ENERGY AUDITS & RETRO-COMMISSIONING OF BASE BUILDING SYSTEMS

Local Law 87

Introduction

Building audits are used to identify all potential energy-saving retro-commissioning (operational) and retrofit (capital) measures. Once every 10 years, the legislation requires large buildings to perform both an energy audit and retro-commissioning study of central (base building) systems. The energy audit and retro-commissioning reports are combined into an Energy Efficiency report. Individual tenant spaces are exempt from both processes.

Requirements

The energy audits and retro-commissioning studies only apply to buildings’ central systems, including the building envelope, HVAC systems, conveying systems, domestic hot water systems, and electrical and lighting systems. This includes systems within tenant spaces that are owned and maintained by the owner, such as perimeter heating. It does not include systems that are within tenant spaces that are owned and maintained by the tenant, such as unitary HVAC. Industrial processes (chemical or mechanical procedures involved in manufacturing an item) are also exempt from this legislation.

The energy audit must be an ASHRAE Level II Audit. This process identifies at a minimum:

• All potential energy use-reducing measures
• The associated cost, annual savings, and simple payback for each measure
• The building’s benchmarking output, consistent with the USEPA Portfolio Manager tool
• A breakdown of energy use by system and related predicted savings
• How tenant-space energy use impacts the central system’s energy consumption

Retro-commissioning

Through analysis, corrections and testing, the agent must certify that all systems and operations are running efficiently. These include all valves, sensors, controls, programmed settings and/or operational practices regarding HVAC, lighting, water, and other systems.

Deadline

Energy efficiency reports are due once every ten years. The first reports must be filed by 2013. They are due in a staggered schedule, based on the last digit of the building’s tax block number and the date of occupancy for newer buildings. The Department of Finance will notify each building of the requirements three years prior to the due date, and every year thereafter until the due date. Buildings must report within their due year.

Documentation

The energy audit report must be conducted under the supervision of an energy auditor (a registered design professional). The retro-commissioning study must be completed by a retro-commissioning agent. Both must be completed within four years before the energy efficiency report is filed. Documentation must be kept at every building.

Who needs to comply?

NYC Local Law 87 Full Text (pdf)