Benchmarking energy means measuring the energy consumed by a building, using a standard set of tools like the Portfolio Manager, and comparing these measurements against a relevant set of energy consumption data using a program like Energy Star. Energy benchmarking in CA is currently mandated for certain non-residential buildings of size greater than 10,000 sq. ft. which are sold, leased or refinanced.
The legislation for energy benchmarking for CA buildings calls for a mandatory disclosure of energy benchmarking data by buildings within a certain timeframe. This is primarily enforced by AB 1103 – the Commercial Building Benchmarking Law that was signed by the Governor in 2009 and it currently applies to non-residential buildings. This bill is now regulated by the CEC and it mandates that by the end of 2011, CA based Utilities like PG&E are able to provide energy consumption data per request from their customers as a first phase of implementation. The second phase for implementing the same law requires that by 2012, non-residential building owners will have to disclose benchmarking data for the refinancing, sale or lease to the market for an entire building.
The timeframes for implementing benchmarking criteria (as defined in AB 1103) are separately established by AB 531 which provides for the CEC to establish the schedule to implement AB 1103 through a CA non-residential building energy use disclosure program.
Accordingly the requirement for implementing AB 1103 is that by 2012 buildings with 50,000 square feet area should disclose their energy benchmarking data; that by Jan 2013 buildings with areas between 10,000 and 50,000 square feet should disclose their benchmark data, and that finally by July 2013 buildings with areas between 5,000 to 10,000 square feet should disclose their energy benchmark data. AB 1103 also mandates that buildings that are eligible to receive Energy Star scores from 1 – 100 must also disclose their final scores to the market.
The energy benchmarking process is itself carried out by following certain steps as outlined by the Portfolio Manager. The energy performance rating resulting from this process utilizes certain building variables affecting energy consumption like Building Size, Space Type, Weather, Hours of Operation, Occupancy and Plug Load. Once a building has its energy benchmarking data, it also sets itself up for periodic energy audits to measure changes in energy consumption patterns over periods of time.
Utilities like PG&E now provide Automated Benchmarking Service (ABS) for their customers which create Portfolio Manager Accounts for users and allow them to view energy consumption data and benchmarking results online. Similarly the City of San Francisco is also active in disseminating information about energy benchmarking strategies that it plans to carry out through webinars in collaboration with Utilities like PG&E, as well as by establishing detailed ordinances that describe the practicalities of dealing with benchmarking data from commercial buildings in San Francisco. The city’s goal is to reduce energy consumption by 50% over the next 20 years by identifying potential savings, engaging tenants, and leading by example in public facilities.