Northern Arizona University
OP-7: Building Energy Consumption

Institution has reduced its total building energy consumption per gross square foot of building space compared to a 2005 baseline. 

To aggregate energy consumption data from multiple sources, figures should be converted into MMBtu (one million British thermal units – a standard measure of energy) using the following equivalents: 

     1 kWh = 0.003412 MMBtu

     1 MWh = 3.412 MMBtu

     1 therm = 0.1 MMBtu

     1 kBtu = 0.001 MMBtu

     1 ton-hour = 0.012 MMBtu

     1 MJ = 0.000948 MMBtu

This credit applies to all institutions.

Institutions earn the maximum of 8 points available by reducing building energy consumption per gross square foot of building space by 50 percent.  Partial points are awarded based on the reduction achieved.  For example, an institution that reduced energy consumption per gross square foot of building space by 25 percent would earn 4 points (half of the points available for this credit). 

STARS awards only positive points; points will not be deducted if building energy consumption per gross square foot of building space increased rather than decreased during the time period.

 Points earned are calculated according to the formula below.  Please note that users do not have to calculate the number of points earned themselves; points earned will be calculated automatically when the data listed under Section 5: Reporting Fields is entered in the online reporting tool.  

Points Earned = 16 × { [ (A/B) - (C/D) ] / (A/B) }

A = Building energy consumption in the 2005 baseline year

B = Gross square foot of building space in the 2005 baseline year

C= Building energy consumption in the performance year (most recent year for which data are available

D= Gross square foot of building space in the performance year (most recent year for which data are available)

Timeframe

Performance Period

Report the most recent annual energy consumption data available.  Institutions may choose the annual start and end dates that work best with the data they have (e.g. fiscal or calendar year), as long as data are reported from a consecutive 12-month period.  Report building space from the same time period as that from which energy consumption data are drawn.    

Baseline Year

Report data from the 2005 baseline year.  Institutions may choose the start and end dates that work best with the data they have (e.g. fiscal or calendar year), as long as data are reported from a consecutive 12-month period that includes at least one month in 2005.  Report building space from the same period as that from which energy consumption data are drawn.   

If an institution does not have 2005 data, it may either:

a)      Estimate 2005 data using a trend line based on at least three years worth of data,

or

b)     Estimate conservatively (i.e. estimate that performance has not changed between the baseline and performance year).  Following this approach, an institution would not be able to claim points during its first STARS submission, but would be able to use its previously estimated baseline for subsequent submissions. 

Some of the 2005 baseline figures are based on multiple components.  If an institution has data for some, but not all, of the components of the baseline figure, it may follow either of the approaches above to estimate the missing data and then combine it with the available data. 

Sampling and Data Standards

Include all building energy consumption.  Reporting on a sample or subset of buildings is not allowed for this credit.