← All revision guidesSEMESTER 4 · DI04009021
6FLASHCARDSEnergy Efficiency and Audit
Energy accounting, demand management and efficiency assessment.
Audit fundamentals
Q1What is an energy baseline?
It is a reference pattern of energy use against which later performance or savings are compared.
Q2Differentiate energy and demand.
Energy is accumulated consumption in kWh; demand is the rate of power use, commonly measured in kW or kVA over an interval.
Q3What is a specific energy consumption indicator?
It is energy used per unit of useful output, such as kWh per tonne of product.
Efficiency measures
Q1Why does power-factor improvement reduce system losses?
For the same active power it reduces current, so conductor and transformer I²R losses decrease.
Q2Why should an oversized motor be reviewed?
A lightly loaded motor may operate with lower efficiency and power factor than a correctly sized motor.
Q3How are annual monetary savings estimated?
Multiply verified annual energy and demand reductions by the applicable tariff components, then subtract recurring costs.