LED Lighting Costs
LED Lighting Costs
When
considering a new technology, cost is naturally the main topic
of interest. Not only should one consider up-front costs, but
also the accumulative operational costs associated with
powering a lighting system. It is very important for business
owners to understand that investing in LED lighting does not
result in immediate savings, but does promote significant
savings over time. A specific metal halide bulb, commonly used
in gas station canopy lighting, dissipates 400 watts of total
power. A custom LED product designed to substitute this metal
halide, dissipates an amazing 60 watts of total power. Over an
extended period, it is obvious how the 60 watt LED product will
result in dramatic energy savings.
Metal Halide Operation
Metal halides
contain a mixture of gasses within the bulb. As the device
operates, the internal temperature and pressure begins to
increase. Unlike metal halides, LED lights do not feature a
gas, operating under extreme pressures, at very high
temperatures. Instead, the LED lights contain a solid state
lighting element, eliminating several risk factors associated
with high pressure gases. Solid state lighting has advanced
dramatically over the past several years, and has become the
industry standard for a variety of lighting
applications.
Lighting Start-Up and
Cool-Down
During initial
start-up, the metal halide will fail to operate at the maximum
luminous output. The pressure and temperature within the
interior arc chamber may require up to five minutes to achieve
the necessary state for optimal performance. During this
warm-up period, the metal halide may exhibit numerous colors as
a result of vaporization occurring within the arc chamber. In
the event of a brief power failure, the arc will extinguish. A
cooling period as long as 12 minutes may be required prior to
restart. Unlike the metal halide, LED lights respond instantly,
and do not require a warm-up period. In the event of a
momentary power failure, the LEDs will resume normal operation
the moment that power is restored.
Metal Halide and LED Life
Span
A specific
metal halide features a 20,000 hour life, according to the
manufacturer's data sheets. Improper bulb orientation can
actually reduce the life by 5,000 hours. Near the end of life,
the bulb will begin to exhibit "cycling". As the lamp ages, the
required voltage increases beyond the available source voltage.
With increasing internal temperature, the lamp will fail. After
a brief cooling period, the lamp will re-start. This process
will then repeat on a continuing basis. Aging LED lights do not
exhibit similar behavior! An LED fixture designed to replace
metal halides in gas station canopies, can provide up to, or in
excess of 50,000 hours of life. The LED lights may remain
operational for as long as 100,000 hours, at a decreased
luminous output.
LED Lighting Heat Dissipation
LED lights
generate significantly less heat when compared to the metal
halide bulb. Not only do the LEDs generate less heat, but they
also dissipate their thermal energy back into the mounting
fixture. Most traditional light bulbs tend to dissipate heat
from the front of the bulb, and out into the surrounding
atmosphere. This can make thermal management a challenge in
certain applications where the direction of heat dissipation
becomes critical.
LED Beam Angle
Due to the
directional characteristics of traditional metal halides, the
bulb produces mass amounts of wasted light from the top and
sides of the lens. Not only does this result in a lower system
efficiency, but also contributes to environmental "light
pollution". In rural areas, metal halides can illuminate the
night sky, causing an eye-sore for nearby residents. However,
LED lights feature superior directional characteristics, and
can dramatically reduce night sky pollution. The narrow beam
angle featured on many LED lights provides illumination within
the intended areas only. Not only does this reduce light
pollution, but also promotes higher overall system
efficiency.
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