Building Energy Efficiency and Sustainability Flashcards

Which ASHRAE Guideline covers measuring energy, demand, and water savings, including statistical criteria for calibrating models?

Answer: Guideline 14

Guideline 14 sets M&V methods and calibration criteria such as CV(RMSE) and NMBE limits.

Under ASHRAE 90.1, total skylight area is prescriptively limited to roughly what percentage of gross roof area?

Answer: 3%

90.1 prescriptively caps skylight area at about 3% of gross roof area, with some daylighting provisions allowing up to 6%.

An air-side economizer with differential dry-bulb high-limit control switches back to minimum outdoor air when:

Answer: The outdoor air temperature is higher than the return air temperature

Differential dry-bulb control uses outdoor air only while it is cooler than the return air.

In the 90.1 Appendix G baseline, how is building orientation normally handled?

Answer: The baseline is simulated at four orientations and the results are averaged

Appendix G averages the baseline results across the actual orientation and rotations of 90°, 180°, and 270°.

Which ASHRAE standard specifies thermal environmental conditions for human occupancy, using metrics such as PMV and PPD?

Answer: Standard 55

Standard 55 defines thermal comfort zones and generally targets PMV between -0.5 and +0.5.

What is the energy-saving purpose of a supply duct static pressure reset in a VAV system?

Answer: It lowers the duct pressure setpoint as long as no zone damper needs more air, which reduces fan energy

Resetting static pressure based on zone damper demand lets the VFD slow the fan and save energy.

For buildings, embodied carbon refers mainly to:

Answer: Greenhouse gas emissions from making, transporting, installing, and disposing of building materials

Embodied carbon covers life-cycle emissions from materials and construction, which are separate from operational carbon.