Enhancing Solar PV Performance Testing with ASTM Standards: A Keentel Engineering Perspective

Introduction

As the solar photovoltaic (PV) industry rapidly matures, accurate performance testing becomes critical for validating system efficiency, securing investor confidence, and ensuring long-term returns. At Keentel Engineering, we specialize in applying ASTM standards to solar PV projects—streamlining bankability, risk reduction, and performance verification.

The Shift from PVUSA to ASTM: A Critical Evolution

The legacy PVUSA test method, though innovative, suffered from:

• Non-standardized instruments and calibration,
• Inconsistent data intervals and filtering,
• Seasonal fluctuations impacting capacity readings,
• Unclear reporting practices.

These issues created financial risk and project uncertainty.

Bridging the Gap: ASTM E2848 and E2939 Standards

To resolve these inconsistencies, ASTM introduced:

• ASTM E2848-13 (Reapproved 2023) – Establishes robust methods for PV performance testing and reporting.
• ASTM E2939 – Provides guidance on seasonal adjustment and expected system output.

These standards now serve as the foundation for modern, bankable solar power testing.

H3 Key Features of ASTM E2848 for Solar PV Performance Testing

1. Purpose and Scope

This standard outlines:

• Acceptance testing procedures,
• Capacity calculations under natural sunlight,
• Exclusions: module-level testing, inter-site comparisons, and predictive modeling.

2. Data and Measurement Protocols

ASTM E2848 requires:

• Calibrated pyranometers, thermocouples, and anemometers,
• Defined sampling intervals and averaging methods,
• Accurate reporting of solar irradiance, temperature, and wind speed.

3. Regression Modeling

Utilizes multivariate regression to correlate environmental variables with power output. This adjustment allows fair comparisons across varying conditions.

4. Reporting Requirements

• Independent reproducibility,
• Transparent test setup and metrics,
• Alignment with EPC or PPA contract acceptance criteria.

NREL and ASTM Contributions to Industry Best Practices

The National Renewable Energy Laboratory (NREL) supports ASTM via:

• Solar spectral reference tables (e.g., ASTM G173),
• Calibration protocols (ASTM G138, G167),
• Datasets like the National Solar Radiation Database (NSRDB).

These tools help standardize inputs for accurate PV performance modeling and bankability.

Performance Testing and Project Finance

In today’s solar project lifecycle:

• Performance testing validates system design and construction quality,
• Reduces financial risk for investors and EPCs,
• Influences the price paid at financial close.

Referencing Black & Veatch, performance testing is now embedded in modern contractual frameworks.

Why Keentel Engineering Champions ASTM-Based PV Testing

At Keentel Engineering, our methodology aligns with ASTM at every project phase:

• Design Phase: Use of spectral data and irradiance modeling.
• Construction QA/QC: Field validation against ASTM standards.
• Commissioning and Verification: Post-construction tests via ASTM E2848.

➡️ Utility-Scale Solar Engineering Services.

Conclusion

ASTM E2848 is reshaping how solar PV performance is verified—bringing transparency, consistency, and trust to the process. Keentel Engineering continues to lead the way by delivering ASTM-compliant testing, engineering, and validation solutions for developers, EPCs, and financiers.

➡️ See our Power System Performance Analysis

Frequently Asked Questions (FAQs)

Let’s Talk Solar PV Compliance with Keentel Engineering

Keentel Engineering is your expert partner for:

• ASTM E2848-based PV performance validation
• NREL-compliant irradiance and spectral modeling
• Bankable capacity testing for utility-scale projects
• Third-party QA/QC and acceptance testing