Electrical Energy Flashcards
What should an electrical appliance do?
It is designed for a purpose and should waste as little energy as possible
What is power?
The rate at which an appliance transfers energy/ energy transferred or supplied per second
How much energy does an appliance with a power rating of 1 transfer every second?
1 watt of power
How many watts are in a kilo watt?
1000 watts
What is a kilo watt hour?
The amount of energy transferred by a one-kilowatt appliance when used for an hour
How can you calculate the cost of the electrical energy supplied?
Number kWh x cost per kWh
What must be considered to compare cost- effectiveness?
Cost of buying the appliance Cost of installing the appliance Running cost Maintenance cost Environmental cost Interest charged on a loan to buy the appliance
What might an environmental cost include?
The removal and disposal of old equipment and environmental taxes
How might a householder reduce their energy bills?
Buying newer more efficient appliances
Install materials designed to reduce energy wastage
Loft insulation costs £600 including installation. It saves £80 a year. How long is the payback time?
7 years and 6 months
What is payback time?
The time it takes for an appliance or installation to pay for itself in terms of energy savings
What can electrical appliances do?
Transfer electrical energy into useful energy at the flick of a switch
