Yesterday, I received a request from a environment and science reporter to comment as to which is better for the environment - real or artificial Christmas trees and I had 24 hours to respond. For once, I can empathize with people at Amazon fulfillment centers :-) Although I had not thought about this specific comparison, it being a perfect question for an LCA, I accepted the challenge of coming up with something interesting and overnight it.
At the outset, if someone feels they just want a real tree to get the real Christmas spirit, which no one argue with, then there is no need for further discussion. But say, one is interested in simply knowing the enviromental footprint of each. My plan is to hazard a calculated guess and my approach is to use as a spring board the paper versus plastic debate, which it feels like predates Christmas but is in the context of shopping bags or beverage/food containers.
Before jumping into the dry and boring mechanics of LCA, a first step is to see whether the two goods or products in question are functionally equivalent. If they are not, one needs to find a way to first make them comparable which in technical terms is called as System expansion or allocation. So needless to say we ought to be comparing two trees of identical dimensions and physical appearance.
Next, and right off the bat, there are no simple answers in an “overall” environmental sense, for what is “overall” is subjective. First, there are multiple different non-commensurate environmental burdens such as greenhouse gas emissions, criteria air pollutants, toxics, water pollution, and solid waste which have different impacts on human health and natural environment, and whose implications vary spatially and temporally. Next and on a related note, there are multiple different scarce natural resources consumed in the lifecycle of each including fossil fuel use, water use, land use. Finally, the sourcing of the natural resource (virgin vs recyled), the end-of-life management practices (reuse, composting, recyling, landfill or incineration) and how much transportation is involved at different stages of the lifecycle all matter to the calculus. That said, evidence suggests that in general plastic outperforms paper with respect of almost every measure other than biodegradability. So after round 1 of this match, it is even-steven.
Now, what are the differences and similarities to the paper vs plastic situation. Artificial christmas trees are made of plastic (of which there are many different types by the way and each can be produced from different types of fossil fuels) while wood from different types of trees is the main raw material for paper. So, in translating from paper vs plastic, we can drop the environmental impacts associated with converting wood to paper, which is the main reason that paper comes out poorer compared to plastic except with respect to biodegradability. This alone means that the balance might significantly be tilting towards natural trees. Round 2 goes to real trees.
Next, people often cite transportation as big potential waste of a resource but in my experience, it is unlikely to tilt the calculus one way or another even shipping stuff from a point diametrically across the globe. Round 3 is even-steven
Having said that, I need to point out a potential issue in the literature on LCA of plastics. Plastics are derived from an incidental co-product of oil refining, namely Naptha, which is cracked (broken down) to ethylene, the basic building block for poly-ethylene i.e. plastics. An aside, increasingly ethane that accompanies natural gas extraction is becoming the source of ethylene and this is also cleaner. In any case, the key word is incidental, which means the impacts of oil extraction, transportation and refining should be attributed to gasoline, diesel, jet fuel and heating oil which are the main reasons we drill for oil. Round 4 goes to artificial trees
The next critical aspect is reusability. In the paper vs plastic case, even though plastic bags can be reused, they rarely are while paper bags are either recycled or land filled. But artificial Christmas tress can last for years or decades and can be resold on craigslist and ebay while real trees tend to be discarded after one time use and tend to be landfilled or composted. My "guess" is if it is used for 5 times of so, the balance significantly tilts in favor of artificial trees. Round 5 - artificial trees big time and perhaps the knock out punch assuming they are reused multiple times.
This is the best my academic self can bring to say unambiguously without a full LCA. So, what should you do? As to what God wants from you, you know. For everything else, ask Alexa.
At the outset, if someone feels they just want a real tree to get the real Christmas spirit, which no one argue with, then there is no need for further discussion. But say, one is interested in simply knowing the enviromental footprint of each. My plan is to hazard a calculated guess and my approach is to use as a spring board the paper versus plastic debate, which it feels like predates Christmas but is in the context of shopping bags or beverage/food containers.
Before jumping into the dry and boring mechanics of LCA, a first step is to see whether the two goods or products in question are functionally equivalent. If they are not, one needs to find a way to first make them comparable which in technical terms is called as System expansion or allocation. So needless to say we ought to be comparing two trees of identical dimensions and physical appearance.
Next, and right off the bat, there are no simple answers in an “overall” environmental sense, for what is “overall” is subjective. First, there are multiple different non-commensurate environmental burdens such as greenhouse gas emissions, criteria air pollutants, toxics, water pollution, and solid waste which have different impacts on human health and natural environment, and whose implications vary spatially and temporally. Next and on a related note, there are multiple different scarce natural resources consumed in the lifecycle of each including fossil fuel use, water use, land use. Finally, the sourcing of the natural resource (virgin vs recyled), the end-of-life management practices (reuse, composting, recyling, landfill or incineration) and how much transportation is involved at different stages of the lifecycle all matter to the calculus. That said, evidence suggests that in general plastic outperforms paper with respect of almost every measure other than biodegradability. So after round 1 of this match, it is even-steven.
Now, what are the differences and similarities to the paper vs plastic situation. Artificial christmas trees are made of plastic (of which there are many different types by the way and each can be produced from different types of fossil fuels) while wood from different types of trees is the main raw material for paper. So, in translating from paper vs plastic, we can drop the environmental impacts associated with converting wood to paper, which is the main reason that paper comes out poorer compared to plastic except with respect to biodegradability. This alone means that the balance might significantly be tilting towards natural trees. Round 2 goes to real trees.
Next, people often cite transportation as big potential waste of a resource but in my experience, it is unlikely to tilt the calculus one way or another even shipping stuff from a point diametrically across the globe. Round 3 is even-steven
Having said that, I need to point out a potential issue in the literature on LCA of plastics. Plastics are derived from an incidental co-product of oil refining, namely Naptha, which is cracked (broken down) to ethylene, the basic building block for poly-ethylene i.e. plastics. An aside, increasingly ethane that accompanies natural gas extraction is becoming the source of ethylene and this is also cleaner. In any case, the key word is incidental, which means the impacts of oil extraction, transportation and refining should be attributed to gasoline, diesel, jet fuel and heating oil which are the main reasons we drill for oil. Round 4 goes to artificial trees
The next critical aspect is reusability. In the paper vs plastic case, even though plastic bags can be reused, they rarely are while paper bags are either recycled or land filled. But artificial Christmas tress can last for years or decades and can be resold on craigslist and ebay while real trees tend to be discarded after one time use and tend to be landfilled or composted. My "guess" is if it is used for 5 times of so, the balance significantly tilts in favor of artificial trees. Round 5 - artificial trees big time and perhaps the knock out punch assuming they are reused multiple times.
This is the best my academic self can bring to say unambiguously without a full LCA. So, what should you do? As to what God wants from you, you know. For everything else, ask Alexa.
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