CEA Energy Modeling & Simulation Tools 2

Question 1

In EnergyPlus, what does the 'DesignDay' object primarily define?

Accepted Answer

Peak outdoor conditions used for HVAC sizing calculations

Answer

DesignDay objects in EnergyPlus specify extreme weather conditions (temperature, humidity, solar) used to size HVAC equipment at peak load.

Question 2

Which simulation time step setting in EnergyPlus provides the highest temporal resolution for HVAC system interactions?

Accepted Answer

6 minutes

Answer

EnergyPlus supports time steps down to 6 minutes (10 steps per hour), providing the finest resolution for capturing fast-changing HVAC dynamics.

Question 3

When calibrating a building energy model to measured utility data, what statistical metric is recommended by ASHRAE Guideline 14?

Accepted Answer

CV(RMSE) and NMBE

Answer

ASHRAE Guideline 14 requires both CV(RMSE) ≤15% monthly and NMBE ≤5% monthly for calibrated simulation acceptance.

Question 4

In eQUEST, what is the primary purpose of the 'Wizard' interface compared to the 'Detailed Interface'?

Accepted Answer

Wizard guides users through simplified inputs for quick baseline models

Answer

eQUEST's Wizard walks users through a streamlined question-based setup to rapidly create a baseline building model before refinement in the Detailed Interface.

Question 5

What does the term 'thermal mass' represent in building energy simulation?

Accepted Answer

The capacity of materials to store and release heat over time

Answer

Thermal mass refers to a material's ability to absorb, store, and slowly release heat, which can shift peak loads and reduce temperature swings.

(CEA) Certified Energy Analyst Practice Test

(CEA) Certified Energy Analyst Practice Test

CEA Energy Modeling & Simulation Tools 2