Travis AFB Sustainability Study Report Final Background Report | Page 209
Light and Glare (LG)
Potential for glint and glare from solar arrays
This factor refers to man‐made lighting (street lights, airfield lighting,
building lights) and glare (direct or reflected light) that disrupts vision. Light
sources from commercial, industrial, recreational, and residential uses at
night can cause excessive glare and illumination, impacting the use of
military night vision devices and air operations. Conversely, high intensity
light sources generated from a military area (such as ramp lighting) may
have a negative impact on the adjacent community.
ISSUE
LG‐1
Key Terms
Glare (glint). The presence of excessively bright light, such as direct or
reflected sunlight, or artificial light, such as sport field and stadium lights at
night. Glare reduces visibility and can completely impair vision when very
intense.
Compatibility Assessment
Solar energy development is growing in use as technology becomes more
readily available. In an area such as California, solar energy development is
a practical alternative to fossil fuels. While the best areas for solar
development in California are concentrated in the southeastern portion of
the state, there has been some development of solar arrays in
Solano County.
Light Pollution. This type of pollution is created by the artificial brightening
of sky caused by development, including street lights and other man‐made
sources. This has a disruptive effect on the natural cycles and inhibits the
observation of stars and planets and can render night vision devices
ineffective.
In April 2009, SunEdison installed a 1.2‐megawatt solar array on six acres at
the Anheuser‐Busch brewery. The Fairfield‐Suisun Sewer District
Wastewater Treatment Plant, near the brewery, also has a one‐megawatt
solar array. Both systems are located approximately eight miles to the west
of Travis AFB. Other businesses have installed private solar arrays, including
Meyer, Alza Corporation, and Novartis in Vacaville. In September 2013, a
1.1‐megawatt solar array was installed at the North Bay Regional Water
Treatment Plant. The system, located about two miles northwest of
Travis AFB, covers seven acres and uses technology to rotate the solar
panels to follow the sun’s path.
Technical Background
The amount of ambient light experienced on the ground is a function of:
Intensity of nearby light sources (up to 20 miles away);
Distance from the sources;
Spectra of the light sources (blue light decays faster in the
atmosphere);
Density of the cloud deck;
Height of the cloud; and
Relative humidity.
When measuring light pollution, the proximity to a community has a
significant effect on the amount of light pollution that saturates the sky.
Proximity twice as close to a community makes its sky glow appear
approximately six times brighter.
TSS Background Report
There is a potential that new solar energy development
could cause glint and glare that could impact pilots’
vision. The County has adopted an ordinance that
minimizes this potential in unincorporated areas by
requiring detailed study of glint glare impacts from
potential projects. Further, the County has adopted an
ordinance that limits commercial solar energy
development on agricultural land.
One of the biggest future solar projects in the area is the future Ryer Island
Solar Farm, which will be installed and operated by SolAgra, and will begin as
a 2.2‐acre project of solar panels and a research facility. SolAgra stated they
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