Overview
ISO/CIE TR 3092:2023 is a technical report that accompanies ISO/CIE 20086 and provides explanation, justification and practical guidance for assessing the energy performance of lighting in buildings. Rather than adding normative content to the core standard, this report clarifies intent, scope and limitations, explains the calculation methodology for lighting energy, and gives worked examples (including an annex example for a retail design). It is intended to support correct national implementation and to improve understanding of the lighting energy evaluation methods used to produce the Lighting Energy Numeric Indicator (LENI).
Key topics and technical content
The report expands on ISO/CIE 20086 by detailing:
- Three energy-assessment methods
- Method 1 - Comprehensive calculation: stepwise energy calculation using specified time steps, inputs and operating conditions.
- Method 2 - Quick calculation: simplified/fast approach for screening or early design stages.
- Method 3 - Direct metering: using measured energy consumption for lighting where separate metering is available.
- Inputs and data requirements, including lighting system data, product data, system design parameters and operating conditions.
- Calculation procedures such as applicable time steps, operating-condition computations and annual energy estimation.
- Expenditure factors and how they complement LENI to make system energy flows more transparent.
- Quality control and compliance checks for each method to ensure reliable results.
- Terminology, symbols and abbreviations, aligned with ISO/CIE 20086 and CIE S 017 (International Lighting Vocabulary).
- Worked calculation example(s) that illustrate application of integrated lighting control options and daylight considerations.
Practical applications
ISO/CIE TR 3092:2023 is practical for:
- Designing energy-efficient daylight and electric lighting schemes.
- Estimating annual lighting energy loads for building energy models and HVAC load interactions.
- Producing LENI values for building compliance, benchmarking and code reporting.
- Evaluating the impact of lighting controls, daylighting and system design choices on energy use.
- Implementing metering strategies to monitor lighting energy performance.
Who should use this standard
- Lighting designers and specifiers
- Energy assessors and building performance modelers
- Facility managers and maintenance engineers
- Regulators and code writers adopting ISO/CIE 20086 in national contexts
- Manufacturers and product certifiers seeking to understand energy-accounting implications
Related standards
- ISO/CIE 20086:2019 - Light and lighting - Energy performance of lighting in buildings (normative companion)
- CIE S 017 - International Lighting Vocabulary
This report is a practical explanatory resource - use it to interpret ISO/CIE 20086 correctly, apply the appropriate calculation method, and ensure robust, compliant lighting energy assessments.