Solar EPC (Engineering, Procurement, and Construction) contracting is a project business. Revenue comes in milestones, costs accumulate daily across materials and labour, and every project runs simultaneously with four others each at a different phase, each with its own procurement, its own crew, and its own client chasing updates.
Most solar EPC companies in Pakistan manage this through a dangerous combination: WhatsApp groups for site coordination, Excel files for project budgets, a separate accounting system for invoicing, and a manual process for equipment tracking. The result is cost overruns that only surface at project close, materials dispatched to the wrong site, milestone invoices delayed because finance does not know installation is complete, and equipment warranties that cannot be traced to specific projects.
Odoo ERP unifies the entire solar EPC workflow from client survey through procurement, installation, commissioning, and handover in one system where every cost, every serial-numbered piece of equipment, and every milestone is linked to the project it belongs to.
The Four Layers of Solar EPC Complexity
- Multi-project parallel execution: A growing EPC company runs 5–20 projects simultaneously, each at different stages. Without a system, resource allocation, material availability, and cashflow across all projects is impossible to see in one view
- Project-specific procurement: Materials are purchased for specific projects, not a general warehouse. Panels procured for Project A cannot be deployed to Project B without tracking the switch it creates warranty, ownership, and billing confusion
- Milestone billing complexity: EPC contracts typically have 4-5 payment milestones. The trigger for each invoice is a project event. Finance needs to know the moment that event happens
- Equipment serialization: Every solar panel, every inverter, every BESS unit delivered to a project site has a serial number. That serial number is the link to the manufacturer warranty and to the O&M service record that follows for the next 10–25 years
How Odoo Manages Solar EPC Projects
Project Setup and Scope Definition
Each EPC project is created in Odoo with its client, contract value, planned start and end dates, and project manager. The project scope defines the phases Survey & Design, Procurement, Civil & Structural, Electrical Installation, Commissioning, Handover as project tasks or stages. Budgeted costs per phase are entered at project creation, establishing the baseline against which actual costs are measured throughout.
Bill of Quantities and Material Planning
The system capacity (kWp or kWh) drives the Bill of Quantities (BoQ). For a 100kWp commercial rooftop system, Odoo's manufacturing or project module generates the material requirement:
- 250 × 400Wp monocrystalline panels
- 2 × 50kW string inverters
- Mounting structure (aluminium rails, clamps, roof anchors)
- DC cables, AC cables, conduit, protection equipment
- BESS units (if hybrid or off-grid)
- Monitoring system, metering equipment, LT panel upgrades
Each item is a product in Odoo inventory. The BoQ becomes a purchase requisition or stock reservation order materials are either procured specifically for this project (project-specific stock reservation) or drawn from general warehouse stock with the project code assigned at the point of dispatch.
Project-Specific Stock Reservation
When panels and inverters are purchased for Project A, they are received into a dedicated project location in Odoo not the general warehouse. This ensures that 250 panels invoiced to Project A's budget are physically and digitally ring-fenced from other projects. If a shortage occurs (one panel damaged in transit), the system immediately shows the shortfall against the project's requirement no surprise on installation day.
Equipment Serial Tracking on Delivery
When panels, inverters, and BESS units arrive on site, the delivery is received in Odoo with serial numbers scanned or entered. Each serial number is now linked to:
- The specific project it belongs to
- The purchase order it came from (and therefore the supplier)
- The delivery date (which starts the supplier warranty clock)
- The physical installation location (string number, roof zone, or racking position)
This serial-to-project linkage is what makes O&M possible later. When a panel fails in Year 3, the O&M team opens Odoo, searches the serial number, and sees exactly which project it belongs to, which string it's on, when it was installed, and whether it's still under supplier warranty.
Subcontractor Management
Civil works, electrical wiring, and rooftop installation are frequently subcontracted. Odoo manages subcontractor purchase orders with scope of work references, mobilization amounts, and payment terms linked to project milestones. Subcontractor invoices are matched against the project budget so the full cost picture (materials + direct labour + subcontracting) is visible per project at any time.
Milestone-Based Billing
EPC contracts commonly structure payments around project events:
| Milestone | Typical % | Trigger |
|---|---|---|
| Mobilization advance | 20–30% | Contract signing / survey completion |
| Equipment delivery | 30–40% | Panels and inverters delivered to site |
| Installation complete | 20–30% | Mechanical and electrical installation done |
| Commissioning and handover | 10% | System live, net metering applied, client sign-off |
Odoo links each invoice to its project milestone. When the project manager marks a milestone as complete, finance receives a notification to raise the corresponding invoice. There is no delay, no email chain asking can we invoice the delivery milestone? the system triggers it.
Cost visibility example: A 500kWp industrial project has a contract value of PKR 85 million. At week 6, the project manager can see in Odoo: materials consumed PKR 52M (61%), subcontractor costs PKR 8M (9%), direct labour PKR 3M (4%), total cost to date PKR 63M against 70% project completion. Margin is tracking at 17% vs the 20% budgeted a 3% variance visible six weeks before completion, not at the final invoice.
Commissioning and Handover Documentation
At commissioning, Odoo generates the complete project handover package from the data already in the system:
- Equipment list with serial numbers and warranty details
- As-built material schedule (what was actually installed vs what was specified)
- Test and commissioning records
- O&M schedule for first-year preventive maintenance
- Net metering application documents (system capacity, equipment specs)
The client receives a professional handover package generated directly from project data not manually assembled from scattered emails and spreadsheets.
Managing Multiple Concurrent Projects
The Odoo project dashboard shows all active projects simultaneously current phase, percentage complete, budget consumed, next milestone date, and any blocked tasks. A project director managing 15 concurrent projects can see which ones are on track, which are at risk, and which are waiting for materials in one screen, without opening 15 separate files.
Implementation timeline: A solar EPC Odoo deployment covering project management, procurement, stock reservation, serial tracking, milestone billing, and subcontractor management typically takes 10 to 14 weeks.
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Frequently Asked Questions
Can Odoo track which specific panel is installed in which string on which project?
Yes. At the time of installation, panels can be assigned to string-level locations within the project's site structure in Odoo. Each serial number is mapped to its physical position enabling fault isolation when a string underperforms. This level of detail is particularly valuable for O&M teams and for warranty claims against panel manufacturers.
How does Odoo handle project variations scope changes after contract signing?
Variation orders are managed as additional project tasks or budget amendments in Odoo. Each variation is linked to the original project, captures the additional scope and cost, and generates a variation invoice. The project budget automatically reflects the approved variation so profitability tracking remains accurate even as scope evolves.
Can Odoo manage multiple projects sharing equipment from a central warehouse?
Yes. Odoo supports both project-specific stock reservations and shared warehouse dispatch. If your company maintains a buffer stock of panels for immediate deployment, Odoo tracks the allocation per project and adjusts the shared stock levels accordingly. The project code on every stock movement maintains cost and traceability integrity.
Does Odoo handle retention amounts in EPC contracts?
Yes. Retention (typically 5–10% held by the client until the defects liability period expires) is configured in Odoo's payment terms. The retention amount is recorded on the invoice, tracked as a receivable, and released as a separate payment when the defects period ends without requiring manual calculation or separate tracking.