Narrative for Energy Audit Level 1 2 3 Final.docx

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Energy Audit Narrative

Preliminary Energy--Use Analysis {PEA) Before any level of energy analysis has begun, it is valuable to perform a PEA to determine a building's current energy and cost efficiencies relative to other, similar buildings. This is normally done by calculating the energy use and cost per unit area per year, which can indicate the potential value of further levels of analysis. This preliminary analysis generally includes the following steps:

1. Determine the building's gross conditioned floor area and record this on the basic building characteristics form (use the PEA Template in Part 3 and at www.ashrae.org/PCBEA). Classify the primary use of the building. Ensure that the standard definition of gross floor area 1s used, which is:

The sum of the floor areas of all the spaces within the building with no deductions for floor penetrations other than atria. It is measured from the exterior faces of exterior walls or from the centerline of walls separating buildings, but it excludes covered walkways, open roofed-over areas, porches and similar spaces, pipe trenches, exterior terraces or steps, roof overhangs, parking garages, surface parking, and similar features.

2. Assemble copies of utility bills and summarize them for at least a one year period, preferably for a two- or three-year period. Review the monthly bills for opportunities to lower costs by taking advantage of different utility rate classes, considering peak electric demand patterns. Review the monthly patterns for irregularities. Note if a bill is missing or if it is estimated rather than an actual consumption value.

3. Complete the energy performance summary to develop the EUI and the ECI for each fuel or demand type and their combined total using methods outlined in ASHRAE Standard 105 (ASHRAE 2007a).

4. Compare the EUI and ECI with those of buildings having similar characteristics. A common benchmark comparison for peer buildings is the ENERGY STAR Portfolio Manager of the U.S. Environmental Protection Agency (EPA) (2011a). The owner/operator of the subject building may have similar buildings for this comparison. Comparison should also be made with publicly available energy indices of similar buildings. In all cases, care should be taken to ensure that comparison is made with current data, using consistent definitions of building usage and floor area.

5. Derive target energy, demand, and cost indices for a building with the same characteristics as the building being analyzed. A range of methods are available for this work, including

· choosing from any database of similar buildings those buildings with the lowest energy index and choosing an index based on the knowledge of an energy analyst experienced with this type of building.3

6. Compare the energy and cost savings for each fuel type if the building were to reach the target EUI. Using these values, determine whether further engineering analysis is recommended.

Use the PEA Template found in Part 3 and at www.ashrae.org/PCBEA to assist with developing and comparing the ECI and EUI and analyzing monthly energy use.

Level 1—Walk Through Analysis The Level 1 process includes all the work performed for the PEA plus the following steps:

1. Perform a brief walk-through survey of the facility to become familiar with its construction, equipment, operation, and maintenance.

2. Meet with the owner/operator and occupants to learn of special problems or planned improvements (e.g., HVAC equipment replacements, aesthetic upgrades, etc.) of the facility and any operation or maintenance issues. Determine whether any maintenance problems and/or practices affect efficiency.

3. Perform a space function analysis, guided by sheet 1.12 in the PCBEA Sample Forms in Part 3 and at www.ashrae.org/PCBEA. Determine whether efficiency may be affected by functions that differ from the original functional intent of the building.

4. Identify low-cost/no-cost changes to the facility or to O&M procedures and estimate the approximate savings that will result from these changes.

5. Identify potential capital improvements for further study and provide an initial rough estimate of potential costs and savings.

The report for a Level 1 analysis should contain the building characteristics and energy use summary as well as the following items:

· Quantification of any savings potential from changing to a different utility rate structure.

· Discussion of irregularities found in the monthly energy use patterns, with suggestions about their possible causes.

· The Eui’s of similar buildings. Report the source, size, and date of the sample used in this comparison. The names of comparable buildings should be given if known.

· The target EUI and the method used to develop the target index. Where comparison is made to other buildings, state their names or the source of the database. Where the experience of someone other than the report author is used to develop the target, provide the source. Where the target is developed by calculation, show the calculation or quote the name and version of the software used and include both input and output data.

· Total energy and demand costs by fuel type for the latest year and pre ceding two years, if available. Show potential savings in dollars using the energy index format of ASHRAE Standard 105 (ASHRAE 2007a).

· The fraction of current costs that would be saved if the energy index were brought to the target level.

· A summary of any special problems or needs identified during the walk-through survey, including possible revisions to O&M procedures.

· A listing of low-cost/no-cost changes with estimated savings for these improvements.

· The potential capital improvements, with an initial rough estimate of potential costs and savings

Level 2-Enerqy SURVEY and Engineering Analysis The Level 2 analytical procedure is guided by Level 1 analysis and includes the following additional steps:

1. Review mechanical and electrical system design, installed condition, maintenance practices, and operating methods.

2. Describe and analyze the energy-using systems of the building, resulting from on-site observation, measurement, and engineering calculations. Use the PCBEA Sample Forms found in Part 3 and at www.ashrae.org/PCBEA to document the building systems, including the following systems:

· Envelope

· Lighting

· Plug loads

· HVAC

· Domestic hot water

· Laundry

· Food preparation

· Refrigeration

· Conveying

· Pools/saunas/spas

· Process loads

· Others

3. Review existing O&M problems and logs. Review planned building changes or improvements and estimate their costs.

4. Measure key operating parameters and compare them to design levels, for example, operating schedules, heating/cooling water temperatures, the supply air temperature, the space temperature and humidity, ventilation quantities, and task lighting levels. Such measurements may be taken on a spot basis or logged manually or electronically.

Figure 1.

Relationship of ASHRAE Energy Audit Level 1, 2 and 3.

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