2.1: Energy Sub-Metering

(65 points)

GREEN GLOBES #2.1.1 Is electricity separately metered for the interior space?

• Yes (10 points)
• No (0 points)

Assessment Guidance

An Energy Metering and Reporting Plan should contain measurement, verification, metering, and reporting energy use information for the building systems that are within a tenant’s domain of control. Only building systems that directly affect the project space are required to be addressed verified as part of this assessment. 

• Primary energy systems 
  • Chilled water generation; 
  • Heating water or steam generation; 
  • Furnaces; 
  • Boilers; 
• Major electrical direct end uses 
  • Lighting; 
  • Plug loads; 
  • Electric HVAC components (such as chillers, cooling towers, AHU fans, and major pumps); 
  • Specialty or process electrical equipment; 
  • Secondary electric HVAC equipment as appropriate(e.g. heat pumps, fan coils, fan powered boxes); 
• Status monitoring and verification of critical HVAC controls (e.g. scheduling, economizer operation, temperature/pressure resets);
• Potable hot water systems; 
• On-site renewable energy power generation; 
• Other sub-metered energy sources (propane, steam, natural gas, wood for example).

In setting up the Energy Metering and Reporting Plan, the anticipated energy demand and consumption values for each of the above mentioned end-uses should be estimated or extracted from the building energy model (if available). From there, the Building Automation System (BAS) or other automated building control system should be set-up to continually track and report energy usage broken down by major end-use, where possible.

Where sub-metering is not practical or possible, or where alternative logging or metering would provide better results (such as short-term logging or BAS polling), the measurement, analysis, and reporting of the alternative monitoring should be documented in the Energy Metering and Reporting Plan.

GREEN GLOBES #2.1.2 Is there sub-metering installed for the following:

Tooltip

Sub-metering: subdivision of the utility metering of a building that records the proportionate energy use of specific building systems and appliances.

Assessment Guidance

The Green Globes Assessor will review the mechanical and electrical plans, which should clearly show what major end-uses will be sub-metered. Additionally, designing separate circuits for different end uses—lighting, hot water, heating/cooling, plug loads, for example—will make it easier to resolve actual end uses.

Specialty or process electrical equipment should not be confused or combined with the plug loads end-use. Specialty/process electrical equipment refers to hardwired equipment, like MRI machines in hospitals, or vertical transportation in commercial buildings. Plug loads should only consist of items that are not electrically hard wired but must be physically plugged in to an electrical outlet.

GREEN GLOBES #2.1.2.1 : Lighting?

• Yes (10 points)
• No (0 points)

GREEN GLOBES #2.1.2.2 : Plug loads?

• Yes (10 points)
• No (0 points)

GREEN GLOBES #2.1.2.3 Large specialized equipment (e.g. servers, medical equipment, MRI units, etc.) that are likely to produce more than 10% of annual energy use?

• Yes (10 points)
• No (0 points)
• N/A

Tooltip

Mark “N/A” for a facility less than 20,000 ft2 or where these types of large equipment or systems are not present.

GREEN GLOBES #2.1.2.4 : Other equipment or systems that impact energy?

• Yes (10 points)
• No (0 points)
• N/A

Tooltip

For example, a chiller plant retro-fitted for waste heat . Mark “N/A” where no systems other than lighting, plug loads, or specialized equipment are in place that can be sub-metered or logged.

GREEN GLOBES #2.1.2.4.1 Describe the sub-metering used for any other equipment or systems that impact energy use.

If none, enter "None."

Tooltip

This criterion is informational only and is not scored. Points for sub-metering additional equipment or systems are awarded under criterion 2.1.2.4

GREEN GLOBES #2.1.3 Is there a monitoring feature that includes continuous or regular updates shared with tenants for different energy end uses, plug loads, and high energy use equipment?

• Yes (10 points)
• No (0 points)

Tooltip

Mark “N/A” if tenants have no influence over the metering or logging of energy use in their space, only if building lessor or owner does not permit or support energy use tracking and apportioning source energy to the tenant space.

Assessment Guidance

Aside from electric sub-metering , data collected from the building automation system (BAS) or other data tracking systems (such as temporary loggers) can be developed to generate time series profiles of actual energy end uses in a space. Use of interval metering or programming the BAS is one way to capture energy use patterns. Such data can be tabulated, charted or further developed to review trends and anomalies. Regularly-reported data is the key to determining possible causes of problems, such as control drift, set point overrides, scheduling errors, and other operational issues. With this information, corrective action can be taken to modify operational parameters (such as set points, ventilation requirements, HVAC resets, schedules or behavior changes to bring energy use back to acceptable ranges.

GREEN GLOBES #2.1.4 Is there a formal written plan, approved and signed by building management, with provisions that the monitored data is analyzed, configured and reported in such a way that tenants can take corrective action to reduce loads based on the reported results?

• Yes (5 points)
• No (0 points)

Tooltip

A relevant, useful plan would address the who, what, when, and how the data is collected, analyzed, reported, reviewed, and the processes for following up on reported information to improve energy efficiency.

Assessment Guidance

A typical plan would include the following kinds of information and details: 

• The type, frequency, and units of the data to be collected. 
• Description of the algorithms or methods used to analyze the data (e.g. equations imbedded in a spreadsheet tool). 
• Persons responsible for collecting and analyzing the data. 
• A flow chart identifying the key tasks in the overall process of data collection, analysis, reporting, review, and follow-up. 
• Sample of mock-up of an actual or typical report. 
• Example of the kinds of summaries and recommendations associated with the report. 
• Example of the kinds of corrective actions or procedures to be followed that could be taken to follow up on recommendations. 
• Goals or target results to be achieved. 
• Cumulative historical results (such as bar charts, pie charts or tables) that graphically display progress toward goals.

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