MORE INFORMATION, QUESTIONS, SOURCES AND REFERENCES

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1 MORE INFORMATION, QUESTIONS, SOURCES AND REFERENCES Switzerland and recycling: an example to follow? The Swiss are very good recyclers in general and in particular, they are great at recycling aluminium. They were the world champions in 2010 and remain among the best in the world. Comparative recycling data show that Switzerland is only a few spots behind first place. Switzerland can be considered as a great example but not best in class. That said, these rankings are not the only way to determine a true champion because some countries use different collection methods as well as different calculation methods. Sources: OECD data used by Swissinfo.ch and Eurostat data

2 But even at an impressive 96%, figures released in 2015 by the European Container Glass Federation show Switzerland edged out by Denmark (98%) and Sweden (97%) in recycling glass. The story is similar for recycling aluminium beverage cans: 2012 data published by the European Aluminium Association reveal a handful of countries, such as Norway (96%), doing marginally better than Switzerland (92%). Does recycling aluminium save energy compared to producing new (or primary) aluminium? To determine if recycling aluminium really does provide energy savings, we must compare the energy necessary to recycle 1 kg of aluminium to the energy necessary to extract and produce the same quantity of aluminium (1 kg) from a primary source, bauxite in this case. According to the website alu.ch, they indicate that In terms of comparability, we generally recognize that recycling allows for 95% energy savings in terms of the energy necessary to extract primary aluminium. In this particular article ( it is not exactly clear what is included in the 95% (are we talking about electricity only or heat as well? does this number only include remelting or bauxite extraction and its transport as well?). It is therefore not so easy to verify this number. In order to evaluate the accurateness of this number, or at least to check its order of magnitude, we asked Quantis to verify this number using the well-known Life Cycle Assessment (LCA) database ecoinvent (the same database used to perform LCAs at Nespresso). Quantis found that the order of magnitude claimed on alu.ch is similar to the results obtained from their calculations. The production of aluminium requires electricity and heat, and the calculation using the ecoinvent database indicates that 98% less electricity is needed to produce a capsule from recycled aluminium compared to a capsule made of virgin material (bauxite in this case). The calculation also shows that only 51% less heat is necessary. After converting these energy sources into primary energy, the energy savings between primary and secondary aluminium is 88%. We estimate that the order of magnitude claimed by alu.ch is aligned with the numbers we calculated. More details on our calculations are provided below:

3 According to ecoinvent, we see that the electricity necessary for aluminium production is 15.6 kwh/kg of primary (virgin) aluminium and 0.3 kwh/ kg of secondary (recycled) aluminium (which equates to 98% less electricity). For heat, the reduction is not as significant: 18 MJ/kg of primary (virgin) aluminium and 8.8 MJ/kg of secondary (recycled) aluminium (a reduction of 51%). When we convert these quantities of energy to primary energy equivalents (in other words, we convert the different units of energy (kwh, MJ) into one unit in order to compare the total energy requirement), we reduce the total energy necessary from 123 MJ to 15 MJ of primary energy by selecting secondary aluminium over primary aluminium, which accounts for an 88% reduction. Quantis s key hypotheses: For the production of primary aluminium, the calculations include total energy consumption (electricity, diesel, fuel oil, heavy fuel oil, natural gas) from bauxite extraction through to the production of the primary aluminium ingot excluding transport energy. For the production of secondary aluminium, the electricity consumption, heavy fuel oil and natural gas for the recasting is considered including a yield of 1.03 kg of aluminium waste as input for 1 kg of secondary aluminium produced. Where are used Nespresso capsules recycled in Switzerland? After collection, the used capsules are transported to Moudon to the BAREC Group plant where the capsule and coffee grounds are separated. The aluminium is then remelted whereas the coffee grounds are transferred to the biogas plant where it is transformed into renewable energy. Greenwatt/Ecobroye Biogaz Plant

4 Can you recycle aluminium indefinitely / in its entirety? Aluminium can be recycled indefinitely in the sense that it does not lose any of its properties after recycling. However, due to the recycling, some of the aluminium is oxidized, especially when we recycle very small pieces. Thus, for 1 kg of aluminium waste that will be recycled, a little less than 1 kg of secondary (or recycled) aluminium is produced. This aspect is considered in the calculation of the number of capsules, knives or peelers that can be produced from recycled capsules. How do we generate energy as a result of capsule recycling? Energy is generated through the anaerobic digestion of coffee grounds. This procedure allows for the production of biogas from coffee grounds (mixed with other organic wastes) which can then be burned to produce energy. We can then either recuperate thermal energy only or we can burn this energy source in a cogeneration power plant and produce not only heat, but electricity as well. This is what is done at the Greenwatt power station in Henniez with the coffee grounds from used Nespresso capsules. The heat generated from the Greenwatt biogas power plant is then used by consumers, namely the Nestlé Waters bottling plant in Henniez. The electricity is sold to the Swiss grid and is then used by Swiss households and other energy consumers in the region.

5 As shown in this infographic (source: Nespresso Switzerland, Greenwatt and Quantis), it is interesting to point out a few key facts about the generation of energy at the Henniez biogas plant: Coffee grounds, while only representing 13% of the total volume used by the plant, accounts for 75% of the energy produced! In addition, the energy generated from the coffee grounds in one single used capsule is equivalent to the energy necessary to produce a single new capsule. Thus, the energy produced by the treatment of the coffee grounds allows for the Henniez biogas plant to save tonnes of CO 2-equivalent per year.

6 Difference between renewable and non-renewable natural gas When we speak of natural gas, we generally refer to fossil fuel, which is a hydrocarbon extracted from reservoirs beneath the surface of the earth as is the case for gasoline or coal, which release the carbon it contains to the atmosphere once it is burned. Natural gas is comprised mainly of methane (CH 4) but it also contains ethane, propane, butane and pentane. Like other fossil fuels, it is created by the sedimentation of organic matter over millions of years. Because this resource is still being created today, it could theoretically be considered to be renewable. However, the rate at which it is being consumed is extremely rapid compared to the millions of years necessary to form new fuels, and thus, it is classified as a non-renewable resource. The main countries producing fossil-based natural gas are the United States, Russia, Qatar, Iran and Canada. Biogas is a renewable energy source mainly composed of methane (CH 4) and carbon dioxide (CO 2) with small quantities of other gases (nitrogen, oxygen, water vapour) and occasionally small traces of other substances (e.g., hydrogen sulphide and ammonia). Biogas can be produced from organic matter by microorganisms through a process known as anaerobic digestion (thus no oxygen is present). A wide variety of organic wastes can be used for anaerobic digestion and thus be used to produce renewable biogas. Such wastes include household compost, agricultural wastes, food-processing industry wastes, sludge from wastewater treatment plants and wastewater. Because all of these organic materials are renewable, biogas produced as a result of their digestion is also a renewable energy source. There is currently huge potential to produce renewable biogases but it is currently underexploited for numerous reasons. The sources of organic wastes are not concentrated in specific locations but they are highly distributed, which means that biogas is a decentralized energy source that is available to all, while it largely remains underexploited. Sources: How can a recycled capsule provide energy to produce a new one and what does this include?

7 Coffee grounds can be used for the production of biogas. In turn, this biogas is used to produce energy. The quantity of energy is similar to the energy necessary to separate the capsule itself from the coffee grounds, transform the grounds into biogas, remelt the aluminium and finally form the new capsules (make thin aluminium sheets and form the capsules themselves). Constellium/Jean-Marc Hédoin Equivalence calculations The quantity of secondary (or recycled) aluminium obtained after recycling is calculated based on the quantity of aluminium for one capsule and the efficiency rate of the remelting process (85%). These data were measured by Nespresso. The number of new capsules, Victorinox Swiss Army knives or Zena peelers that can be produced from this quantity of secondary aluminium is calculated based on the mass necessary to produce one new capsule, one new knife scale (the aluminium part of the knife) or one Zena peeler handle (the aluminium part of the peeler). The quantity of coffee grounds from one single used capsule is based on the quantity of coffee contained in one 40-mL espresso capsule, from which we can remove the part that is extracted into the cup (15%) and by taking into consideration the humidity of the coffee after separation at the Moudon recycling plant (13%). All of these data were collected or measured by Nespresso. The quantities of heat and electricity that are produced as a result of the biogas generated from coffee grounds were calculated based on data from Greenwatt and Nespresso. The equivalences for the production of electricity are based on multiple sources: One LED lightbulb with a luminosity comparable to an incandescent 60-W bulb consumes 10 W according to A standard e-bike (electric bike) consumes an average of 1 kwh per 100 km according to the ecoinvent database (version 3.3) 11 Wh are required to charge a smartphone (considering an average between a Galaxy SIII and an iphone 5 which consume 12.3 Wh and 9.5 Wh, respectively according to cost-to-charge-an-iphone-5-a-thought-provokingly-modest-0-41year#methodology)