Solar Bill of Materials and Procurement Support

The bill of materials (BOM) is the bridge between engineering design and physical installation. Getting the BOM right means installations happen on time with the right materials on site. Getting it wrong means truck rolls with missing components, project delays, and frustrated crews. RIH Engineering delivers BOM preparation and procurement support as an outsourced back-office service for US solar EPCs, installers, and developers.

What you get

• Detailed BOM preparation per project with complete component lists (modules, inverters, racking, wiring, disconnects, protective equipment, monitoring, balance-of-system)
• Material takeoffs from plan sets with quantity verification
• Equipment specification packages for procurement teams
• Vendor RFQ (Request for Quote) preparation for competitive sourcing
• Purchase order preparation and coordination with your procurement team
• Material tracking and receiving documentation
• Return coordination for over-ordered or defective materials
• Vendor scorecard tracking for on-time delivery and quality
• BOM cost analysis against project budget

What we handle for you

BOM work is precise but repetitive. Every project requires counting modules, calculating wire runs, specifying racking components down to the correct clamp count, and cross-referencing against equipment cut sheets. Skilled procurement staff can do this but their time is better spent on vendor negotiations and inventory optimization, not manual BOM extraction.

We take BOM preparation off your plate. You send us the plan set. We come back with a complete BOM including quantities, part numbers, vendor recommendations, and any custom BOM format your procurement team uses. Your procurement team focuses on strategic sourcing, not manual counting.

The cost of doing this in-house

BOM errors are one of the top causes of installation delays. Missing components, wrong quantities, or incorrect specifications force truck rolls, delay installations, and destroy crew productivity. A single delayed install costs 4 to 8 crew hours at $60 to $100 per hour, plus indirect costs of customer delays and reputation damage.

Multiplied across a growing pipeline, BOM errors quietly cost solar companies tens of thousands of dollars per year. Companies with dedicated BOM teams have materially lower error rates than companies where BOM is a shared responsibility across engineers and procurement staff.

Why RIH Engineering is safe to try

Send us one plan set. We deliver a complete BOM in 24 to 72 hours. You compare against your procurement standards. If the BOM doesn't match your quality bar, we adjust to your templates until it does. No long-term commitment.

Our BOM team works with all major solar equipment manufacturers (Enphase, SolarEdge, Tesla, LG, Q Cells, REC, SunPower, and others) and maintains current part number and pricing databases. We adapt to your BOM format rather than forcing you into ours.

Our process

1. You send us the plan set and any specific equipment or vendor preferences
2. Our BOM specialist extracts component counts from plan set drawings
3. Wire runs calculated with 10 to 15 percent slack for terminations and losses
4. Racking components counted including clamps, mid-clamps, end-clamps, and rails
5. BOS components added (disconnects, combiner boxes, monitoring, grounding, labels)
6. Complete BOM compiled with part numbers, quantities, and vendor recommendations
7. Vendor RFQs prepared where competitive sourcing is required
8. BOM formatted per your procurement template and delivered for review

Tools and standards

Our BOM team works in Excel, Google Sheets, and procurement platforms including NetSuite, SAP, QuickBooks, and industry-specific tools. We maintain current part number databases across major solar equipment manufacturers and stay current on new product releases and discontinuations.

Client-preferred tools: Our team can be trained to use the tool preferred by the client. If your workflow depends on a specific platform, template, or software, we adapt to it rather than force you into ours.