An open solar power purchase agreement (PPA) invoice can mean the customer has not paid, or that a receipt has not yet been allocated. Distinguishing those cases helps accounts staff focus on the balances that need action and avoid chasing a customer who has already paid.
1. Start with issued invoices and receipt evidence
PPA providers have billing and collection responsibilities. This workflow begins after invoice issue and uses each contract’s agreed payment due date.
Make status actionable
Separate not yet due, overdue, disputed and received-but-unmatched items. Give each unresolved item an owner instead of placing every case in one overdue list.
Keep a common reference
Connect the customer, contract, site, invoice number and receipt evidence. A reviewer should be able to trace a status back to its supporting document.
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2. Resolve partial and combined payments
One transfer may cover part of an invoice or several invoices. Allocation needs evidence and review; a similar amount alone is not enough.
Record the paid portion
Illustrative example: a 100,000-baht invoice receives 60,000 baht. After verification, track the remaining 40,000 baht while retaining the original receipt and invoice history.
Hold uncertain allocations
For combined payments or deductions, ask accounts to confirm the allocation and supporting documents before marking invoices as settled. Keep the unresolved amount visible.
3. Measure the cost of tracing records
Use one collection cycle to compare the existing process with connected invoice and receipt records. Look for specific reductions in repeated administrative work.
Track unresolved items
Measure the count and age of unmatched receipts, time spent finding documents and repeated enquiries. Review the causes of the oldest unresolved items.
Define the system boundary
PPA Billing supports invoice and payment tracking. Bank feeds, accounting connections and approval rules require assessment against the actual workflow rather than an assumption of automatic matching.
Frequently asked questions
Does money arriving in the bank close an invoice?
First confirm the payer, reference and allocation. This is especially important for partial receipts and transfers covering several invoices.
Which records should be reviewed first?
Start with unmatched receipts and overdue invoices that already have payment evidence. Correct their status before continuing customer follow-up.
Explore Solar PPA invoice and payment tracking
See the DigitechX PPA Billing workflow. Bring a partial or unmatched payment example to discuss how it should work with your existing accounts process.
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References
Information and sources reviewed: 9 October 2026