Kevin Tsukamoto

Professor Cogdell

Design 40A

March 13, 2013

Billboard Construction and Raw Materials

The average American is exposed to between 3,000 and 20,000 advertisements in a single day. These take on the form of almost every media type available, from radio advertisements, newspaper ads, television commercials, to online pop-ups ads and email spam. There is one form of graphic advertising in particular that Americans are exposed to every time they travel on the freeway or through downtown streets: billboards. Billboard advertising can be found along freeways, on top of buildings, or freestanding in any high traffic area. In fact, they are so common that most people view them like any other everyday object. And like a toothbrush or cellphone, we assume that the final object is all that makes up the device because it is the part we interact with. For every billboard built, there is a process by which raw materials are converted, combined, and shaped into the final advertisement that society interacts with. As a designer, it is critical to understand this process, and that every design decision affects costs, resources, energy input along the way. That being said, I would expect the average person would not consider how a billboard is made and what inputs are necessary. This is an attitude that needs to change. What is important is the fact that billboards, along with every single thing we interact with on a daily basis, are created using raw materials and energy over a process much more complex and costly than simply paying money and building a billboard.

Before going into the details of billboard production, it is important to clarify exactly what “billboard” means. In practice, billboards take on many different shapes and sizes; anything with advertising structure with a large display face can be considered a billboard. For the remainder of this paper, billboard will refer to the most common design in the industry: 14 by 48 feet, single-face vinyl and steel billboard, standing on a monopole 100 feet above the ground [Figure 1]. Single-face means the display only has one surface for artwork, as opposed to a double-face where there are two faces on either side of the pole for artwork. Monopole means the frame and display face sit on a single pole that is anchored in the ground. Although there are numerous structural elements that make up a billboard, the three major parts are the display face where the artwork is attached, the frame, which supports the display face, and the pole to which both sit (North Carolina Department of Revenue, 2009).

Billboard displays and frames can be constructed of various materials. Most commonly, steel and wood are used for the structure, and the display is cloth, wood, or vinyl (CBS Outdoor). Steel is one of the most important materials used in billboard construction, as it makes up the support frame and monopole to ensure the entire structure is sturdy and secure. Steel is an ideal material because it remains upright in heavy winds, and is light enough that it doesn’t collapse under its own weight (World Steel, 2011). There are many different types of steel and production processes vary amongst these. Furthermore, each process requires different raw materials as inputs. The two overarching categories of steel production are the following: primary and secondary methods. Each method uses different raw materials to produce the final steel product.

Primary steel production makes up about seventy-five percent of world steel production [Figure 2]. The raw materials used in this process are mainly iron ore, coal, limestone, and recycled steel. According to the World Steel Organization, this process uses about 1,400 kg of iron ore, 770 kg of coal, 150 kg of limestone, and 120 kg of recycled steel to produce one ton of crude steel. The first step in this process is preparing raw materials (World Steel, 2011). Iron ore is mined in over fifty countries, although Australia and Brazil have dominated the world’s iron ore exports with about one third of total exports each (World Coal Institute, 2007). Since, the cost of iron ore is about the same in many locations, the deciding factor for ore-based steelmaking production is often energy (Srivastava and Kawatra, 2009). Before iron ore can be made into steel it must be upgraded through a series of physical separation processes consisting of crushing, grinding, pelletization, and oxygen furnace. The main purpose of these processes is to prepare the iron ore for reduction in the blast furnace. The raw iron is sent through various crushers, grinders, and rollers. The material emerges in the form of iron ore pellets, round balls of iron of different sizes ready for reduction in blast furnaces (Everett, 2011). Steel production relies heavily on coal; 68% of production relies directly on coal input and the steel industry as a whole uses about 12% worldwide coal World Coal Institute, 2007). Before the coal is used in steel production, it must be prepared into coke. This is achieved by baking coal in an airless furnace. Next, the prepared iron ore and the coke are sent to the blast furnace of a direct reduction furnace for reduction and separation of slag (the non-useable mix of metal oxides) and molten pig iron (the iron that will made into steel). Blast furnaces are very efficient but they require high-grade coal. Direct reduction furnaces mostly use natural gas, and the iron never becomes molten. The iron is now acceptable for basic oxygen furnacing, or if direct reduction was used, electric arc furnace. Oxygen furnaces take the molten iron, coal, other metals and minerals like limestone, along with some recycled steel and melts it all into the new steel (Kopfle and Hunter, 2008).

Secondary steel production is much less common, only about 20% of the world uses it. In secondary production, the main raw materials are recycled steel and electricity (Srivastava and Kawatra, 2009). Recycled steel is gathered from excess material in steel factories and from discarded products (World Coal Institute, 2007). The process is much simpler than primary production: recycled steel goes into an electric arc furnace, and out comes the final material. Once the steel is out of the furnaces, it can be forged into the different parts need for billboard construction. Column, plate, torsion bar, outriggers, uprights, stringers, panels, skirting, bolts, and frame are some of the steel parts produced for the billboard [Table 3].

The second most important material used in billboard production is vinyl sheeting. This is the part of the billboard that everyone looks at, the part that has the artwork, and what really makes the billboard an effective advertising tool. Vinyl, an abbreviation for polyvinyl chloride, more commonly called PVC, is a polymer consisting of 34% hydrocarbons and 57% chlorine. Two of the key raw materials in PVC are salt, the chlorine source, and ethylene, the hydrocarbon source (Martinz and Quadros, 2008). Salt used in vinyl production is either extracted from the seas or mined in the land. Ethylene is a colorless gas obtained from either oil or natural gas. According to the article “Compounding PVC With Renewable Materials” there have been some interesting developments with the idea of making PVC more renewable and less dependent on oil. One example of this is the generation of ethylene from ethanol in sugar cane, eliminating the use of oil and natural gas (Martinz and Quadros, 2008).

Once the raw inputs of either natural gas or oil and salt are obtained, ethylene and chlorine must be extracted through tow processes, cracking—the extraction of ethylene from oil—and electrolysis of water and salt to make chlorine. The next step in the process is the chemical reaction between ethylene and chlorine to form ethylene dichloride [figure 3]. Ethylene dichloride is transformed into a gas called chloride monomer, which goes through a process called polymerization. Polymerization converts the monomer into a fine grain white powder polymer, referred to as polyvinyl chloride or vinyl (Martinz and Quadros, 2008). At this stage, the material is not ready to be sued for billboard art. The polymer must be combined with extra chemical additives and modifiers to get the final vinyl compound. The vinyl compound can then be used to make the large sheets of the display on a billboard (Martinz and Quadros, 2008).

Now that the display board, frame, and supports are made, there is still no artwork to display on the billboard. The images seen on billboards are most commonly created using a process called lithographic printing. In lithographic printing, ink and water are applied to the plate cylinder with the negative image, which is then transferred to a blanket cylinder to create the positive image, and from there printed on the vinyl held by the impression cylinder [figure 4]. To get the desired image onto the plate cylinder, an artist first draws the image on sheet of paper. Then, using a tool called a pounce wheel, the image is transferred in charcoal dust to a steel or aluminum plate. Through chemical processes, the desire image is made to hold ink and repel water, and the non-image area is made to repel ink and absorb water. This allows the image to be transferred to the blanket cylinder, so that only the ink contacts the vinyl (Dynodan, 2013).

Printing is a key part of billboard production, so it is important to consider all of the inputs that end up producing the final printed artwork. The main materials in this process are paper, charcoal, inks, and vinyl. Of these, the inks used in lithography are the most synthesized and contain the most additives. There are four key ingredients in the ink: pigments, solvents, vehicles, and additives (Dynodan, 2013). First, pigments, which come in both organic and inorganic varieties, are the dry particles that give ink its colored properties. Organic pigments tend to be more rich, bright and transparent, while offering a wider selection of colors compared to inorganic pigments. The majority of organic pigments are made from petroleum, and contain other raw materials like carbon hydrogen, coal, wood, animal fats, and vegetable oils. On the other hand, inorganic pigments are chemical compounds with different proportions of chemicals to determine different colors. These pigments are less expensive to produce but do not offer all of the characteristics desired that organic pigments do (Dynodan, 2013).

Next, the vehicle is the liquid part of the ink that holds the pigments, gives the ink its drying quality, and binds the ink to the vinyl after printing. Depending on the manufacturer, vehicles have varying compositions. Some are made from oils like rosin and petroleum, and others from hydrocarbon resins dissolved in petroleum solvents. Depending on what raw materials are used, the ink can have different drying properties (Dynodan, 2013).

Finally, several different ink additives complete the final product. A few examples of these are metallic salts like manganese and cobalt (to speed up drying), waxes like paraffin wax or beeswax, and cornstarch to thicken the ink (Dynodan, 2013). These various inks combined with the vinyl sheeting described earlier are what make up the advertising art on the standard billboard. As you can see, while the average person sees only words and images on the billboard, there are numerous raw materials and inputs that must be combined and transformed to get the final product.

Most billboards are designed to be viewed both during the day and at night for maximum impact on consumers. Therefore, it is common to install some sort of lighting element at the bottom of the sign. Fluorescent and incandescent elements used to be common, but more recently these technologies are being replace with LEDs. LED lights use less power and have a much longer lifetime than traditional bulbs, and ideal choice for billboard lighting (Scholand and Dillon, 2012).

LED manufacturing is an intricate and technical process that involves multiple companies at different stages of construction. LED production can be broken down into 3 main steps, each with different raw materials and resources: substrate production, die fabrication, and assembly (Scholand and Dillon 2012). [Figure 5]

The first stage, substrate production, prepares and polishes the cleaned sapphire wafers for die fabrication. An interesting point to consider at this stage is the amount of sapphire needed for each wafer. Through the processing of these wafers, much of the material is lost from polishing and sawing. According to the United States Department of Energy, a 3-inch, or 6 gram wafer requires around 11.1 grams of sapphire core. Besides the sapphire core, a 3-inch wafer required alumina, alkali detergent, diamond slurry, and water. Table 5.3 gives a list of all of the raw inputs and the quantity (Scholand and Dillon, 2012).

In the next phase of production the prepared substrate is put into a reactor for heating and the addition of two more layers. The wafer then goes through inspection and can be masked, etched, and finally the metallization of the contacts on the LED occurs. This is also the part of the process that separates the LED dies from the wafer so they can be ready for packaging. The number of inputs at this stage of manufacturing is quite large, consisting of various chemical and oxides (Scholand and Dillon, 2012). [Table 5-6]

Lastly, the third step in making LEDs involved mounting the LED die in its housing and making all of the electrical connections. Depending what the LED will be used for, in this case billboard lights, the required lens is also applied to obtain the desired effect (Scholand and Dillon, 2012). Table 5-8 displays the raw inputs of this stage. The LED elements are now prepared to be installed on the final billboard.

Once the numerous raw materials are processed, manufactured, and fabricated into the parts for the final billboard, the final step is to install the structure in the desired location. The most common way for monopole billboards to be installed is by drilling a hole in the earth, and filling it with concrete. This final step introduces new raw materials into the billboard making process. Concrete is a substance made of three main components: water, cement, and aggregate. Aggregate is the name for the sand portion of concrete usually made of crushed gravel, limestone, and recycled concrete. Cement is what gives concrete its binding property. Cement is made from two raw inputs, iron ore and clay, through process called calcification (Neville, 1995).

Finally, after all of these different processes, some highly technical, some more basic, and numerous raw materials, both natural and synthetic, we have the key components to build a billboard. The only process left is the deconstruction of the billboard. For the majority of billboards, the only part that is removed is the artwork, and new artwork is simply put up to replace the old. In some cases the new vinyl can even just be placed over the old. When a billboard does need to get demolished, almost all parts can be reused in some way. The steel components can be used as recycled steel for future steel production, in fact more steel is recycled every year than all other materials combined. By sector, steel recovery rates are estimated at 85% for construction, 85% for automotive, 90% for machinery, and 50% for electrical and domestic appliances (World Steel, 2011). As mentioned earlier, recycled steel is one of the main inputs in both primary and especially secondary steel production, making steel almost zero-waste. 98% of raw materials used in steel are converted to products or by-products that are used and recycled (World Steel, 2011).

What is important to understand is that this analysis of billboard production only goes so far. At each step in the process, and with each primary and secondary material, there are hundreds of other inputs that impact production in some way, and even more materials used to build or harvest those inputs. The investigating I did in this paper required a lot of piecing things together, as there is not a lot of information specifically about billboards and raw materials. I tried to get a good understanding of the components of a billboard, and then investigate those independently, combining my findings to conclude the complete process. One of the toughest challenges was finding information not related to the industry or the commercial companies. That being said, I feel like I portrayed the life cycle and materials as best as I could with the time and resources I had. Through the research in this paper, I hope to communicate the fact that the designed products we interact with every day have much more inside of them than what it appears from the outside. Because of this, it is important to consider all processes and inputs when designing such a product, and what it all will cost.

Bibliography

“Analysis of economic indicators of the EU metals industry: the impact of raw materials and energy supply on competitiveness.” European Commission, 2006

“Billboard Structures Evaluation Guide.” North Carolina Department of Revenue. 2009

Coal & Steel Facts 2007, World Coal Institute, worldcoal.org

Everett, J E. "Ore Selection And Sequencing." Applied Earth Science: Transactions Of The Institution Of Mining & Metallurgy, Section B 120.3 (2011): 130-136. Academic Search Complete. Web. 23 Feb. 2013.

Kopfle, John, and Robert Hunter. "Direct Reduction's Role In The World Steel Industry." Ironmaking & Steelmaking 35.4 (2008): 254-259. Academic Search Complete. Web. 20 Feb. 2013.

Martinz, Daniel, and J. Quadros. "Compounding PVC With Renewable Materials." Plastics, Rubber & Composites 37.9/10 (2008): 459-464. Academic Search Complete. Web. 27 Feb. 2013

Neville, AM. “Properties of Concrete: 4th Edition.” 1995. February 13 2013.

"Printing Process Explained - Lithography." Dynodyn.com. N.p., n.d. Web. 11 Feb. 2013.

Srivastava, U., and S. Komar Kawatra. "Strategies For Processing Low-Grade Iron Ore Minerals." Mineral Processing & Extractive Metallurgy Review 30.4 (2009): 361-371. Academic Search Complete. Web. 20 Feb. 2013.

“The State-of-the-Art Clean Technologies (SOACT) for Steelmaking Handbook.” Asia Pacific Partnership for Clean Development and Climate, December 2007.

United States. Department of Energy. Life-Cycle Assessment of Energy and Environmental Impacts of LED Lighting Products. By Michael J. Scholand, LC and Heather E. Dillon, Ph.D. Pacific Northwest National Labratory, 21 Aug. 2012. Web. Feb. 2013.

World Steel Fact Sheet: Raw Materials. World Steel Association. 2011. worldsteel.org

Amanda (Mandi) Saeteun

DES40A: W13 – Professor Cogdell

13 March 2013

Highway Billboards: Lifespan Production and Embodied Energy

Today’s designers are constantly working to innovate the products of tomorrow. They must design inventively, efficiently, and most of all, responsibly. People enjoy the ability to have the newest products on the market, but do they consider all of the energy consumed to produce the item? And what happens to the added waste of the products they no longer use? Sustainability is now an essential component required of designers in all fields. Using renewable materials and keeping a minimal impact on the environment are principles of sustainability. With the development of more and more products, this component of design cannot be ignored as it is becoming more relevant and impactful for the generations to come. With the consideration of sustainability comes the theory of “embodied energy.” This theory looks at the entire lifespan of a material and measures its total energy consumption. By applying a general understanding of this theory, we will attempt to identify the types of energy consumed in a product we see everyday: traditional highway billboards.

The theory of embodied energy is used most often by builders and architects today. With this theory, they are able to determine the energy costs of renovating an existing building versus developing an entirely new structure (Pfaehler, 2008). They focus on the energy required in the building of materials, construction processes, and their environmental impacts. For the purpose of our study, we will try to find the areas of energy consumption in a similar breakdown. We will evaluate more specifically the production, distribution, and the disassembly and recycling processes of traditional highway billboards. Through this analysis, we can establish an educated awareness of how energy is used to give life to the products we often take for granted. Before moving forward with our research, it is important to first define the specifications of the product we will be focusing on in more detail.

The outdoor advertising industry is estimated to cost over $5.5 billion a year in the United States (Outdoor Advertising Association of America). Development of roads and highways has allowed for the market to continually flourish – new roads mean more real estate for advertising. Outdoor advertising includes displays seen on the tops of taxicabs, exterior wraps on large buses, and even draped signage on the sides of tall metropolitan buildings. Although people don’t always take note of every single advertisement they come across, they are relentlessly being exposed to it on a daily basis. With an ability to reach 93% of Americans, traditional highway billboards continue to be the most sought after method for outdoor advertisers. For the remainder of this research paper, we will be examining the energy consumption for the following specified structure: 14 by 48 feet, single face, monopole, 100 foot pole, vinyl, billboard. 14 by 48 feet is the industry size standard offered by many of the largest companies in outdoor advertising (Lamar Advertising Company, CBS Outdoor). Billboards also come in several types of classes or structures: wood, steel, multi-mast, and monopole (North Carolina Department of Revenue, 2009, Exhibit A). Although the monopole come in different builds including V face, double face, and triangle, we will be looking particularly at the single face design (North Carolina Department of Revenue, 2009, Exhibit B). Due to the billboard’s large dimensions, a 100-foot pole is required to withstand calculated wind-blow capacities. Finally, due to its easy production process and lightweight features, vinyl has become the preferred material for large billboard printing. To clarify, both the energy consumed in the billboard frame and vinyl production processes will be examined within this research. With a foundation of the billboard specifications provided, we can begin to study the energy consumption within each of the following phases of highway billboards: production, distribution, and disassembly and recycling.
Production (Raw Materials & Manufacturing):

Before a product can be enjoyed by the masses, much thought and consideration goes into the process of production. Production includes the extraction of raw materials and manufacturing. For highway billboards, this process will include the building of the steel frame structure and the printing process of large vinyl billboards. Monopole steel frames are generally made of tubular steel supports (structure), poured concrete (foundation), a platform or catwalk (within the base), and a lighting system (within the base). After the completion of the billboard’s infrastructure, a large vinyl banner is produced and later installed.

The first component in the production of highway billboards is the steel frame structure. The three main materials used to manufacture steel are iron ore, coking coal, and scrap metals or limestone. With the thermal energy created by iron ore and coking coal, scrap metals are recycled and melted down for the use of steel making (World Steel Association). If recyclable scraps are not readily available, limestone is extracted as a raw material (World Steel Association, Steel University). The materials are then formed to the intended fabricated shape through heating, shaping, joining, and coating. According to the United Nations Environment Programme, 95% of the energy required for making steel is found in coal, 3-4% from gaseous fuels and 1-2% from liquid fuels (UNEP, 1997).

The second component to the billboard production process is poured concrete. The concrete secures the billboard’s structure to the site location. This also ensures the structure can withstand time and difficult weather conditions. To achieve this, a hole is drilled into the ground to reach a distance of 20 to 30 feet. The depth of the hole is important to bear the heavy 100-foot pole and the calculated wind blow capacities of the given region. A drill attached to a truck (sometimes referred to as a Digging Derrick Truck or line truck) drills the hole to the specifications of the design. Concrete created from aggregate (varieties of crushed stones), cement (crushed and burned limestone, or other minerals), and water is then combined in a mixing truck (Lamb). Through the process of hydration, the three components turn into a thick paste, ready to then be poured to set the foundation for the pole to stand in. Energy required in the extraction process includes kinetic (crushing, refining materials within aggregate and cement), chemical (to fuel the industrial machines), and thermal energy (1400-1600°C to create concrete) (Department of Materials Science and Engineering). For the assembly process, chemical energy is used (in petroleum fuel) enables drilling into the earth, and kinetic energy allows for pouring of the concrete mix. Exhibit C helps to illustrate the magnitude of the construction process. Once the billboard’s steel frame pieces are configured and infrastructure has been laid down, the catwalk or platform is applied.

In order for advertisements to be replaced for different clients, a platform or catwalk has to be developed. The platform is designed to allow for professionals to walk across the front of the face of the billboard. This component is usually made of steel or aluminum and designed to have a diamond pattern to avoid slipping (McGraw Hill Construction, Exhibit D). Since the process of steel production was mentioned previously, we will look only at the aluminum production process in this section. To create aluminum, aluminum oxide (or synthetically made alumina) is combined with electricity and carbon. Through carbon anodes, hundreds of thousands of amps of electricity are sent, reducing the mixture to aluminum particles. With the application of thermal and electric energy, the remaining particles are then smelted at 730°C (New Zealand Aluminum Smelters Limited). The liquid aluminum is then molded into the desired shape. Because of the billboard’s large scale, the pieces may have to be transported in several pieces and installed on site.

A component essential to showcasing the billboard’s advertisement is the production of a lighting system. Similar to the installation of the billboard’s steel pole, electrical engineers are contracted to ensure that all local authority codes are met. Engineers use various electricity reading tools, digging trucks and cranes, and computers to install electricity to a given area. This process requires kinetic, thermal, and chemical energy. With the infrastructure for electric power developed, lighting fixtures can be placed onto the billboard frame (Exhibit E). The most common choice for lighting used today is the light emitting diode, more commonly known as LED. Developed around 1963, LEDs were primarily used for Christmas lighting. Today, engineers have redesigned and applied its use on a much larger scale. LEDs are now one of the most energy efficient and rapidly developing light technologies (Department of Energy, 2012). They are generally made up of two electrodes (an anode and a cathode), a whisker, an anvil, a semiconductor, and a lens. All of these items are then contained within an epoxy resin case (eHow). Because LEDs are used in home, commercially, and industrially, manufacturing of the product vary as well. Though the initial price of production may be expensive, LEDs will continue to be the choice for lighting systems as they can last 25 times longer than a traditional incandescent bulb and use 75% less energy (Department of Energy, 2012). Due to the continuing development of LEDs, resources on energy costs of production are limited. However, since the use of LEDs is becoming more common, there are lots of studies on the energy input and outputs of LEDs versus traditional light sources. Exhibit F further illustrates the high efficiency of LEDs in their minimal inputs, and high yielding outputs (Department of Energy, 2012). With the main elements manufactured, the final component left for production is the vinyl banner.

In the past, billboard advertisements were made up of hand painted images or individually glued panels. With the development of large-scale printers, digital designs are now directly printed onto large sheets of vinyl allowing for easy installation (Exhibit G). The ability to apply vinyl banners to a billboard involves a two-step process: 1) vinyl manufacturing and 2) printing. Vinyl is made of resin derived from polychloride vinyl (PVC), a widely used type of plastic (Encyclopedia Britannica). In its most basic reduction of raw materials, PVC consists of rock salt and crude oil. Through complex chemical processes, lubricants, polymers, pigments, and stabilizers are eventually added (PVCplus Kommunikations GmbH, 2012). Depending on its intended purpose – anything from pipes to thin clear-wrap for food packaging – the process and additives vary. As a result, the ability to investigate the total energy consumption in vinyl production is difficult to find. It can be said however, that kinetic, chemical, thermal energy is utilized in the production process. These energies are used in the extraction of raw materials, chemical process of PVC production, and again in the sheet formation of thin vinyl. A quick video in the vinyl sheet making process helps to illustrate the production process (mixing, adhering, pressing) of PVC to vinyl sheets: Exhibit I. Once the vinyl sheets have been manufactured, printing companies order them for print production.

Although we are familiar with the printing process of traditional home office inkjet printers, vinyl printers are different, as they require special ink formulated to withstand harsh weather conditions. The ink is applied to the vinyl through large scaled printers previously shown Exhibit H. Through the use of low heat LEDs, the liquid ink is solidified onto the vinyl. This method is made possible through use of ultraviolet (UV) light (Echod Graphics). To give it durability, the vinyl is coated with a UV protectant and sealed with thermal lighting similarly seen in Exhibit J. Chemical, electrical, and thermal energy are consumed within this process.
Distribution (Construction & Transportation):

Unlike other tangible products such as phones or shoes, billboards do not require frequent distribution costs of energy. As a result, most of the distribution costs of energy are in the initial construction of the billboard’s structure. Once all of the billboard’s structural and vinyl elements have been fabricated, they are transported to the site for installation. Whether the transportation occurs by plane, boat, train, or truck, a form of petroleum (chemical energy) is required to provide power to move the heavy components. At this point in the billboard production process, the steel erecting company is often contracted to build the remaining structure (How Products are Made, Volume 5). Exhibit K illustrates the installation development, including the billboard’s frame construction and electrical requirements. This requires kinetic energy for installation, fuel (chemical energy) for mobility of the large structural pieces, solar energy (thermal energy from the sun) to set the concrete, and electrical energy to power the light system. After installation is finished, drivers are able to consume the messages of the advertisement during their daily commutes. As such, energy costs are not frequently imposed for packaging or distribution. With new advertising clients; however, there are additional energy costs required for the fabrication of the new sign and installation process.
Disassembly (Disposal & Recycling):

It is important to remember that energy consumption does not end here – a product’s lifespan includes disassembly and recycling process as well. As with most large scaled structures, demolition includes the use of large cranes or bulldozers. Once the pieces are broken down to manageable sizes, they can then be transported for disposal and recycling. This would employ the use of kinetic and chemical energy. As mentioned in the steel production section earlier, scrap steel is often recycled and broken down to create more. With the use of high thermal energy, it can be remolded for a new use. The second component to the billboard is the vinyl banner. Believe it or not, there are sustainability companies asking for the donation of used vinyl (Exhibit L). Companies then create bags, purses, or notebook covers since its qualities are similar to fabric material. Although the energy required to convert the recycled steel and vinyl materials vary, thermal (to melt), chemical (sealants), and kinetic (human force) energy can again be applied to achieve its transformation. Anything that cannot be recycled is sent to the disposal for further processing. Because of the billboard’s durable components of vinyl and steel, they should not require frequent disassembly. The profit is found in its ability to withstand time thus allowing its building costs to be repaid. They achieve this through the marketing of the billboard’s location or real estate. According to Lamar Advertising Company, a 4-week running advertisement in a 14 by 48 foot space can range from approximately $4,000 to $97,000 (Lamar Advertising State Rates). The space rental rates are dependent on the amount of traffic flow and location.

With a better understanding of the lifespan and energy consumption of highway billboards, we can hopefully come to appreciate their availability much more. With the technological advances made through the years, we are able to erect 100 foot steel poles, dig 30 foot deep holes into the earth, supply light to empty fields of dirt and grass, and display 48 foot banners for many people to see. This is no easy feat. The lengthy process detailed above used the following types of energy: thermal, kinetic, chemical, and electrical energy. However, through its total lifespan, one particular energy source was required the most – chemical energy found in oil. The heavy machinery needed for the production (cranes, trucks, raw material conversion process, transportation, installation) uses fuel as its main energy source. Unfortunately, oil is a non-renewable material. Formed from deep within the earth, oil is drilled and pumped from saturated wells or pockets. After extraction, it is then put through a distillation process to separate byproducts and prepare for regular usage. Although oil is produced in Mexico and Alaska, most of the United States’ oil is obtained from overseas. 40% of the oil demanded is used for energy, 99% of that amount is then consumed for transportation purposes (Pennsylvania Historical and Museum Commission). As the energy consumption in billboards suggested, the most necessary materials and tools in the production are dependent on oil. What happens when this resource is no longer readily available?

Though the production process of billboards cannot likely function without the use of oil, there were some sustainable ideas already implemented within the production process I would like to revisit. As I mentioned, steel and PVC are currently being melted and remolded for new uses. Steel continues to be North America’s number one recycled material, along with paper, aluminum, glass, and plastic (Steel Recycle Institute). The lighting systems slowly being implemented include LEDs, a source that is estimated to last 25 times longer than traditional incandescent lights. With widespread use of LEDs in the United States, the Department of Energy has projected a total savings of $30 billion by 2027 (Exhibit M – Department of Energy, 2012). Lastly, with the continuing development of more efficient technology, tools such as UV printers allow for more durable products. Vinyl banners created with UV printers have longer lifespans that are estimated to last up to two years without fading (Echod Graphics). These may seem like tiny steps to progress in comparison to the huge amounts of energy consumed through the lifespan of billboards, but it reflects a growing consciousness and concern for sustainability. Before we can begin to criticize consumers or manufactures for the growing availability of products, we have to ask ourselves: is the transition towards sustainability that simple? Alice Rawsthorne’s statement accurately illustrates the challenges of sustainability today:

Sustainability isn’t just sort of a glamorous process of using recycled materials to design something that may or may not be the color green. It’s about redesigning every single aspect of a company’s process, from sourcing materials to designing to production to shipping, and then eventually designing a way for those products to be disposed of responsibly. That’s a mammoth task, so it’s no wonder that designers and manufacturers are finding it so difficult.

Failures & Assumptions:

This energy section was more difficult than I had initially thought. As a person who lacks thorough education (and attention span) for science and physics, I was unable to confidently come to definite conclusions regarding some of the energies required in billboards. With my independent research and the knowledge provided from class, I attempted to apply the concepts I was familiar with. Although I was happy with the vast background information I found on the construction of the billboard’s structure, I struggled with the ladder parts, specifically in regards to LED and vinyl. I did, however, stumble across some hidden gems worth viewing in the Exhibits provided below. I hope they help to illustrate the lifespan of highway billboards in ways I couldn’t articulate.

I also posed a few questions to the reader in the conclusion of my essay. I have my own theories about sustainability, and intended only to elicit thought and contemplation from my reader – not to provide a simple solution. As we know, several other essays can be written on the topic of petroleum alternatives and the implementation of sustainability’s core principles. I hope that my doing so seemed intentional.

In hindsight, it also would’ve helped if our group chose a single product without so many components. With the billboard, we had to cover the infrastructure, steel frame, installation, catwalk or platform, vinyl production and print, and lighting system. I tried my best to capture the most important ideas that related directly to energy.

Works Cited

OutofHomeAdvertising.aspx

“Billboard Construction/Maintenance.” Waterway Outdoor, LLC. March 3, 2013. http://www.waterwayoutdoor.com/waterwayoutdoor/?page_id=23

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“Billboard.” How Products Are Made, Volume 5. February, 6, 2013. http://www.madehow.com/Volume-5/Billboard.html

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Exhibit I: Calendaring Process for PVC

Exhibit J: How UV Coating Works: Making It Shine!

Exhibit K: Billboard Construction/Maintenance

Exhibit L:

Gorilla Sacks

Green With Envy Gifts

Jennifer Wu

Professor Christina Cogdell

DES40A

15 February 2013

Wastes and Emissions of the Standard Billboard

Designing a product is very similar to having a newborn baby: everything that enters the baby’s mouth must be accounted for and the resulting waste properly handled and disposed. Specifically for the billboard, it is vital to understand not only the components that go into the production process, but also the resulting waste emissions and environmental consequences. Although billboards might not keep us up all night with fretful crying, it is no trifle how the waste removal process is conducted, as it may ultimately affect us all in the long run. Through examining every aspect of the production line, the accumulating waste, and the disposal techniques in effect today, we see that billboard production entails more waste than previously thought.

The billboard being examined will be the standard 14x48 ft. single-face monopole vinyl billboard elevated 100 ft. off the ground and analyzed (production-wise) from the ground up. The first step to consider in the billboard production is the drill rig, which creates a 20-30 feet deep hole for the concrete and support column to be placed in (How Products Are Made). The standard drill rig runs on hydraulic oil, which can be subcategorized into the materials used to create the oil such as “mineral oil, organophosphate ester, and pholyalphaolefin” (Agency for Toxic Substances). There are biodegradable forms of hydraulic oil, which use a vegetable oil base such as rapeseed oil; however, this alternative is mainly used when dealing with agricultural purposes, not with constructing billboards. The main concern with hydraulic fluids would be the environmental damage caused if there is a spill or a leak within the machine. The fluids could infiltrate the soil, the groundwater, the grass, and eventually, make its way into the wildlife surrounding the spill and/or evaporate into our atmosphere (Agency for Toxic Substances). There are not many studies that concentrate on the harmful effects of consuming wildlife that has been contaminated with hydraulic fuel, but it is safe to assume no good comes out of it.

The next step of billboard production is filling up the hole with concrete with a concrete mixer to set the column in place. Normally overlooked, concrete is still a vital component in assembling a billboard: the ingredients and methods of producing concrete are things to consider when inspecting the waste removal process. Renting out a concrete mixer truck would be first step of this procedure. The main concerns about using a concrete mixer truck would be the diesel/gasoline emissions resulting from idle time keeping the concrete mixed or transporting the concrete to the billboard destination, and cleaning out the concrete compartment once it is done being used. Concrete mixers were determined to be one of the 5 least fuel efficient single-unit body types and ranked one of the top 10 fuel consumers based off of a study done at the Center for Transportation Research, Argonne National Laboratory (Gaines, Vyas, and Anderson, 2006). To have a better understand of what concrete is, it is important to know exactly what it is made of. Concrete is usually made up of cement, aggregate, and water, with water the sole ingredient that is not dangerous in terms of waste. According to the U.S. Department of Energy, “more than 60% of the carbon dioxide emissions from industrial sources originate from cement manufacturing”, being one of the largest sources of carbon dioxide emission in the United States and second only to fossil fuel consumption (Documentation for Emissions, U.S. Energy). Unfortunately any conversion from natural to synthetic material can have negative consequences, such as a waste product that cannot be easily disposed of. Once the hole is filled, there is the matter of cleaning the mixer. Cleaning the mixer can be done one of two ways, by hand with hammer and chisel, or with a water pump (Concrete Mixer). Chiseling concrete is a tedious chore, not to mention hazardous as well. Workers are in danger of falling cement pieces and becoming ill due to breathing in silica, a well-known carcinogen (Concrete Mixer). Water pumps, on the other hand, are safer, more reliable, and faster than the former; it does, however, create pollution because it runs on diesel fuel, consuming around fourteen to fifteen gallons per hour when in operation (Concrete Mixer). It can make one wonder if there is a safer alternative to concrete or if there are any means of creating a similar material less harmful to the environment.

Shifting the attention away from the waste process of concrete, it is now time to focus on the 100 ft. tall steel pole set into the concrete and the steel frame that is set on top of it. It is hard to find much information about steel manufacturing for billboards, which proves the fact that there are elements of the billboard design process that are missing and therefore need to be studied further. However, a hypothetical analysis can be made based on information that could be found. Steel is derived from iron ore once the impurities are all removed; the strength of steel is based on how much of these impurities are taken out. There are different ways to create steel such as the open-hearth furnace, the Bessemer process, the basic oxygen furnace, etc. (Brain and Lamb 2000). The one which most modern steel plants use is the basic oxygen furnace. It is preferred over the others for its speed (up to 10 times faster than an open hearth furnace), its lowering of “carbon, silicon, manganese, and phosphorus levels”, and “the addition of chemical cleaning agents called fluxes to help to reduce the sulfur and phosphorous levels” (Brain and Lamb 2000). Steel production, however, cannot be assumed to be environmentally conscious based off of that statement. There are key issues such as water pollution, air pollution, and energy consumption that need to be addressed. The best way to analyze the steel production process would be to start at the source: iron ore mined from the earth. Iron ore is normally surface-mined, utilizing heavy machinery to access the ores underneath the earth. The main concerns about mining have to do with disposing its waste material, land erosion, air pollution, and water pollution. Air pollution can be caused through explosives used to open up areas for mining, the heavy equipment used to extract ores or remove waste (polluting nitrogen oxide, carbon dioxide, and hydrocarbon), the dust that accumulates, and deforestation (Mining, Shastri). Water pollution can be caused by acidic discharges through acid rock and mine drainage, solvents from beneficiation activities, and contamination of ground water (Mining, Shastri). Once iron ore has been mined, it is then melted in the furnace to be processed into steel. The main fuel source to melt the iron ore is coke, coal processed to contain no impurities to become a pure carbon. The process of creating coke is unfortunately environmentally detrimental as well. The consequences of creating coke include emitting methane, ammonia, hydrogen sulfide, polynuclear aromatic hydrocarbons, hydrogen cyanide, and sulfur oxides (Environmental Engineering). Another issue would be the solid waste that comes out of the process; tar residuals need to be disposed of properly, recycled, or taken to the landfill. Methods that can be undertaken to reduce air emissions would be installing fabric filters wherever gases are released, using larger ovens to increase batch size and reduce emissions, and using coke-less iron for steel making (Environmental Engineering). The next item required to create steel would be some sort of flux, such as limestone. The limestone is vital because it is the agent which absorbs the phosphate from the iron, creating what is called a basic slag. Basic slag is not a byproduct to worry much about because the slow releasing phosphate of the slag acts as a great fertilizer that can be distributed to nearby gardens and farms (Heavy Industry).

Once steel has been produced, it is transferred to a steel casing where it is molded and rolled to create the desired shape. The steel needed for the billboard would be used for the frame, column, plate, torsion bar, outriggers, uprights, stingers, bolts, and panels (Rolfe). Steel molding does produce waste, but most can be recycled back into the steel-making cycle. However, one byproduct that cannot be recycled is waste treatment plant sludge. Unfortunately, because it is such a small portion of the entire process, it is often overlooked in terms of searching for a green steel-making method and little research has been done on it. While it is difficult to find information on where the steel parts were purchased from, it can be safely assumed that the parts were shipped from China. According to Richard McCormack, “China's government-owned steel industry has reached a new level of domination, accounting for 46 percent of global steel production” (McCormack). The underlying issue with transporting steel from China would be the waste emissions from the ship needed to transfer the material. Cargo ships transporting these goods are known to be responsible for almost 4 percent of the world’s climate change emissions, 30 percent of the world’s nitrogen oxide pollution, and uses up around 350 tons of fuel a day in an 11 day trip (from China to the United States) (Voelcker). That trip alone, to transfer steel parts from China to America, would use up around 7,700 tons of fuel for a roundtrip, a ridiculous amount when there are factories in the United States that provide the same parts.

Now that the frame has been shipped over and mounted on the column, the next step would be to attach a lighting mechanism so the billboard can be viewed by nighttime traffic. The preferred lighting of choice would be four 400W metal halide fixtures. This form of LED lighting is more efficient than others because LEDs reduce electric consumption by over 80% (Behrens). Bill Behrens, creator of “NewLight LED”, informs the reader of the benefits of using LED lighting: reduced electricity bills, low maintenance costs, reduced electrical loads, and reduced emissions damaging the environment (Behrens). However, exactly how beneficial the LED alternative is poses a question. LED lighting is known to be more environmentally friendly compared to normal lighting, but its green, eco-friendly title cannot be taken to heart. Companies manufacturing LED products do not disclose the methods of production, even though it is known to be causing the most environmental damage out of the whole process. The media only covers the positive effects of LED alternatives, making it difficult to find research on the negative impacts it might have. However, an article did come out about the lead, copper, nickel, and arsenic content known to be inside LED bulbs, claiming that broken bulbs can lead to water contamination as copper finds its way into nearby lakes and rivers and cancer-causing carcinogens when fumes are breathed in (Gabel).

The other environmental impact to consider would be the electricity needed to light these billboard fixtures. Three main concerns about coal-powered power plants generating energy pertains to the air pollution, water pollution, and solid waste that comes out of the process. Because power plants are fueled by large amounts of coal, they also emit a great amount of carbon dioxide; this greenhouse gas is connected to a widely known concern of the 21st century: global warming (Environmental Impacts). Global warming is not the only concern, unfortunately, because there are other problems that derive from it; rising temperatures disrupt the delicate balance of nature by (in order of causality) causing glaciers to melt, sea levels to rise, ecosystems and water currents to shift, and through this, alter the way we live (Bloom). Water pollution is created because power plants require a large supply of water, and through the process, the water becomes contaminated through the addition of heat, acids, and salts (Environmental Impacts). Because the water later goes through the sewage systems and into the nearby bodies of water, it affects the ecosystems around it and contaminates the wildlife (Environmental Impacts). Lastly, there is the matter of disposing the solid waste product that comes out of the power-generating cycle. Sludge and ash are the two main concerns with the non-recyclable byproducts, and are usually dumped at landfills either on-site or off (Environmental Impacts). Keeping large amounts of ash is dangerous, however, because it does contain radioactive elements and coal-ash spills have not been uncommon in the past.

The final step would be the actual advertisement, which would be inked onto vinyl sheets to be pasted onto the billboard panels. Vinyl, better known as, polyvinyl chloride (PVC) is one of the most widely used plastics due to its versatility and its low costs. PVC, however, is also one of the most toxic plastics currently inhabiting the Earth (Go PVC). Even though there are many safer alternatives that can be turned to such as “clay, glass, ceramics, and linoleum “, they end up being rejected because plastic is readily available, easy to manipulate, and very cost effective (Go PVC). The vinyl sheets are printed with a type of ink using an automotive grade pigment because it can last up two 2 years without fading from harsh sunlight, heavy rain, and gusty winds. Not much information can be found about these specific types of ink, except that it contains toxic, volatile organic compounds which come in the form of chemical solvents (Environmental Issues). These inks are most likely contained within printer cartridges to fuel the enormous billboard-specific printers. The problem with these ink cartridges is that it is not always recycled and reused. They usually end up in landfills where they are burned; burning these cartridges, however, “emits dioxins and polycyclic aromatic hydrocarbons (PAHs), both cancerous pollutants that pollute local rivers and lands, make their way into the food chain, and affect all levels of species” (Environmental Issues).

Once billboard production and distribution is finished, the only concern left is taking apart the billboard once it has served its duty. Steel parts and vinyl sheets are readily recycled and reused, so the billboard does not have much waste accumulation during the removal process. The manufacturing of the billboard, however, is a completely different story. The electricity used, transportation means, materials used, and other production processes all adversely affect the environment we live in, and the fact that not many people are aware of the waste implications of everyday objects is unsettling. Now that the lifecycle of the common billboard has been analyzed, the question to ask is whether it is possible to build a more environmentally friendly billboard.

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