Samuel Chiltern answered
Fundamentally, there is no difference between sunlight and artificial light, because both are just made up of photon particles.
However, the quality and quantity of sunlight is much better suited to growing plants, for example.
The Differences Between Natural Light and Artificial Light
Naturally, the sun produces far more light than anything on earth, so the intensity and abundance of sunlight should be considered the main thing which differentiates these two types of light.
The quality of sunlight is the other key defining factor. Sunlight contains much more light at both the red and blue ends of the light spectrum, although the exact proportions depends upon the time of year.
When we talk about the quality of light, we use a term called colour temperature, though this should not be confused with heat! Using black as a base (because black is the absence of colour), the colour of light is described using the standard unit of absolute temperature, Kelvin (K).
A matchstick flame has a colour temperature of 1,700K, whereas sunlight, as it sits above the atmosphere, measures 5,900K. It might seem counter-intuitive, but the higher the colour temperature, the more blue the colour - so a clear blue sky could be considered within the range of 15,000K and above.
Incandescent lights (which produce light by heating a filament) produce light between 2,700K and 3,000K, with compact fluorescent (energy-saving) bulbs also producing light at 3,000K.
When farmers use artificial light to grow crops, they will generally use lamps that produce a colour temperature of 6,000K to stimulate plant growth, and will then switch to lights that produce more red light when the time comes to encourage fruiting plants to produce their crops. This mimics the natural variation of sunlight quality as the seasons change.
However, the quality and quantity of sunlight is much better suited to growing plants, for example.
The Differences Between Natural Light and Artificial Light
Naturally, the sun produces far more light than anything on earth, so the intensity and abundance of sunlight should be considered the main thing which differentiates these two types of light.
The quality of sunlight is the other key defining factor. Sunlight contains much more light at both the red and blue ends of the light spectrum, although the exact proportions depends upon the time of year.
When we talk about the quality of light, we use a term called colour temperature, though this should not be confused with heat! Using black as a base (because black is the absence of colour), the colour of light is described using the standard unit of absolute temperature, Kelvin (K).
A matchstick flame has a colour temperature of 1,700K, whereas sunlight, as it sits above the atmosphere, measures 5,900K. It might seem counter-intuitive, but the higher the colour temperature, the more blue the colour - so a clear blue sky could be considered within the range of 15,000K and above.
Incandescent lights (which produce light by heating a filament) produce light between 2,700K and 3,000K, with compact fluorescent (energy-saving) bulbs also producing light at 3,000K.
When farmers use artificial light to grow crops, they will generally use lamps that produce a colour temperature of 6,000K to stimulate plant growth, and will then switch to lights that produce more red light when the time comes to encourage fruiting plants to produce their crops. This mimics the natural variation of sunlight quality as the seasons change.
