Design Life-Cycle

Emma Hopson

Sustainable Design Course

University of Colorado Boulder, ATLAS Institute

Instructor: Eldy Lazaro Vasque

Life-Cycle Assessment for STEM Cider’s Hard Apple Cider

Brewing hard cider is a fascinating process that blends traditional brewing practices with innovation, resulting in a gluten free drink enjoyed by many. At its core, the art of crafting hard cider requires a thoughtful selection of raw materials, each playing a crucial role in shaping the final flavor and character of the beverage. The primary ingredient, apples, serves as the foundation upon which the entire process is built, with different varieties contributing unique nuances to the cider's taste profile. Alongside apples, yeast emerges as a key player, transforming the natural sugars present in the apple juice into alcohol during fermentation. Water, often overlooked but essential, acts as a canvas upon which the flavors of the apples and other ingredients are painted, while additional elements like sugar, tannins, and acids offer depth and complexity. As we delve into the intricacies of cider making, understanding the significance of these materials will help us understand the environmental impacts and life-cycle of the whole brewing and distribution process. This essay explores the intricate process of brewing hard cider, highlighting the fusion of traditional methods and innovation, while emphasizing the importance of raw materials selection, embodied energy and waste management and their environmental impacts throughout the lifecycle of production and distribution, with a focus on STEM Ciders. 

This information will be based on the brand, STEM ciders, who brew out of Lafayette, Colorado. However, it is important to note that despite several communication attempts they have not reached back out to provide specific details or comments. All of the information below is taken by assuming they use the industry standard practices during all steps of the process. Certain assumptions will be made about the origin of their ingredients. 

The first step in the life-cycle of a can of hard cider is the brewing process. This step takes in all of the delicious ingredients and turns them into the hard cider that is ready to be canned and distributed. The main ingredients for most hard apple ciders are the apples, yeast, water, and sugar. Let's first examine the apples that are used for brewing.  The United States is the second largest apple producer in the world, following only China. About 95% of the apples purchased and consumed within the United States are grown in the US(“Apples”). The top seven apple producing states according to USApple, are Washington, which produces about 62% of apples in the US, followed by Michigan, New York, Pennsylvania, California, Virginia, and Oregon. While all 50 states have apple orchards, the combined market production of apples from the other 43 states produce only 5.4% of the apples in the US (“2023 Apple Crop Estimate.”). This can lead to the assumption that STEM ciders probably get around 5-15% of their apples locally and the rest shipped from either Washington, Michigan or New York. As for their Colorado sourced apples, Colorado has many apple orchards on both the west and east sides of the state. These apples are commonly available in the early fall from August through October. However, these apples can be stored until about June using commercial practices (Colorado Apples). 

Other ingredients involved in the brewing process are gluten free yeast, water, sugar, hops and any additional flavors such as tannins, and acids. There are two main types of yeast, brewer’s yeast and baking yeast. For the hard cider brewing process it is important to use brewer’s yeast to get the best results. Specifically for STEM ciders who specialize in making 100% gluten free yeast it is important for them to be cautious when selecting their yeast. Most brewing yeast is a byproduct of the beer brewing process that involves barley and wheat making that brewer’s yeast not gluten free. Other alternatives is to use sugar beets to grow brewer’s yeast making it gluten free (Anderson). There are several yeast companies within the United States that will supply brewer’s yeast such as White Labs, and Bluebonnet Super Earth that are located domestically in California and North Carolina. The water that is involved in brewing is dependent on the location of where the cider is brewed. STEM ciders is located in Lafayette, Colorado which gets its water from snowmelt and treats it at Baseline Water Treatment Facility to distribute throughout the city (Public Works). The United States is the top producer of hops in the world behind Germany and the Czech Republic. The hops grows in mild climates that are found in the pacific northwest in the states of Washington, Oregon and Idaho (Chris). Hops need rich soil and mild temperatures as well as lots of water. Hops needs on average about 1.5 inches of water per week (Growing Hops). The last ingredient common to most ciders is sugar. The United States has one of the largest sugar industries in the world with most of our sugar coming from Florida, Louisiana and Texas (Abadam). It is likely that cider brewers get their sugar from these sources after they have been distributed across the United States and at local wholesale vendors. They are not likely getting it directly from the sugarcane farm. Overall, it is likely that all of the STEM ciders ingredients are sourced from places around the United States making the product more sustainably sourced than other products with more international ingredients. 

After the brewing process is done the cider is then canned and packaged for retail. STEM ciders use aluminum cans for the canning process. It is important to note that STEM ciders cans and packages their products in the same facility the cider is brewed. This removes the need for fuel for transportation during the manufacturing phase of the LCA. The cans are made through complex machining processes that combine alumina, “molten cryolite, a sodium aluminum fluoride mineral, to dissolve the alumina and separate the oxygen from it as direct electrical current (DC) is run through it, producing metallic aluminum and carbon dioxide gas (Chew)”. A more detailed description of the life-cycle assessment of aluminum cans can be found on the Design Life Cycle website. A link to this site can be found in the bibliography section of this paper. 

Once all of the cans are ready they are put into either four or six packs that are boxes made from paper cardboard. The two main countries that manufacture paper cardboard are China and the United States (Statista). These boxes are either created by mechanically or chemically grinding down wood into very small pieces (Top Cardboard). The United States being the second largest producer of cardboard in the world is likely to supply around the United States. Other materials that are associated with cardboard are the chemicals that are needed during the recycling process. These chemicals are whatever cleansing agents are necessary for cleaning any ink or other things off of the cardboard. There was a complete life-cycle assessment on cardboard conducted by Shayan Anoushiravani on the Design Life-Cycle website (Anoushiravani). 

The next step is the distribution of the packages of cider within the United States. This is most commonly done through using semi-trucks to ship large quantities at a time. According to the Phoenix Truck Driving Institute a semi on average gets about 6.5 miles per gallon (Semi-Truck). STEM ciders ship across the entire United States, into most states ranging from Los Angeles to up-state New York. This distribution process takes a lot of gas. To go the 1,000 miles from Denver to Los Angeles it takes about 154 gallons of gasoline and it would take about 231 to get to Buffalo, New York. One thing that could cut down the amount of fossil fuels that it takes to transport all of the products is if the cider company shares the semi-truck with other suppliers that are going to those same locations. This would ensure that truck loads are full and it would reduce the number of trucks that need to go to a destination. 

During the use and reuse phase of a can of hard cider there are no new raw materials introduced since this is a consumable product. The consumer simply needs to open the can and may consume as is. If they are inclined they may pour the beverage into a glass and drink it that way as well. 

During the recycling and waste management phase of the hard can of cider the only new materials that are introduced into the system are those already mentioned above with aluminum can and paperboard recycling. Since the hard apple cider is a consumable, there is no waste from this product if fully consumed. 

In summary for raw materials acquisition, though specific details about STEM Ciders' sourcing practices are unavailable, insights can be drawn from industry norms and geographical factors. Ingredients like apples sourced from top U.S. apple-producing states and gluten-free yeast from domestic suppliers contribute to the cider's environmental impact. Canning in aluminum and packaging in cardboard emphasize the need to understand material life cycles. Distributing products nationwide underscores the reliance on transportation, prompting efficiency considerations to reduce fossil fuel consumption. Using U.S.-based ingredients and packaging helps minimize the footprint of acquiring raw materials for cider brewing.

Embodied energy, a crucial component in assessing the environmental impact of products, reflects the total energy consumed throughout their lifecycle, from raw material extraction to manufacturing, transportation, use, and disposal. A comprehensive analysis of the embodied energy throughout the lifecycle of a can of hard apple cider offers valuable insights into the energy intensity of this popular beverage.

An important note for the specific energy values is that values are predicted for a functional unit of a 12 fluid ounce serving of hard apple cider unless otherwise specified. 

The lifecycle of hard apple cider begins with the cultivation of its primary ingredients: apples, yeast, hops, sugars and water. The agricultural phase of hard apple cider production encompasses several key activities, beginning with the establishment of the orchard. This includes the production of fruit seedlings at the tree nursery, soil cultivation, planting of trees, installation of a trellis system, and sowing of grass seed. Precipitation levels of 254 cubic meters per hectare (m3/ha) are assumed, eliminating the need for drip irrigation systems (Smith and Lal). The orchard transitions into the productive phase after three years, marked by continued soil cultivation, compost application, pesticide and fungicide application, mowing, harvesting, and transportation of the harvest to the cider production facility. Carbon dioxide uptake by biomass is estimated at 49 tons per hectare (t/ha), and annual compost application is estimated at 12 t/ha applied once annually each fall (Smith and Lal). Pest management includes various applications of dormant oil, Procidic, Sulfur, Surround, Entrust, DiPel, and Madex. Diesel needs for orchard maintenance, fertilizer, and pesticide applications are calculated based on tractor and trailer transport requirements. The average annual production is assumed to be 40.8 t/ha (Smith and Lal).

The threefour other major ingredients sourced for making hard apple cider, yeast, hops and water, are important for the system. Unfortunately, there was not enough information found on the energy consumption it takes to produce these ingredients outside of the fuel for transportation mentioned in the raw materials section of this report. 

Two other products that go into the LCA for hard apple cider are the aluminum cans the cider is packaged into and the paperboard boxes the cans are placed in for retail. The aluminum cans require material sourcing, casting and deformation energy for production which are 200-240 MJ/kg, 2.4-2.9 MJ/kg and 2.4-2.9 MJ/kg respectively (Ashby). The paperboard boxes require material sourcing and construction energy for production which are 24.2-32 MJ/kg and .0475-0.525 MJ/kg respectively (Ashby).

The embodied energy of cider production encompasses the energy required for processing equipment, water heating, fermentation, and packaging materials such as cans. The hard apple cider production phase begins with washing the apples, with water needs estimated at 757 liters per ton (l/t) (Smith and Lal). Apples are then crushed and pressed, with electricity needs estimated based on a vinification LCA study. The remaining cider undergoes UV pasteurization, with electricity requirements estimated at 0.22 joules per gram (J/g) of juice (Smith and Lal). Yeast is added for temperature-controlled fermentation, however, like wine, cider does not use heat in fermentation which cuts back on energy needed (Schuurman). Cider is then packaged in aluminum cans for distribution. Electricity requirements for packaging are estimated at 0.00108 kilowatt hours (kWh) per functional unit (Smith and Lal). The packaging energy also takes into account putting the cans into the paperboard cases used for retail. 

Another way to calculate the amount of energy consumption during the production phase is to estimate the amount of energy that it takes to run a cider brewery based on the expenses. It is estimated that an average single facility cider brewery in the United States costs about $1,000-$2,500 per month for utilities(Ryzhkov). These utilities pay for the electricity used on-site to run and operate all of the equipment used during the brewing process. Which on average is 16.19 cents per kWh which would mean between 61.8-154 kW of energy consumption per month (Ryzhkov). An important aspect of these costs is also where the energy is sourced from, which will lead to the cost per kWh. The source of energy in the case of STEM Ciders is the state of Colorado. According to the U.S. Energy Information Administration, the state of colorado has four main sources of energy generation, coal, natural gas, wind and solar. Coal generates 30% of Colorado’s energy, natural gas is 27.5%, wind is 25.6% and solar is 8% (“Electricity Data Browser.”) . The average cost of energy is different for residential and commercial land. Lafayette’s energy provider is Public Service Company of Colorado who charges 11.79 cents per kWh (Gelera). If the utility cost of STEM Cider’s brewery were known the amount of kiloWatt hours would be able to be derived knowing the 11.79 cents/kWh for electricity.

The distribution phase involves both on-site and off-site sales of hard apple cider. The scope of this report will only be analyzing off-site sales. Off-site distribution involves transporting packaged cans using lightweight commercial vehicles. This takes human energy to load commercial vehicles with the cases of hard apple cider. Another useful metric is the tonne-kilometer (tkm) which is used to calculate a payload distance. This is helpful when measuring the fuel energy required to distribute the product. It is 0.3 tkm for a full lightweight commercial vehicle (Smith).

The use phase of hard apple cider is very simple and includes just the energy required to keep the hard apple cider refrigerated if the consumer chooses to do so. Canned hard apple cider does not need to be refrigerated (Herrera). However, many consumers wish to refrigerate hard cider to be able to consume it cold. The typical consumer refrigerator is between 350-780 watts, the most common is 500 watts. These refrigerators tend to only actually use around 167 watts which is 122 kWh over the period of a month (Marsh). However, this energy consumption would be distributed over all of the other products the consumer has in the refrigerator at any given time. 

During the recycling and disposal phase of the hard cider there are two main processes that are taken into account, aluminum and paperboard recycling. The aluminum cans in which the hard apple cider is kept takes between 18 - 21 MJ/kg (Ashby). The paperboard boxes that the cans are packaged in for retail can also be recycled and takes between 18 - 20 MJ/kg (Ashby). 

To summarize the embodied energy, examining the embodied energy in the life cycle of hard apple cider reveals its complex energy dynamics from production to disposal. Energy inputs during orchard cultivation, processing, packaging, distribution, and recycling/disposal all contribute to its overall energy intensity. Off-site sales during distribution notably impact energy usage. While refrigeration may be needed during consumption, canned cider eliminates this requirement. Recycling aluminum and paperboard also incur energy costs. Addressing embodied energy is crucial for fostering sustainability in the hard apple cider industry.

Throughout the life cycle of a can of hard apple cider there are both sustainable and unsustainable waste processes that take place. From the cultivation of apples to the sourcing of packaging materials as well as the end of life recycling of materials, each phase contributes to the overall environmental footprint of hard apple cider. Notably, sustainable approaches are adopted in apple cultivation, ensuring the utilization of dropped and blemished apples that would otherwise go to waste, and the recycling of wastewater and materials back into the apple growing cycle showcases the sustainable approaches to hard apple cider. However, challenges arise with the transportation of ingredients and the final product, triggering carbon dioxide (CO2) emissions, primarily from medium-heavy-duty trucks. For this essay a functional unit or serving will be characterized as a 12 fluid ounce can of hard apple cider.

The waste generated during the raw materials acquisition phase of the Life Cycle Assessment (LCA) for hard apple cider encompasses various aspects. Firstly, in the cultivation of apples, a sustainable approach is employed where dropped and blemished apples, unfit for grocery stores or direct consumption, are still able to be used in the hard apple cider approach (Smith). Additionally, waste water and materials from apple cultivation are often recycled back into the cycle of growing apples, minimizing environmental impact(Smith). Secondly, the transportation of ingredients results in carbon dioxide (CO2) emissions. While no direct information was able to be found about the specific impact of shipping raw materials it can be assumed that ingredients were shipped on the standard medium-heavy duty trucks, accounting for approximately 23% of the transportation-related CO2 emissions according to the EPA's 2021 report(“Sources of Greenhouse..”). Thirdly, although direct information is lacking, it can be assumed that the apples, sugar, yeast and other ingredients are shipped to the processing facility using some sort of plastic shipping materials. This material would be discarded and either thrown away or recycled. Lastly, the sourcing of raw materials for packaging, including paperboard and aluminum cans, also incurs CO2 emissions, with paperboard sourcing emitting approximately 1.23-1.55 kg/kg and cans sourcing emitting approximately 11-13 kg/kg of CO2 (Ashby). Together, these waste and emissions factors showcase the importance of considering environmental impacts throughout the acquisition of the raw materials for hard apple cider.

In the raw materials acquisition phase of the LCA for hard apple cider, waste generation is effectively managed through various practices. Pomace, the residual pulp from crushed fruit, is repurposed and reintroduced into the system, serving as compost or livestock feed, with approximately 0.16 kg per a 12 oz serving of cider returned to the soil as organic carbon(Smith). Wastewater from the cider production process exhibits a high Chemical Oxygen Demand (COD) due to its elevated sugar and ethanol content, constituting approximately 10 percent of the cider volume produced (Joshi). Consequently, it requires treatment before discharge into the environment to mitigate its environmental impact. Additionally, in paperboard and can processing, carbon dioxide (CO2) emissions are generated, with paperboard processing emitting approximately 0.023-0.026 kg/kg of CO2, and can processing contributing to emissions through casting and deformation processes, with respective values ranging from 0.14-0.17 kg/kg and 0.19-0.23 kg/kg (Ashby). 

The transportation and distribution phase of hard apple cider is the most impactful phase of the LCA when it comes to waste. However, the amount of waste is directly related to the amount of product that is distributed on-site vs off-site. Cider producers that have 100% on-site distribution have much lower CO2 emissions than producers with off-site distribution. STEM Ciders has both on-site and off-site distribution so we will assume 50% and 50%, respectively. With this assumption it is estimated that on average there is 1.205 kg of CO2 emissions per serving of cider  (Smith). This could be lowered to 0.912 kg of CO2 emissions if the business model switched to 100% on-site distribution without any shipping  (Smith). An additional aspect for off-site distribution is the palette packaging to hold the cases of cider together in the trucks. Although direct information is lacking, it is reasonable to assume that plastic strips are used to secure the pallets containing cans of cider during transportation. These plastic strips, discarded upon arrival at the final destination, contribute to plastic waste.

During the use phase of hard apple cider LCA, proper waste management strategies are crucial to minimize environmental impact. The empty aluminum cans utilized for containing the cider can be recycled, as opposed to thrown away. Similarly, the cardboard boxes used to package the cider cans are also recyclable. Additionally, while refrigeration of the cider is common practice to maintain freshness, as stated in embodied energy, it is not necessary to refrigerate hard apple cider. The emissions associated with a fridge's operation make up approximately 4% of the average home's emissions, equating to roughly 82 kg of carbon dioxide (CO2) emissions per year (Alexander).

The waste from the recycling and disposal phase of hard apple cider is all from the mentioned aluminum cans and paperboard boxes that are waste products of the use phase. On average, aluminum recycling emits approximately 1.1-1.2 kg of CO2 per kilogram of material recycled(Ashby). Recycling cardboard/paperboard has CO2 emissions averaging around 0.72-0.78 kg per kilogram of cardboard recycled(Ashby). Although outside of the scope of the hard apple cider LCA it is important to note the recycling waste that is created during the recycling process of the aluminum cans as well as the paperboard boxes the cans come in. When remelting the aluminum to be re-casted there is generally a white layer of byproduct called white dross that forms at the top. This white dross contains 15-80 percent aluminum mixed with any impurities that were in the metal (“Aluminum Scrap…”). A waste byproduct of cardboard/paperboard recycling is something referred to as sludge that is formed when the ink and any other chemicals are soaked out of the cardboard when it is turned into pulp (Collins). 

In conclusion, the life cycle assessment (LCA) of a can of hard apple cider reveals a complex interplay between sustainable practices and environmental impact across the various phases. From the cultivation of apples to the sourcing of packaging materials, and even through the recycling and disposal phases, each step contributes to the overall environmental footprint of hard apple cider production. Noteworthy sustainable initiatives, such as repurposing dropped and bruised apples and recycling wastewater and materials back into the growing cycle, exemplify the industry's commitment to minimizing waste and optimizing resource utilization. However, challenges persist, particularly in transportation-related CO2 emissions and plastic waste from packaging materials. Moving forward, continued emphasis on waste reduction, recycling, and the adoption of sustainable practices throughout the cider production life cycle will be essential to mitigate environmental impact and foster a more sustainable future for the industry.

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