In the USA –
“Glass manufacturing accounted for 1%
of total industrial energy use in EIA's most recent survey of the manufacturing sector. Overall
fuel use is dominated by natural gas (73%) and electricity (24%), with the
remaining share (3%) from several other fuels. Natural gas use at glass
manufacturing facilities in 2010 was 146 trillion Btu, about 143 billion cubic
feet.
If we convert the natural gas to kWh,
we get:
143 billion cubic feet Natural Gas =
41,909,163,034.63 kWh
Annual output, 1,301 GWh (125 MW avg. power). Website topazsolar.com. Topaz Solar
Farm is a 550-megawatt (MW) photovoltaic power station in San Luis Obispo ...
Construction cost: $2.4 billion
Construction began: 2011
Annual output: 1,301 GWh; (125 MW avg. power)
Capacity factor: 24.4% (2014-2015)
From above:
143 billion cubic feet Natural Gas = 41,909,163,034.63 kWh
The Annual output of Topaz Solar Farm
is:
1,301 GWh = 1301000000 kWh
It would take 32 of these installations to replace the
energy
used for just the glass made in the USA in the year
2010.
That would be 288,000,000 solar panels.
10 Mahattans
Almost 46,000 Football fields.
The sun shines during the day and not every day.
So of course the energy would need to be stored
because glass factories run 24/7 365 days/year for up to 18 years.
The USA is only a part of the glass manufacturer
globally.
Even though
flat glass accounts only about 16% of the global glass industry, most
information on market structure focus on this segment. The global market for
flat glass in 2010 was approximately 56 million tonnes. This is dominated by
Europe, China and North America, which together account for around
three-quarters of global demand for flat glass. Of total global market demand
in 2010, it is estimated that 33 million tonnes was for high quality float
glass, 1 million tonnes for sheet glass and 2 million tonnes for rolled glass.
The remaining 20 million tonnes reflects demand for lower quality float,
produced mainly in China. The significance of China as a market for glass has
been increasing rapidly since the early 1990s as the country has become more
open to foreign investment and the economy has expanded. In the early 1990s
China accounted for about one fifth of world glass demand, but now accounts for
51%.
. .
. the energy intensity of
continuous glass furnaces in Europe and the United States were reported as 4-10
GJ/t of container glass and 5-8.5 GJ/t of flat glass.
Each
week, between 350 and 400 float glass lines
around
the world yield about 1,000,000 tons of glass.
The
Float Glass Process
The
dominant method of making flat glass is the float-glass process. First, after
mixing the raw ingredients in the batch house, they are fed into the furnace
and melted at 1550 °C. [2822F]
Thereafter,
the melted glass flows onto the top of a bath filled with molten tin at 1050
°C. [1922F] The atmosphere in the bath is a mix of
nitrogen and hydrogen that prevents the oxidation of the tin. Because tin has a
higher density than glass, the glass spreads out on top of the tin, giving it a
smooth, even surface. Some tin incorporates into the surface of the glass in
contact with the bath, this side of the glass is referred to the tin side, as
opposed to the air side. Next, the glass passes into the annealing lehr, a long
oven with a temperature gradient, where the glass is slowly cooled to 40 °C to prevent
it from cracking [14]. It is also possible to apply a coating (anti-reflection,
TCO, etc.) either within the tin bath or just after the tin bath via chemical
vapor
deposition.
Finally, the glass is inspected for defects, coated with Lucite separating
media to prevent scratches when the glass is packed and shipped, and cut to the
required size.
How Glass Is Made
1.58
Float
plants normally are sited near a silica source, and often near a customer’s facility, to
minimize transportation costs, which can be 15% of total costs. Also, they
often are built in areas with low electricity costs, since the float process is
energy-intensive; a plant uses 14 million therms (410 million kilowatt hours)
of energy per year.
Most
photovoltaic modules use glass. Crystalline-silicon technologies use glass
cover
plates
to provide structural strength to the module and to encapsulate the cells.
Thin-film solar technologies also often use glass as the substrate (or
superstrate) on which the device is built [3]. In fact, for the majority of
solar modules in production, glass is the single largest component by mass and
in double glass thin-film PV, and it comprises 97% of the module.
It is important to understand
that this is not the only high temperature process required for an industrial
world. See chart below.
