Light Source Comparison Chart
Sunlight
Pro
full spectrum range,
free access if using out-door or large-windowed growing area
Contra
day length might not be ideal for non-native crops,
increase of UV rays interferes with photosynthesis and damages DNA
Incandescent
Pro
legacy technology with cheap fixtures
Contra
high electricity use (expensive),
inefficient light-to-heat ratio, lack of blue-violet light (Dashur, R.H., & Mehta, R.J.,1935) (less efficient photosynthesis),
more difficult to replace bulbs in some jurisdictions as they are being phased out
Fluorescent
Pro
excellent red range with little-to-no far-red,
cheap bulbs and fixtures,
more energy efficient than incandescent
Contra
mercury content in bulbs (hazardous waste, expensive to dispose of properly)
LED
Pro
variety of light range options available,
very high energy efficiency, resulting in lower electricity bills,
no mercury in bulbs,
long bulb length-of-life (less expensive over the long term, and ideal for fixtures which are difficult to reach to replace bulbs)
Contra
higher initial bulb cost