Final answer:
A Kill-A-Watt meter is used a. to audit electrical usage by measuring the power and accumulated energy consumption of electrical appliances. It helps estimate operating costs and make informed decisions on energy savings by evaluating the efficiency of appliances and deciding when to opt for more efficient alternatives.
Step-by-step explanation:
A Kill-A-Watt meter is useful for auditing electrical usage plug-by-plug and room-by-room. It allows individuals to measure the instantaneous power consumption in Watts and accumulated energy in kilowatt-hours (kWh) of their electrical appliances. This knowledge is valuable for estimating the cost of operating electrical appliances by considering their power consumption rate, how long they're on, and the cost per kilowatt-hour charged by the electric utility.
For example, a toaster may have a higher power rating than a digital clock because it needs more electrical energy to generate heat to toast the bread, whereas a digital clock requires minimal power to operate its display. The power rating of an appliance is crucial for calculating the energy consumed over time. For instance, if the household voltage is 120 V and the operating current is known, the power can be calculated using the equation P = IV. Coupled with the energy cost from the utility, you can assess the efficiency of appliances and make informed decisions about energy consumption and potential savings.
Additionally, the Kill-A-Watt can facilitate decisions about replacing inefficient appliances with ones that have greater efficiencies, such as replacing incandescent light bulbs with compact fluorescent bulbs that require less power to produce the same amount of light.