Data Comparison: Compared gas transaction data from Xoserv with Genus/INV data after invoice generation.
- UIG Data Allocation: Provided functionality for allocating unidentified gas (UIG) data.
- Aggregated Gas Reporting: Calculated aggregated gas data reports including ZCO, ZRE, CFI, CCA, and GRE.
- Gas Volume Calculation: Calculated gas volumes for producers and shippers through the CVA module.
- Parallel System Operation: Supported gradual migration from the legacy environment to the new platform without interrupting business operations.
User Workflow
- Data Collection: The platform gathered energy consumption, transaction, and gas-related data from more than 50 external sources.
- Data Processing: Incoming information was accumulated, validated, and prepared for subsequent calculations.
- Energy Calculations: Business rules and formulas were applied to the prepared data for multiple customers.
- Invoice Generation: Calculated results were used to generate customer invoices in the background.
- Invoice Verification: Operators reviewed and verified invoice results before invoices were finalized.
- PDF Generation: Approved invoices were generated as PDF documents.
- Customer Delivery: Generated invoices were sent to customers.
- Additional Gas Processing: Dedicated modules performed UIG allocation, aggregated gas reporting, transaction comparison, and CVA gas-volume calculations.
Technology Stack
To support ERP modernization, energy-market data integration, complex calculations, and automated invoice generation, we used the following technology stack:
Backend
- .NET Core
Frontend/UI
- Angular
- JavaScript
- HTML
- CSS
Database
- Microsoft SQL Server
Data Integration
- REST/API-based integrations with external energy-market data sources
Source Control
- Git
Project Management
- Jira
Architecture
- Modular application architecture supporting parallel development and gradual legacy displacement
Results
The first production version was ready in 3 months. After approximately one year of active development, the project was successfully completed and transitioned into the support phase. The modernization replaced critical legacy ERP functionality for UK energy-market operations and introduced a centralized, automated platform for data processing, energy and gas calculations, invoicing, and reporting.
The solution integrated data from more than 50 sources, automated invoice calculation and PDF generation, and enabled operators to verify results before customer delivery. It also introduced UIG allocation, aggregated gas reporting, transaction comparison across Xoserv and Genus/INV, and CVA-based gas-volume calculations. Key outcomes included:
- $12,000 in annual savings through migration to a more cost-effective data solution.
- Gradual user migration and business continuity through parallel operation of the legacy and modernized systems.
- Successful transition to support, providing a sustainable replacement for the legacy platform.
Core Team
- Solution Architect: Designed the overall modernization architecture, legacy displacement strategy, and integration approach
- Business Analysts: Analyzed existing energy-market workflows, business rules, and Excel-based calculations
- .NET Engineers: Developed backend services, calculations, integrations, and core ERP functionality
- Frontend Engineers: Built Angular-based interfaces for operators and business users
- Database Engineers: Implemented SQL Server data structures, migration, and data-processing functionality
- Integration Engineers: Connected the platform with external energy-market data providers and systems
- QA Engineers: Validated calculations, invoice generation, integrations, data migration, and business workflows
- Project Management: Coordinated parallel sub-project delivery, three-week sprints, and implementation within corporate security constraints
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