Have you ever seen a light bulb with "energy efficient" mark on it and wondered what that means? Today, we are going to talk about efficiency and its relationship to energy.
Efficiency is the ratio of the amount of useful energy produced (energy output) to the amount of energy used (energy input). In the light bulb example, the electrical energy provided is the energy input, and the light that the bulb produced is the energy output. Efficiency can be calculated by using the following equation:
efficiency = (E out / E in) x 100%
Some old light bulbs usually have low energy efficiency as large part of its energy input turns into thermal energy/heat instead of light. The advanced light bulbs we use today works more efficient because it turns more energy into light and so save more energy. Majority of wasted energy through energy transformation turn into thermal energy, but electric heater can turn electrical energy into radiant energy rather than thermal energy.
This topic is very interesting because if we compare vehicles and bicycles, we will found that bicycle is the most efficient self-powered vehicle because most of the output kinetic energy form our leg turns into the kinetic energy of the bicycle. Thus, we should ride more bicycles instead of driving cars in order to save our energy.
Some questions I have for this topic include what are the factors that impact energy efficiency? Would conductors save more energy than less conductive things? How does the design of energy efficient light bulbs enhance energy efficiency?
