Energy and Atmosphere
What the category covers
EA is the largest point category. Prerequisites in v4 BD+C: Fundamental Commissioning and Verification, Minimum Energy Performance, Building-Level Energy Metering, and Fundamental Refrigerant Management. Credits include Optimize Energy Performance, Enhanced Commissioning, Advanced Energy Metering, Demand Response, Renewable Energy Production, Enhanced Refrigerant Management, and Green Power and Carbon Offsets.
Concepts to know
- Minimum Energy Performance is measured against an ASHRAE 90.1 baseline (90.1-2010 in v4; later editions in newer versions). Optimize Energy Performance awards points on a sliding scale of percent improvement in energy cost.
- Whole-building simulation compares proposed vs. baseline with identical schedules, loads, and unmet load hours (keep them ≤ 300 in both models).
- Commissioning: the Cx authority must be independent of design and construction; enhanced Cx adds envelope review, OPR/BOPr, and monitoring-based activities.
- Metering: building-level is the prerequisite; advanced metering means hourly or finer data, remotely collected.
- Refrigerants: no CFC-based refrigerants in new systems; enhanced management adds zero ozone depletion and a low-GWP ceiling.
Traps
- Plug loads and process loads must be modeled consistently - hiding loads in the proposed model invalidates the savings claim.
- On-site renewable energy and green power are separate credits; purchased off-site RECs do not reduce the modeled energy cost in the Optimize credit.
- The Cx agent cannot be the contractor or the design engineer.
Rule of thumb
In v4 NC, each few percent of improvement over 90.1 is worth roughly a point, so a project near 20% savings is mid-scale, not heroic. Never quote a point value without checking the version's table.