An LED is a device containing layers of semiconducting materials that will very efficiently convert electrical energy into light energy. It’s light from a chip. And it’s this ability to maximise output (illumination) from minimal input (power consumption) that has really made solid state lighting a star turn, in particular through the green revolution it is now facilitating. Our old incandescent bulbs with their glowing filaments would waste upwards of 80% of their energy as heat, whereas for LEDs this loss is down at around 5-10%. The diodes are also more robust and therefore last longer – at least 30 times longer – as a consequence.
BBC 2nd Feb 2021 read more »