442 Energy Project Financing: Resources and Strategies for Success
8.5.1 Approach 1: No IEQ M&V
Table 2 lists several energy conservation measures (e.g., chiller
upgrades) that are either unlikely to affect IEQ or that are likely to
have only a beneficial influence on IEQ. In general, no IEQ M&V will
be necessary when the energy conservation measures are judged highly
unlikely to result in a significant adverse IEQ impact. However, IEQ
M&V may still be performed if the M&V goal is quantify an antici-to
pated improvement in IEQ.
8.5.2 Approach 2: IEQ M&V Based on Modeling
IEQ modeling is usually the only method available to predict the
magnitude of changes in IEQ associated with implementation of energy
conservation measures during new construction. Additionally, modeling
may be appropriate to estimate changes in indoor pollutant concentra-
tions associated with changes in ventilation rates or when measurement
methods are too expensive or not available.
Very simple mass balance models for single zones with well-mixed
air can provide a useful estimate of the change in indoor pollutant
concentrations that are expected when ventilation rates or indoor pol-
lutant emission rates are modified. Many scientific papers describe such
models which can be implemented using spreadsheet software (e.g.,
Persily and Dols 1990, Nazaroff et al. 1993, Fisk and deAlmeida. 1998).
Several much more complex multi-zone models are available (National
Laboratories 1997, Chapter 3). Many of the complex models require
extensive model inputs and considerable IEQ modeling expertise.
Lighting simulation tools such as the Radiance program (Ward and
Rubinstien 1998) can model the resultant luminance distribution from
most lighting and daylighting systems; however, only a few lighting
quality parameters, such as glare, are computed by these tools. Exten-
sive model inputs and considerable modeling expertise are required.
8.5.3 Approach 3: Short-Term Measurements of
Selected IEQ Parameters
Short term measurements of IEQ parameters (e.g., measurements
for a month or less) may be used for IEQ parameters that do not vary
significantly with season or with the mode of building operation. Ex-
amples of such parameters are light levels in core zone of building and
minimum outside air flow rates in constant volume HVAC systems.
Short term measurements may also be appropriate when the outcome
of interest is an IEQ parameter for a defined set of climatic and building