Which Verification Scope Fits Your Company?
The right supply chain audit scope depends on your company structure, number of sites, and energy setup. Answer two quick questions to determine whether ISRS 4400 or ISAE 3000 fits your green energy certificate verification.
Question 1 of 2
At which level is 100% green electricity sourced?
This determines whether the ZF GE Recommendation or ZF GE Minimum Requirement applies.
All Verification Options at a Glance
| Option | When It Applies | Typical Effort | Timeline |
|---|---|---|---|
| ZF Recommendation (ISRS 4400) | Only for ZF, straightforward setup | ~2 days | Depends on availability |
| Mass Balance (ISAE 3000) | ZF is one of many customers | ~4 days | Depends on availability |
| Dedicated Meter | Separate meter for ZF production | Individual | Individual |
| ISAE 3000 | Also for other customers, universal standard | ~5 days | Depends on availability |
| International Group | Sites in multiple countries | from ~5 days | 6-12 weeks |
Verification cost is borne by the supplier. Effort in auditor days at the current daily rate. Based on current ZF requirements, a positive result is typically valid for approximately 4 to 5 years (subject to change). Exact quote after free consultation.