Materials and Energy: Energy Efficiency

Understanding energy efficiency: This is the measure of how well a device can convert energy input into useful output. The more useful energy a device produces compared to the amount it receives, the more energy efficient it is.
Calculating energy efficiency: This is usually expressed as a percentage and can be calculated using the formula: (useful energy output / total energy input) x 100%.
Role of energy efficiency in sustainability: By utilising devices that are more energy efficient, we can reduce the amount of energy we use, thereby conserving limited energy resources and reducing carbon emissions.
Energy wastage: Not all energy input is converted into useful output. In many devices, a significant proportion of energy is wasted, often as heat. For example, in traditional incandescent light bulbs, about 90% of the energy consumed is given off as heat, with only 10% used to produce light.
Improving energy efficiency: Technological advancements allow for the production of more energy efficient devices. For example, using spacecraft technology, we see the development of LED lights, which are much more efficient than traditional light bulbs.
Insulation: This is an important method of improving energy efficiency in buildings. Insulated walls, roofs and double-glazing windows reduce heat loss, thereby reducing the amount of energy needed for heating.
Renewables and energy efficiency: The use of renewable energy sources, such as solar or wind power, is another form of improving energy efficiency and sustainability. These technologies harness natural energy sources and convert them into useful energy with little or no pollution.
Domestic energy efficiency: Energy-saving lightbulbs, efficient appliances and improved insulation can all significantly reduce the amount of energy a household uses.
Waste energy: Energy that isn’t used effectively is known as ‘waste energy’. The reduction of this kind of energy would lead to higher energy efficiency.
Towards a sustainable future: Advancements in technology and an increased understanding of the importance of conservation is allowing societies to move towards a sustainable future, where wastage is minimized and we make the most of the energy resources that are available.