P1.2 - AQA GCSE Physics Unit 1 - Overview

P1.2	Energy and efficiency Appliances transfer energy but they rarely transfer all of the energy to the place we want. We need to know the efficiency of appliances so that we can choose between them, including how cost effective they are, and try to improve them. Candidates should use their skills, knowledge and understanding to:
	■ compare the efficiency and cost effectiveness of methods used to reduce 'energy consumption'	The term 'pay-back time' should be understood. Given relevant data, candidates should be able to make judgements about the cost effectiveness of different methods of reducing energy consumption over a set period of time. This is not restricted to a consideration of building insulation but may include: ■ low energy light bulbs and LED lighting ■ replacing old appliances with energy efficient ones ■ ways in which 'waste' energy can be useful, eg heat exchangers.
	■ describe the energy transfers and the main energy wastages that occur with a range of appliances	Common electrical appliances found in the home will be examined. Examples will not be limited to electrical appliances; however, in this case all the information would be given in the question.
	■ interpret and draw a Sankey diagram.	Candidates should be able to use a Sankey diagram to calculate the efficiency of an appliance.

There is only one section to this part of the syllabus:

P1.2.1 - Energy transfers and efficiency

There is also a page suggesting practical experiments that should be carried out during the study of this section.