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The Carbon Footprint of Cannabis: Unveiling the Environmental Impact of CO2 Extraction Equipment

CO2 extraction has become increasingly popular in the cannabis and hemp industries due to its reputation for being one of the safest and purest methods of extraction. This is largely due to the fact that CO2 is considered a clean and natural solvent that does not leave behind any harmful residues or contaminants. Unlike other solvents, such as butane or propane, CO2 is non-toxic and non-flammable, which makes it much safer for workers and the environment.


The content discussed in this conversation is not intended to condemn or criticize any CO2 equipment manufacturers or their products. CO2 extraction is widely considered to be a safe and efficient method of extracting cannabinoids from cannabis and hemp plants, and the engineering teams involved in the production of CO2 extraction equipment take safety precautions seriously.

However, we would like to bring attention to the potential environmental impact of unregulated and unchecked cannabis facilities that use high-pressure and high-volume CO2 extractors. The lack of federal regulations regarding the production and extraction of cannabis has created a grey area for oversight, and some facilities may not prioritize environmental compliance in their operations.

It is important for both equipment manufacturers and cannabis facilities to prioritize environmental responsibility and comply with applicable laws and regulations to ensure that their operations are sustainable and safe for the environment and surrounding communities.

Engineered Social Compliance

From a social compliance standpoint, CO2 extraction equipment is designed with safety in mind, incorporating closed-loop systems that prevent the release of solvents to the outside environment. This not only ensures operator safety but also helps to maintain compliance with environmental regulations. Additionally, the use of CO2 as a solvent allows for precise control over the extraction process, which helps to ensure consistent quality and purity of the final product.

Tunability of CO2 as a Solvent

Another advantage of CO2 extraction is its tunability, which allows for the extraction of specific compounds, such as THC or CBD, while leaving behind unwanted plant material. This is accomplished by adjusting the temperature and pressure of the CO2, which can be precisely controlled to achieve the desired outcome. This level of precision is not possible with other solvents, which can result in lower quality or impure extracts. As a result, CO2 extraction has become the preferred method for many cannabis and hemp producers who are looking to maintain high standards of quality and purity in their products.

Benefits of Various Solvents

I totally understand that the cannabis industry can be quite polarizing and contentious at times. With that being said, I want to make it clear that in discussing different extraction methods, I am not promoting one method over another. Each method has its own pros and cons and can be suitable for different applications and preferences.

Butane extraction can be efficient and cost-effective, but it also has a high potential for fire and explosion hazards. Ethanol extraction can be safe and effective, but it may also require additional post-processing steps to remove impurities. CO2 extraction is known for producing high-quality and pure extracts, but it can also be expensive and require complex equipment.

Ultimately, it is up to the individual user or facility to determine which method is best for their needs and goals. It is important to weigh the pros and cons of each method and to ensure that proper safety protocols and environmental compliance measures are in place.

Pros and cons for each extraction method:

Butane Extraction:

Pros of Butane:

  • High yields of THC and terpenes can be achieved

  • Butane is a relatively inexpensive solvent

  • The process can be relatively quick

Cons of Butane:

  • Butane is a highly flammable and volatile solvent, which poses a risk for explosions and fire hazards

  • Butane is not a clean solvent, and residual butane can be left in the final product if not purged properly

  • The process requires careful monitoring and skilled technicians to ensure safety and quality

Ethanol Extraction:

Pros of Ethanol:

  • Ethanol is a safe and effective solvent for cannabis extraction

  • The process is relatively inexpensive and can be scaled up easily

  • Ethanol is a natural solvent that does not leave harmful residues in the final product

Cons of Ethanol:

  • Ethanol extraction can also extract unwanted compounds like chlorophyll, which can affect the flavor and quality of the final product

  • The process can be time-consuming and requires careful temperature control

  • Ethanol can also be flammable if not handled properly, although it is generally considered to be safer than butane

CO2 Extraction:

Pros of CO2:

  • CO2 is a safe and clean solvent that is widely used in the food and pharmaceutical

  • The CO2 extraction process is highly tunable, providing precise control over the extraction process. This allows for targeting the cannabinoids at a molecular level, which is not possible with mass extraction methods like butane or ethanol

  • CO2 is non-toxic and leaves no harmful residues in the final product

Cons of CO2:

  • CO2 extraction equipment can be expensive and requires specialized training to operate

  • The process can be time-consuming and may not be as efficient in terms of yields as other methods

  • Large-scale CO2 extraction facilities can contribute to greenhouse gas emissions if not properly monitored and regulated

CO2’s Rise in Popularity

As the cannabis and hemp industries continue to grow, more and more companies are turning to CO2 extraction as a method of extracting cannabinoids and terpenes from the plant material. However, while many companies claim to use a "closed loop" system, the reality is that these systems can often be heard discharging large volumes of CO2 directly into the atmosphere.

Safety and Purity

While CO2 extraction is considered to be one of the safest and purest forms of extraction in the cannabis and hemp space, it's important to acknowledge the environmental impact of high-pressure, high-volume CO2 extractors. These machines require large amounts of CO2 gas to function, which can contribute to greenhouse gas emissions and climate change. Furthermore, if not properly designed or operated, these extractors can release large volumes of CO2 into the atmosphere, further exacerbating the environmental impact.

The use of CO2 in extraction has gained popularity due to its clean and natural properties, but it's important to recognize that it's not a perfect solution. While the engineering teams involved in the equipment's production do prioritize safety and environmental compliance, there is still work to be done in ensuring that these machines are designed with the utmost consideration for the environment. As the cannabis and hemp industries continue to grow and evolve, there is a responsibility to prioritize sustainability and reduce their carbon footprint.

Environmental Impact of CO2 Extraction

In order to address the environmental impact of CO2 extraction, it's important for regulatory bodies, equipment manufacturers, and cannabis facilities to work together towards a more sustainable solution. This can involve incorporating advanced monitoring and control systems, using renewable energy sources to power the equipment, implementing sustainable practices in cannabis cultivation, and exploring alternative solvents or extraction methods. By taking a holistic approach to sustainability, the cannabis and hemp industries can continue to thrive while minimizing their impact on the environment.

This is a serious problem, as CO2 is one of the main contributors to the greenhouse gas crisis that we are currently facing globally. While these systems do have reserve tanks for holding the used gas, many facilities choose to dump the spent gas directly into the atmosphere due to a lack of checks and balances, rather than recycling the gas supply.

Consider the environmental impact of a single 3500psi tank of CO2, which is being filled once or twice daily and dumped into the atmosphere over the course of a year. Now consider the fact that the average 40L cannabis system requires 3-5 100lb tanks of CO2. The numbers quickly add up, and the impact on the environment is significant.

Let’s look at the numbers:

To calculate the amount of CO2 being dumped into the atmosphere based on the information you provided, we can use the following formula:

CO2 dumped = (tank pressure x tank volume x number of tanks) / (gas constant x temperature)


  • Tank pressure is the pressure at which the CO2 is stored in the tank (in psi).

  • Tank volume is the volume of the tank (in L).

  • Number of tanks is the number of tanks being used (per day, week, or year).

  • Gas constant is a constant value of 0.08206 L x atm / (mol x K).

  • Temperature is the temperature at which the CO2 is being discharged (in Kelvin).

Using the average values you provided:

  • Tank pressure = 3500 psi

  • Tank volume = 40 L

  • Number of tanks = (assuming twice daily fills) 2 fills x 365 days = 730 tanks per year

  • Gas constant = 0.08206 L x atm / (mol x K)

  • Temperature = assumed to be 298 K (25°C)

Plugging these values into the formula, we get:

  • CO2 dumped = (3500 psi x 40 L x 730 tanks) / (0.08206 L x atm / (mol x K) x 298 K)

  • CO2 dumped = 1,394,748 mol

To convert the moles of CO2 to a more familiar unit, we can multiply by the molecular weight of CO2, which is 44.01 g/mol:

CO2 dumped = 61,355 g or 61.36 kg

Therefore, based on these assumptions, a 40L cannabis system using 3-5 100lb tanks could potentially dump approximately 61.36 kg of CO2 into the atmosphere per year.

Lack of Regulations at the Federal Level

When examining the data on CO2 emissions and their impact on the environment, it raises the question of which federal agencies are responsible for regulating and monitoring these emissions.

While regulatory agencies are responsible for safeguarding against issues related to manufacturing, it's possible that some issues may not be identified or addressed until they are brought to the attention of the agency or the public. It's also possible that some issues may be overlooked due to limited resources or a lack of awareness. In the case of CO2 extraction equipment in the cannabis and hemp industry, it's possible that the issue of CO2 emissions has not been widely recognized or addressed until more recently as the industry has grown and become more regulated.

Currently, many US states have legalized cannabis for medical or recreational use, and full hemp processing is also taking place. However, due to the federal government's stance on cannabis, this issue has gone largely unchecked and unnoticed. While there have been safety concerns raised about regulatory compliance in the cannabis industry, these have mainly focused on practices that would not be acceptable in other agricultural or pharmaceutical sectors. However, the issue of greenhouse gas (GHG) emissions from CO2 extraction in cannabinoid facilities has not received much attention.

It is important to note that the cannabis industry is still in its infancy, and regulatory agencies are just starting to catch up with the growing demand for safe and sustainable practices. The lack of federal oversight and clear guidelines on greenhouse gas emissions may be contributing to the problem. As more attention is paid to the environmental impact of cannabis production, it is likely that stricter regulations will be put in place to address this issue.

GHG Emission & Cannabis

Why has the issue of greenhouse gas emissions from CO2 extraction in cannabis facilities gone largely unnoticed or ignored? While these systems are marketed as "closed-loop," the reality is that once the system has been unpressurized, the gas that is 'reclaimed' into the ancillary storage tank is often released outside of the facility due to the presence of moisture, without adequate monitoring. This raises questions about the true closed-loop nature of these systems. Moreover, if the gas was truly captured, why do we see gas companies delivering large quantities of gas to these facilities on a weekly basis, without taking back an equal amount of contaminated CO2? This suggests that the majority of CO2 is lost to the atmosphere, contributing to harmful greenhouse gas emissions. While there are some teams that are aware of the negative impact of releasing GHG into the atmosphere and take appropriate measures, these instances are rare. Equipment manufacturers prioritize selling equipment over environmental concerns, and many teams may not fully understand the consequences of their actions. It is time for stricter regulations and greater oversight to be put in place to address this issue and ensure the cannabis industry operates in an environmentally responsible manner.

The process of recycling used CO2 gas involves purifying the contaminated CO2 by removing impurities such as water, oil, and other gases. Once purified, the CO2 is compressed and liquefied for reuse in a range of industrial and commercial applications.

Reclamation of Gas

It's worth noting that gas companies typically require cannabis or hemp CO2 facilities to purchase dedicated reclamation tanks to separate them from other tanks. This is to avoid any potential risk of exposing non-cannabis clients, such as soda machines at gas stations, to the contaminants often found in these tanks. So while it may appear that gas companies are swapping out tanks to recycle CO2, in reality, the tanks being loaded onto their trucks are often empty.

Accountability for GHG Crisis

As the use of CO2 in the cannabis industry continues to increase, it is crucial that equipment manufacturers are held accountable for the risks and exposure that contribute to the global greenhouse gas crisis. While companies may mention safety and closed-loop systems on their websites, it is essential for customers to do their due diligence and ensure that the equipment they purchase meets safety standards and is truly closed-loop. The responsibility of designing and manufacturing equipment that is safe and environmentally compliant falls on the companies, but the customers have the responsibility to use the equipment properly and follow all applicable laws and regulations. It is time for the industry as a whole to prioritize environmental responsibility and take meaningful steps towards reducing the negative impact of CO2 emissions.

The issue of corporate responsibility in relation to greenhouse gas emissions and environmental compliance is a complex one. While engineering firms have a responsibility to design and manufacture equipment that meets safety and environmental standards, they are not solely responsible for ensuring compliance or preventing CO2 losses. Regulatory bodies like the EPA also play a role in setting guidelines and regulations for equipment manufacturers and cannabis facilities to follow.

Engineering GHG Impact

It is important to note that engineering firms may prioritize factors such as efficiency, cost-effectiveness, and ease of use over environmental impact, which can lead to trade-offs in design and engineering decisions that impact the level of environmental compliance achievable. Additionally, not all firms may have the resources or expertise to incorporate advanced monitoring systems or technologies to prevent CO2 losses.

Therefore, it is crucial for cannabis facilities to work closely with equipment manufacturers and regulatory bodies to ensure that their equipment is designed and operated in an environmentally responsible manner. This involves incorporating monitoring and control systems, conducting regular maintenance and inspections, and implementing training and education programs for operators. Ultimately, it is a joint effort between equipment manufacturers, regulatory bodies, and cannabis facilities to address the issue of greenhouse gas emissions and environmental compliance in the industry.

It's time for the cannabis and hemp industries to take responsibility for their environmental impact. As consumers, we can demand that companies take steps to reduce their carbon footprint by using more sustainable extraction methods and properly recycling their gas supply. Let's work together to create a cleaner, greener future for the cannabis and hemp industries.

As we wrap up this discussion on the environmental impact of CO2 extraction equipment in the cannabis and hemp space, it is important to remember that CO2 is not just limited to extraction processes. CO2 is also heavily used in indoor grow rooms, which contributes to the carbon footprint of the cannabis industry as a whole.

In our next post, we will dive deeper into the carbon footprint of cannabis and how CO2 plays a role in indoor cultivation. We will explore ways to reduce carbon emissions and make the cannabis industry more sustainable.

We hope this discussion has shed some light on the importance of environmental responsibility in the cannabis industry, and we look forward to continuing the conversation.

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