Is cultured beef really that good for the environment?
Meat is responsible for more greenhouse gas (GHG) emissions than the entire transportation sector. If cultured meat is as good as it claims to be; it can lower emissions by up to 17%.
When I started researching for this paper, I was expecting to answer the question of how much better is cultured meat than conventional meat. But as I got further and further into research, I started to question whether cultured meat was the better alternative at all.
Conventional meat is responsible for tons of environmental damage. Whenever you hear about cultured meat, the biggest statement would be that it’s better for the environment. It was invented so that people can have meat that is not destructive to the environment. We are told that cultured meat has 7–45% lower energy use (only poultry has lower energy use) and 78–96% lower GHG emissions.
Cultured beef is the most developed and most promising concept in the cultured meat category. So this review will find how much of a difference cultured beef specifically will make in yearly GHG emissions.
For anyone who’s new,
Cultured meat is meat that is grown straight from muscle tissue instead of growing the entire animal. Conventional meat is the meat that you are used by raising the entire animal, then killing it.
Conventional meat is destructive because especially in mass production, it uses a lot of resources and emits a lot of greenhouses gases(18% of global GHG emissions).
For example, imagine you’re baking a cake. If you make it from scratch you will have to put tons of resources into it. Eggs, flour, sugar, salt, butter, etc. But if you bought an instant cake from the store and just added water, you will get the same result. Cake! Except one way to do it requires way less energy and resources. Instant cake may not taste exactly the same, but it doesn’t stop you from eating it and enjoying it.
Good as it claims?
Conventional meat production is having more of an effect than anyone expected. With 33% of global land use (globally, 34% of the GHG emissions related to livestock production are due to deforestation) and 18% of global GHG emissions, an alternative needs to take place fast! Cultured meat was invented to avoid environmental destruction but keeping the tasty animal meat that we are all used to. With 96% lower GHG emissions, 99% lower land use, and 45% lower energy use it is a dream. But there are few LCA(Life Cycle Assessments) so is it truly as sustainable as it claims (what about mass production?) and how much better than conventional meat is cultured meat really?
Best Cultured Meat Method
There are four main cultured meat methods. Yet the effect on the environment is drastically different.
Cultured- A
The method I most often refer to as Cultured- A is a hypothesized system presented by Tuomisto and Teixeira de Mattos (2011). Embryonic stem cells are grown in a cylindrical stirred tank bioreactor in a medium of cyanobacteria hydrolysate (as the main feed input). With an average emission footprint of 2.01 kg CO2e* per kg of cultured meat assuming no fertilizer was necessary and electricity generation uses the lowest Thai emissions (in the study Thai had the lowest emissions).
Cultured-B
Cultured-B is also by Tuomisto et al. (2014) and is about the same as Cultured-A except wheat and maize alternatives are considered in addition to cyanobacteria and a capillary bioreactor was selected. In this case, it included an energy input in maintaining growth temperature (37ºC) for cultured cells. With 3.67 kg CO2e per kg of cultured meat.
Cultured-C
Cultured-C gets more complicated. Cultured-C and D are by Mattick et al. (2015b). First, muscle stem cells go through five days of proliferation. They are then put in a bioreactor for 72 hours of cell differentiation and mass gain. Corn starch microcarrier beads provide a scaffold around which cells proliferate, and the process is assumed to take place within stirred-tank bioreactors. Energy is required for aeration, mixing, and temperature regulation during the culture phase. Finally, the bioreactors are cleaned between each culture batch by rinsing with sodium hydroxide and heating to 77.5°C. Resulting in 22.1 kg CO2, 0.062 CH4, and 0.0043 kg N2O per kg cultured meat.
Cultured-D
Cultured-D is similar to Cultured-C but here, lower cell densities are achieved at the end of the proliferation phase, no further biomass growth is achieved in the differentiation phase, and the biomanufacturing facility building size and energy footprint are treated as comparable to a pharmaceutical plant, rather than a brewery as in the default scenario. Resulting in 22.1 kg CO2, 0.062 kg CH4, and 0.0043 kg N2O per kg cultured meat.
Comparison
Table 1
(^What I wrote above is different from the picture because the study used the most optimistic scenario in this table but I used the average scenario.)
As you can see Cultured-A has the lowest CO2 emissions and lowest GWP. Since it was not possible to separate the greenhouse gases it is not a good method to base off of. Same for Cultured-B. Cultured-C has a relatively low CO2e* and all of its GHG statistics are available. Cultured-D has a very high CO2e* and a lot of methane and nitrous oxide. But the sensitivity of the analysis was high and the others are low. Does this mean that Cultured- D has true GHG emissions. If so, cultured beef is not a great alternative. Let’s assume that Culured-C is accurate for this article.
Global Warming Potential (GWP)
In Table 1, the CO2 emissions from cultured meat are far higher than conventional meat but the global warming potential is lower. How is this?
In the table, the global warming potential is calculated as the equivalent to CO2. The negative effect on the climate of methane is 23 times higher than the effect of CO2. Meaning 0.019 kg of methane is equal to 0.437 kg of CO2. The negative effect on the climate of nitrous oxide is 300 times higher than the effect of CO2. Meaning 0.0013 kg of methane is equal to 0.39 kg of CO2.
It would make the most sense to compare the CO2eq* because it considers everything.
Since most of the cultured meat emissions come from electricity, what effect does the energy have on the environment?
How much better is cultured meat?
Table 3
How sustainable will cultured meat be in 2050? In 2050 it is predicted to be a population 10 billion globally. Currently, people eat around 4 kg of beef per year so let's assume that will be the same in 30 years and everyone will eat 4 kg of beef every year.
(comparisons are not including emissions from deforestation)
Energy
Conventional meat
According to the Environmental impacts of cultured meat production in the UK to produce 1000 kg of beef you need 79 GJ of energy. 79 GJ has the CO2eq* of 7 tons when using coal (lignite) as an energy source.
280,000,000 tons of CO2eq* are emitted from the energy usage of conventional meat.
Cultured meat
According to Environmental Impacts of Cultured Meat Production, in order to produce 1000 kg of cultured beef, you need 33 GJ of energy which is equal to 3 tons of CO2eq*.
120,000,000 tons of CO2eq* are emitted from the energy usage of conventional meat.
Comparison
Compared to the greenhouse gas emissions from miles driven by an average passenger vehicle:
The conventional beef emissions are equal to 694,789,081,886 miles driven by an average passenger vehicle. The cultured beef emissions are equal to 297,766,749,380 miles driven by an average passenger vehicle. More equivalents
Conventional beef emits 160,000,000 more tons of CO2eq* than cultured beef.
According to my calculations, cultured beef energy emissions emit 95% more CO2eq than conventional meat. And requires 58% less GJ of energy.
Emissions
Conventional meat
According to Environmental impacts of cultured meat production, conventional beef production in the UK emits 45.1 tons of CO2eq* per 1000 kg of beef. If 10 billion people ate 4 kg of beef per year the GHG emissions from beef production every year would be 1,804,000,000 tons of CO2eq*.
Cultured meat
According to Environmental Impacts of Cultured Meat Production, cultured beef production in California emits 2.5 tons of CO2eq* per 1000 kg of beef. If 10 billion people ate 4 kg of beef per year the GHG emissions from beef production every year would be 100,000,000 tons of CO2eq*.
Comparison
Conventional beef emits 1,704,000,000 more tons of CO2 eq than cultured beef.
Cultured beef production emits 94% less GHG than conventional beef.
Compared to the greenhouse gas emissions from a number of passenger vehicles driven for one year:
Cultured beef production emissions are equal to 21,604,357 passenger vehicles driven for one year.
Conventional beef production is equal to 389,742,597 passenger vehicles driven for one year.
Overall CO2eq emissions comparison
(These calculations do not include deforestation emissions.)
In total conventional beef is responsible for 2,084,000,000 tons of CO2eq* per year. In 2012 the annual GHG emissions were 53 billion tons. So if we somehow managed to make the annual GHG emission 53 billion in 2015 (from trying to lower the emissions but not doing a good job because there's a lot of people) conventional beef production alone would make up for 4% of the global GHG emissions (not including emissions from deforestation).
But cultured beef would emit 220,000,000 tons of CO2eq* per year at a mass production rate (10 billion people eating 4kg of beef every year). This would make up for about 0.4% of global GHG emissions.
As far as GHG emissions go Environmental Impacts of Cultured Meat Production is pretty spot on. It says that cultured beef emits 96% less GHG and my calculation matches up pretty close to that (94%). Same for energy emissions. Environmental Impacts of Cultured Meat Production says that cultured beef requires 45% lower energy use and my calculations say 58%.
Where are these emissions coming from?
Conventional meat produces greenhouse gases in a lot of ways:
Cows walking, cows burping, deforestation, slaughterhouse, and/or factory.
But with cultured meat, you get rid of most of those factors and you are left with sources that require energy:
factory (lab). So what’s the process?
Conventional Beef
Conventional beef gets most of its GHG emission the cows themselves. Cows emit methane when they burp, walk, and basically live. Since cows cant digest grass properly they emit grass when they burp. When cows walk and stomp on the grass, that emits methane. And since the cows need a lot of space to graze that requires a lot of deforestation.
Cultured Beef Process:
Figure 1
(^The cyanobacteria biomass flows presented in Figure 1 are from laboratory scale production at the University of Amsterdam.)
Cyanobacteria cultivation
Cyanobacteria hydrosylate is used as an energy and nutrient source for the growth and proliferation* of the muscle cells. There are many different cyanobacteria the University of Amsterdam could have used. Anabaena sp. and Nostoc sp.* are nitrogen-fixing cyanobacterias but since they used a synthetic fertilizer (synthetic fertilizer can also be replaced by using nutrient-rich wastewater or organic fertilizers), the University probably used Arthrospira platensis and Arthrospira maxima (Spirulina)*. Both of which are not nitrogen-fixing.
Cyanobacteria biomass is assumed to be cultivated in an open pond (0.30 m deep) and harvested by using sedimentation and continuous vacuum belt filters. The energy requirements used for cultivation of cyanobacteria, harvesting, fertilizer production, and construction and maintenance of the facility are based on the data from Chisti (source 1, Table 3).
Table 2
Bioreactor
It is assumed that the bioreactor is made from stainless steel. Production of 1 kg stainless steel requires 30.6 MJ primary energy and emits 3.38 kg CO2-eq. The bioreactor weighs 93 kg and can be used for about 20 years. The creation of the cylinder stirred tank bioreactor alone is 2,845.8 MJ and emits 314.34 kg CO2 eq. But I’m not going to include this information in the comparison because I am not comparing how much energy it takes to build a slaughterhouse (hint: it would be a lot).
The production of cyanobacteria accounts for approximately 23% of total energy use and 28% of GHG emissions. Accounting for 72% of total energy use and 71% of total GHG emissions.
Is it the solution to climate change?
Though cultured meat is way more sustainable than conventional meat, it isn't the solution to climate change but its a step in the right direction. We would have way better luck in minimizing GHG emissions by finding an efficient renewable energy source and/ or improving a pre-existing one.
Conclusion
Cultured meat is obviously the better alternative and as far as emissions and energy use goes all the bold claims you see in cultured meat articles are accurate. Not only is cultured beef better for the environment it has a lot of potentials to be even better. As I have mentioned many times, the majority of cultured meat’s emissions come from energy use. Which is GREAT. If cultured meat labs used renewable energy sources this would nearly eliminate its GHG emissions making it so much more sustainable. Conventional meat doesn’t have the same luxury because a lot of its emissions come from the cows. Unless you stop the cows from burping or walk (which won’t work out) the system will forever be destructive to the environment.
Index**
Words with * mean that the definition of that word is in this index.
Cyanobacterias
Anabaena sp.: Anabaena is a nitrogen-fixing*, blue-green algae with beadlike or barrel-like cells and interspersed enlarged spores (heterocysts). It is found as plankton in shallow water and on moist soil. There are both solitary and colonial forms. Full Definition
Nostoc sp.; Nostoc is a blue-green algae with cells arranged in beadlike chains that are grouped together in a gelatin-like mass. Ranging from microscopic to walnut-sized. Nostoc may be found on soil and floating in quiet water. Reproduction is by fragmentation. It has the ability to fix nitrogen in specialized cells called heterocysts*. Full Definition
Arthrospira platensis; An edible blue-green algae that is high in protein.
Arthrospira maxima (Spirulina): A microscopic filamentous aquatic cyanobacterium.
CO2e(q) (Carbon Dioxide equivalent): 1kg of methane is equal to 23kg of CO2. 1kg of nitrous oxide is equal to 300kg of carbon dioxide. To calculate the CO2eq multiply the nitrous oxide by 300 and the methane by 23. Then add those numbers to the CO2.
Heterocysts: A large transparent thick-walled cell that is found in the filaments of some cyanobacteria and is the site of nitrogen fixation- Merriam-Webster.
LCA (Life Cycle Assessment): The impact a system has on the environment through its entire life. More About LCA
Nitrogen-fixing: Bacteria that combines with nitrogen from the air into something that plants can use. Full Definition
Proliferation: To grow or multiply by rapidly producing new tissue, parts, cells, or offspring.
Sedimentation: A machine that separates water snd bacteria.
Vacuum belt filter: A big machine that comes in different forms. It removes liquid from items.
