HVAC: Using Vegetable Oil as a Dielectric, Renewable, and Sustainable Cooling Agent for Innovating Residential and Commercial Air Conditioning:

Concerns about the future availability and sustainability of traditional HVAC refrigerants have been increasing due to environmental regulations and the global push towards reducing greenhouse gas emissions. Here’s a breakdown of the issues:

Environmental Regulations:

Many traditional coolants used in HVAC systems, such as HCFCs (hydrochlorofluorocarbons) and HFCs (hydrofluorocarbons), have been found to contribute significantly to global warming and ozone depletion. As a result:

HCFCs: Have been phased out under the Montreal Protocol due to their ozone-depleting potential. 

HFCs: While not ozone-depleting, have a high global warming potential (GWP) and are being phased down under the Kigali Amendment to the Montreal Protocol and other regional regulations like those by the European Union and the United States’ AIM Act (American Innovation and Manufacturing Act).

Shift to Sustainable Alternatives:

The HVAC industry is shifting towards refrigerants with lower environmental impacts, including:

HFOs (Hydrofluoroolefins): These have much lower GWPs than HFCs and are being adopted as alternatives, though they are not entirely without environmental or toxicity concerns.

Natural Refrigerants: Such as CO2 (carbon dioxide), NH3 (ammonia), and hydrocarbons (like propane and isobutane), have low GWPs and ozone-depleting potential, making them more sustainable options. However, they come with their own set of challenges, including toxicity (ammonia), flammability (hydrocarbons), and high operating pressures (CO2).

Future of Traditional Coolants:

Given these trends, traditional coolants that are harmful to the environment are indeed at risk of becoming obsolete or unattainable due to:

Regulatory Bans and Phase-downs: Increasingly strict regulations are limiting the use of high-GWP refrigerants.

Market Pressure: As consumers and companies become more environmentally conscious, there is growing demand for HVAC systems that use sustainable refrigerants.

Innovation in Alternatives: Continued research and development in HVAC technologies and refrigerants are leading to more efficient and environmentally friendly alternatives.

Conclusion:

While traditional coolants face significant challenges and are likely to become less common in the future, the industry is adapting by developing and adopting more sustainable refrigerants and cooling methods. This transition supports global environmental goals but also necessitates new considerations for system design, safety, and efficiency. Homeowners and businesses considering new HVAC installations or replacements are increasingly likely to encounter systems using these newer, more sustainable refrigerants. This shift, while potentially costly in the short term due to the need for new equipment and possible regulatory compliance issues, ultimately benefits the environment and could lead to longer-term operational savings.

Using vegetable oil or natural ester-based dielectric fluids as a cooling medium in an HVAC (Heating, Ventilation, and Air Conditioning) system could offer an innovative, environmentally friendly alternative to traditional cooling methods. This approach could leverage the fluids’ thermal conductivity and dielectric properties, eliminating the need for fans and utilizing a renewable resource for cooling. Here’s a step-by-step guide on conceptualizing such a system:

Step 1: Selection of Cooling Fluid:

Choose an appropriate vegetable oil or natural ester-based fluid that has suitable thermal conductivity and heat capacity, is biodegradable, and has minimal environmental impact. The fluid should also be non-toxic and have a low viscosity to improve heat transfer efficiency.

Step 2: System Design:

Design a closed-loop cooling system where the dielectric fluid circulates through a series of pipes or channels. The system should include a heat exchanger component within the building to absorb heat from the indoor air and another component outside the building to dissipate the heat into the environment.

Incorporate a pump to circulate the dielectric fluid through the system. This pump replaces traditional fans used in air-based HVAC systems, providing the movement necessary for heat transfer without generating noise or requiring significant electrical power.

Design the indoor heat exchanger to maximize surface area for heat absorption. This could involve coils or plates through which the dielectric fluid flows, absorbing heat from the indoor environment.

Design the outdoor heat exchanger similarly, ensuring it is large enough to efficiently dissipate heat to the outdoor environment. This component might need to be more extensive due to the typically lower heat transfer efficiency to air.

Step 3: Integration with Renewable Energy Sources:

Connect the system to renewable energy sources such as solar panels or wind turbines to power the pump and any control systems, making the HVAC system more sustainable and reducing operational costs.

Step 4: Control System:

Implement a smart control system to monitor indoor temperatures and adjust the flow rate of the dielectric fluid accordingly. This system can optimize energy use and maintain comfortable indoor temperatures.

Step 5: Safety and Maintenance Protocols:

Develop safety protocols for handling and maintenance of the dielectric fluid, ensuring that it does not leak and is contained within the system.

Plan for regular maintenance to check the integrity of the system, clean the heat exchangers, and replace the dielectric fluid if necessary, based on its condition and performance.

Step 6: Testing and Optimization:

Build a prototype system for a controlled environment to test its cooling efficiency, energy consumption, and overall performance.

Optimize the system based on testing results, focusing on improving efficiency, reducing costs, and ensuring it can effectively maintain desired indoor temperatures under various conditions.

Step 7: Scale and Deployment:

Once optimized, scale the system design** for larger or different types of buildings, adapting the design as necessary to meet different cooling demands and architectural constraints.

Promote the environmental benefits of the system to encourage adoption, highlighting the use of renewable resources, reduced energy consumption, and potential for integration with renewable energy sources.

This approach represents a shift towards more sustainable and innovative cooling solutions, leveraging the unique properties of dielectric fluids and renewable resources. However, it would require significant research and development to address challenges such as the long-term stability and heat transfer efficiency of the chosen fluid, system costs, and the practicalities of installing and maintaining such a system in various buildings.

Using regular store-bought vegetable oil as a cooling medium in an HVAC system or similar cooling application does present some intriguing possibilities due to its availability, relatively low cost, and dielectric properties. However, there are several factors to consider that impact its viability:

Thermal Conductivity and Heat Capacity:

Vegetable oil has decent thermal conductivity and specific heat capacity, which are crucial for its effectiveness in absorbing and transferring heat. While not as efficient as some specialized cooling fluids, it could still be functional for applications where extreme cooling capabilities are not required.

Viscosity:

Vegetable oil’s viscosity is higher than water and most traditional cooling fluids. High viscosity can lead to reduced flow rates and increased energy consumption by pumps required to circulate the fluid. This could potentially reduce the overall efficiency of the cooling system.

Thermal Degradation:

Over time and with repeated heating and cooling cycles, vegetable oil can degrade. This degradation can lead to the formation of sludge and other by-products that could clog system components and reduce efficiency. The degradation rate would depend on the system’s operating temperatures and the specific type of vegetable oil used.

Chemical Stability:

Vegetable oils are biodegradable and environmentally friendly, but they can oxidize and become rancid over time, especially when exposed to air and high temperatures. Antioxidants and other stabilizers can be added to extend the oil’s life, but these additives may need to be carefully selected to maintain the fluid’s dielectric properties.

Flammability:

While vegetable oils have a higher flash point compared to many synthetic coolants and are generally considered less flammable, there is still a risk of fire if the oil is heated beyond its smoke point in the presence of oxygen. This risk must be managed, especially in systems operating at high temperatures.

### Compatibility with System Materials

The compatibility of vegetable oil with the materials used in the cooling system (such as metals, seals, and plastics) would need to be evaluated to prevent corrosion, degradation, or other forms of material failure over time.

In summary, while regular store-bought vegetable oil could potentially be used as a cooling medium, its effectiveness and efficiency would be limited by factors like thermal conductivity, viscosity, thermal degradation, and material compatibility. For a practical and efficient system, these challenges would need to be addressed, possibly requiring the modification of the oil or the system design. Further, the application would likely need to be non-critical and able to accommodate the lower cooling efficiency and higher maintenance requirements compared to systems using specialized cooling fluids.

If viscosity is issue, then you would simply overcompensate for a larger pump than needed to avoid wear and tear. Based on usage, the oil would have to be changed out, this would simply require a recurring maintenance agreement, baking soda is a natural deodorant and can assist in these measure, but frequently changing oil is best practice. This system could not be used for high temperatures but only for 65-75 Fahrenheit uses. 

Lets continue on with these parameters

Given the parameters and the acknowledgment of vegetable oil’s limitations and characteristics, we can conceptualize a cooling system designed for moderate temperature control, specifically aiming to maintain temperatures between 65°F to 75°F (approximately 18°C to 24°C). This scenario suggests a system that’s potentially suitable for certain residential or commercial environments where such temperature ranges are desirable. Here’s how you might proceed, incorporating your considerations:

Step 1: System Design and Component Selection:

Select a high-capacity pump to compensate for the high viscosity of vegetable oil, ensuring it can circulate the fluid effectively through the system without excessive wear and tear.

Design the system with wide pipes and channels to reduce resistance to oil flow due to its viscosity.

Incorporate a large heat exchanger both indoors and outdoors to maximize the heat transfer area, accommodating the lower thermal conductivity of vegetable oil compared to traditional cooling fluids.

Step 2: Maintenance Protocol Development:

Establish a regular maintenance schedule for changing the vegetable oil to prevent degradation and accumulation of by-products that could hinder system performance. The frequency of oil changes would depend on system usage patterns and could be optimized over time.

Incorporate filtration systems to remove particulates and degradation by-products from the oil, extending its usable life.

Consider using baking soda or similar natural deodorants in areas where oil is stored or in the maintenance process to manage odors, especially given vegetable oil’s tendency to oxidize and become rancid over time.

Step 3: Temperature Control and Efficiency Optimization:

Implement a smart control system that can adjust the flow rate of the vegetable oil and manage the operation of the pump and heat exchangers, maintaining the desired temperature range efficiently.

Optimize the system for energy efficiency, potentially incorporating variable speed drives for the pump to reduce energy consumption during lower demand periods.

Step 4: Integration with Renewable Energy:

Connect the system to renewable energy sources, such as solar panels, to power the pump and control systems, enhancing the overall sustainability of the cooling solution.

Step 5: Environmental and Safety Considerations:

Ensure safe operation by monitoring the temperature of the vegetable oil closely to prevent it from reaching its smoke point, thus avoiding potential fire hazards.

Plan for environmentally responsible disposal or recycling of used vegetable oil, considering options for repurposing or biodiesel production to minimize waste.

Step 6: Testing and Evaluation:

Build a prototype system for extensive testing in a controlled environment, evaluating its performance in maintaining the desired temperature range, energy efficiency, and overall operational stability.

Gather data and feedback to refine maintenance schedules, optimize system design, and improve performance based on real-world usage patterns.

Step 7: Scalability and Deployment:

Assess the scalability of the system for different building sizes and types, adjusting design parameters as necessary to meet diverse cooling needs.

Develop informational materials to educate potential users about the benefits, maintenance requirements, and environmental advantages of this innovative cooling solution.

By carefully addressing the unique properties of vegetable oil and designing the system with these considerations in mind, it’s possible to create a sustainable and effective cooling solution for specific applications. This approach emphasizes the importance of regular maintenance, energy efficiency, and environmental sustainability in modern HVAC system design.

Expanding on Step One, let’s delve into the specifics of using wide pipes and channels, and the design considerations for the indoor and outdoor heat exchangers in a system using vegetable oil as a cooling medium. This setup would be quite different from traditional HVAC systems with ductwork and air-based heat exchange.

Wide Pipes and Channels

Purpose: The high viscosity of vegetable oil compared to water or traditional HVAC fluids means it requires more force to move through narrow pipes. Using wider pipes reduces the resistance to flow, making it easier and more energy-efficient to circulate the oil.

Location and Installation: These pipes would be installed similarly to traditional water-based cooling systems. They do not have to be in every room or wall but should be strategically placed to efficiently transfer heat from the indoor environment to the outdoor heat exchanger. The piping could run alongside or potentially replace traditional ductwork, depending on the building’s layout and structural considerations. In most cases, the pipes would be hidden in walls, floors, or ceilings, similar to water pipes or electrical wiring, to maintain aesthetics and practical use of space.

Substitute for Duct-lines: In a system designed to use a liquid cooling medium like vegetable oil, the pipes indeed substitute for the air ducts found in conventional HVAC systems. The primary difference is that while ducts move air to and from different spaces for heating and cooling, the pipes in this system circulate vegetable oil to absorb and dissipate heat without directly affecting air movement.

Indoor and Outdoor Heat Exchangers

Indoor Heat Exchanger: This component acts similarly to the evaporator coil in a traditional air conditioner. It transfers heat from the indoor air to the vegetable oil circulating within the system. The indoor heat exchanger would need to be designed to maximize surface area contact between the air and the pipes containing the vegetable oil to efficiently absorb heat. This could be a series of coils or panels situated in a central location or distributed throughout the building, depending on the design.

Outdoor Heat Exchanger:Analogous to the condenser coil in a traditional air conditioner, the outdoor heat exchanger releases the heat absorbed from the indoor environment into the outdoor air. This component would likely be larger than its indoor counterpart due to the lower efficiency of air-to-liquid heat exchange. It might resemble a radiator or series of coils designed to maximize airflow and heat dissipation.

Not Simply Return Ductwork: Unlike return ducts in air-based systems that circulate air back to the HVAC unit for reconditioning, the outdoor heat exchanger in this system is solely for dissipating heat from the vegetable oil to the outside environment. There’s no “return” of the cooled medium in the sense of air systems; instead, the cooled vegetable oil is continuously circulated back through the system.

In summary, adopting wide pipes and specific heat exchangers for vegetable oil cooling proposes a significant departure from traditional air-based HVAC designs. This system focuses on transferring heat via a liquid medium, requiring a reimagining of how we traditionally cool (and potentially heat) spaces. Design considerations would significantly impact the system’s efficiency, including the choice of materials, the layout of the piping, and the integration of the system within existing or new buildings.

Alright, let’s simplify this!

Imagine your computer or game console gets really hot when it’s working hard, right? To stop it from overheating, you need to cool it down. Now, imagine we have a special liquid, kind of like the oil used for cooking but made to cool machines instead of fry food. This liquid doesn’t get electricity going through it (which is good, so it won’t short-circuit anything), and it’s pretty good at picking up heat from hot stuff and carrying it away.

Making the Liquid Move

To use this special oil to cool down a building, we need to move it around, taking the heat from inside the building and dumping it outside. We use a pump for this – think of it as the heart of the system, pumping the oil around like blood through veins.

Big Tubes, Not Small Ones

But there’s a catch. This oil is thicker than water – imagine honey or syrup. If we tried to push it through skinny pipes, it would move really slowly, and we’d need a super strong pump, which isn’t practical. So, we use big, wide pipes instead, which lets the oil flow easily without needing an extra-strong pump.

Inside the Building: Picking Up Heat

Inside the building, we have a setup (let’s call it an “indoor heat picker-upper”) where this oil flows through. As it passes by, it picks up heat from the room. This part is like when you blow on hot soup to cool it down, except here, the oil is ‘blowing’ on the hot air inside (except without the blowing part).

Outside the Building: Dropping Off Heat

Once the oil has picked up all this heat, it’s now warm. We pump it outside to another setup (the “outdoor heat dropper-offer”), which lets the heat go into the air outside. This part works a bit like when your hands are cold, and you warm them up by holding a warm mug. The mug (in this case, our oil) loses heat to your hands (or the air outside).

Repeat!

The oil, now cooler from dropping off the heat outside, comes back inside to pick up more heat, and the cycle goes on. This way, the inside of the building stays cool and comfy.

Why It’s Cool (Pun Intended)

This way of cooling a building is neat because we can use a liquid that’s safe for the environment and can be easily replaced. Plus, since we’re using a pump and big pipes, we don’t need to use fans to push air around, which can be noisy and less efficient.

So, in a nutshell, we’re making a super cool (literally) system to keep buildings cool using a special oil, big pipes, a pump, and some clever setups to pick up and drop off heat!

Pipes: Copper

Heat Exchanger: Titanium coated Copper

Evaporated Cooler: Rigid Media Pads

For your innovative cooling system that utilizes vegetable oil as a dielectric fluid and incorporates elements of evaporative cooling and subterranean heat dissipation, several additional components and considerations can further enhance its efficiency, sustainability, and overall performance. Let’s discuss a few key aspects:

1. Control System

An advanced control system is crucial for optimizing the performance and energy efficiency of the cooling system. This system can monitor temperatures, fluid flow rates, and environmental conditions to adjust the operation of pumps and fans, ensuring optimal cooling while minimizing energy use. Smart controls could also allow for remote monitoring and adjustments, providing ease of use and maintenance.

2. Filtration System

Given the use of vegetable oil, incorporating a filtration system to remove particulates and potential degradation products from the fluid will be essential to maintain system efficiency and prolong the life of the oil and components. Regular filtration can minimize the risk of clogs in the heat exchangers and ensure smooth operation.

3. Expansion Tank

As the system heats and cools, the volume of the vegetable oil will change. An expansion tank allows for these volume changes without causing pressure variations that could harm the system. It helps maintain a constant pressure within the cooling system, ensuring stability and reliability.

4. Energy Recovery Ventilator (ERV)

Incorporating an ERV can improve the system’s efficiency by recovering energy from the exhaust air to pre-cool (or pre-heat) incoming fresh air. This is especially useful in maintaining indoor air quality while minimizing the energy load on the cooling system.

5. Subterranean Heat Exchanger Installation Considerations

Placing the outdoor heat exchanger underground is a smart way to leverage the earth’s relatively stable temperature for more efficient heat dissipation. A few considerations for this setup include:

Depth and Soil Type: The effectiveness of underground cooling depends on how deep the exchanger is installed and the thermal conductivity of the surrounding soil. Consulting with a geothermal expert can help determine the optimal depth.

Waterproofing and Drainage: Ensuring the enclosure is waterproof and has adequate drainage will protect the system from moisture and flooding, which is vital for longevity and reliability.

Insulation: Insulating the pipes leading to and from the underground exchanger can minimize thermal loss and enhance efficiency.

Accessibility for Maintenance: Design the installation to allow easy access for inspection, maintenance, and potential repairs of the underground components.

6. Renewable Energy Integration

To further enhance the system’s sustainability, consider integrating renewable energy sources, such as solar panels or wind turbines, to power the pumps and control systems. This integration can significantly reduce operational costs and the environmental impact of the cooling system.

7. System Redundancy

Incorporating redundancy for critical components, such as the pump, can enhance system reliability. Having a backup in place ensures that the system continues to operate smoothly even if one part fails, providing peace of mind and continuous cooling.

By addressing these additional components and considerations, your cooling system can achieve greater efficiency, reliability, and user satisfaction, making it a truly innovative solution for sustainable cooling.

Designing an innovative cooling system for a 1500 sq ft home, leveraging vegetable oil as a dielectric fluid for cooling, integrating evaporative cooling, and considering the inclusion of ceiling fans for manual airflow, presents an interesting and unique approach to residential HVAC. Here’s an outline of the system structure, estimated material costs, and a comparison with traditional cooling systems:

System Structure and Needs

1. Vegetable Oil-Based Cooling System

   – **Pump**: To circulate vegetable oil through the system.

   – **Pipes**: Wide-diameter copper pipes for efficient oil flow and heat transfer.

   – **Indoor Heat Exchanger**: Copper or aluminum to absorb heat from indoor air.

   – **Outdoor Heat Exchanger**: Placed underground for efficient cooling, using copper or aluminum.

   – **Filtration System**: To maintain oil quality.

   – **Expansion Tank**: To accommodate volume changes in the oil.

   – **Control System**: Smart controls for optimal system operation.

2. Evaporative Cooling

   – **Evaporative Cooler Unit**: For pre-cooling air during dry conditions, possibly centralized or with key placement in areas prone to higher heat loads.

3. Airflow Management

   – **Ceiling Fans**: In each major room to enhance air circulation and evaporation cooling effects.

4. Renewable Energy Integration

   – **Solar Panels**: To power the pump and control systems, reducing operational costs and enhancing sustainability.

Rough Material Cost Estimate

Given the uniqueness of this system, estimating costs can be challenging without detailed market research, but we can offer a broad comparison:

– **Pump and Pipes**: Premium due to the choice of copper and the need for wider diameters. Approximately $3,000 – $5,000.

– **Heat Exchangers**: Custom designs, especially for underground placement, could range from $2,000 to $4,000.

– **Filtration System and Expansion Tank**: Approximately $500 – $1,000.

– **Evaporative Cooler**: Depending on the size and model, $600 – $2,000.

– **Ceiling Fans**: About $50 – $200 per fan, with a need for 4-6 fans, totaling $200 – $1,200.

– **Solar Panels**: Significant upfront cost, possibly $10,000 – $15,000 for a system sufficient to power the cooling system and other home needs.

– **Total Rough Estimate**: $16,300 – $28,200 for the initial setup, not including installation, which can vary widely by location and the specifics of the home.

Comparison with Modern Systems

– **Traditional HVAC System**: The installation of a new central air conditioner for a 1500 sq ft home typically costs between $3,500 and $7,500, depending on the unit’s efficiency and the home’s ductwork condition.

– **Heat Pump Systems**: For both heating and cooling, they might range from $5,000 to $10,000, including installation.

Cost Analysis

– **Initial Costs**: The proposed innovative system is likely more costly upfront than traditional systems, mainly due to the custom components like the underground heat exchanger and the integration of solar panels.

– **Operational Costs**: Lower over time, especially with solar panels offsetting electricity usage. The maintenance costs might be higher due to the system’s uniqueness.

Renewability and Efficiency: Offers significant long-term benefits in sustainability and potentially lower operational costs due to reduced reliance on grid electricity.

Conclusion

While the initial setup costs of this innovative cooling system are higher than those of traditional systems, the operational costs could be significantly lower, especially with solar energy integration. This system’s renewability and efficiency aspects make it an appealing long-term investment, especially for homeowners prioritizing sustainability and independence from the grid. However, it’s crucial to consider local climate conditions, the availability of maintenance services for such a unique system, and potential savings from reduced utility bills when evaluating the overall cost-effectiveness.

To compare the costs of implementing a traditional HVAC system versus the innovative vegetable oil-based cooling system (without solar panels) for a 1500 sq ft new construction home, we’ll look at both the initial (material) costs and the ongoing maintenance costs. This comparison provides a more comprehensive view of the financial implications over time.

Traditional HVAC System Costs

Initial Costs:

– **Installation**: On average, installing a central air conditioning system in a new construction can range from **$3,500 to $7,500**. This cost includes the unit itself and necessary ductwork. The lower end might cover a basic, less efficient system, while the higher end could include a more efficient, brand-name system.

Annual Maintenance:

– **Maintenance**: Annual maintenance checks typically range from **$75 to $200** per visit. Assuming quarterly maintenance to keep the system in top condition, the yearly cost could be **$300 to $800**.

Innovative Cooling System Costs

Initial Costs:

– **Cooling System Components**: Based on the revised rough estimate without solar panels, the initial setup cost ranges from **$6,300 to $13,200**. This includes the pump, pipes, indoor and outdoor heat exchangers, filtration system, expansion tank, evaporative cooler, and ceiling fans but excludes the cost of installation, which can vary.

Annual Maintenance:

– **Vegetable Oil Replacement and System Maintenance**: Assuming the vegetable oil needs to be replaced annually due to degradation and to ensure system efficiency, and considering the system might require specialized maintenance due to its unique components:

   – **Oil Replacement**: The cost will depend on the system’s oil capacity and the current price of the vegetable oil used. Let’s estimate a broad range of **$200 to $500** for oil replacement, considering both the oil cost and the labor for replacement.

   – **Maintenance Visits**: If specialized maintenance is more costly than traditional HVAC upkeep due to the system’s uniqueness, let’s estimate **$100 to $300** per visit. Quarterly maintenance would then range from **$400 to $1,200** yearly.

Comparison Summary

Initial Costs:

– **Traditional HVAC**: $3,500 – $7,500

– **Innovative System**: $6,300 – $13,200

#### Annual Maintenance Costs:

– **Traditional HVAC**: $300 – $800

– **Innovative System**: $600 – $1,700 (including oil replacement and potentially higher maintenance costs)

Analysis

– **Upfront Investment**: The innovative system requires a higher initial investment than a traditional HVAC system. This is due to the cost of specialized components like wide-diameter copper pipes, underground heat exchangers, and additional features like an evaporative cooler.

Ongoing Costs: The annual maintenance cost of the innovative system is potentially higher, mainly due to the need for annual oil replacement and possibly higher costs for specialized maintenance.

Considerations: While the innovative system might be more costly both upfront and in terms of maintenance, it offers benefits not captured purely in financial terms, such as potentially lower operational costs (if grid electricity prices are high), improved sustainability from using a renewable resource, and the unique ability to integrate with natural cooling methods.

Conclusion

For a homeowner focused on sustainability and innovative technology, the higher costs of the innovative system might be justified by the long-term benefits and environmental considerations. However, for those primarily concerned with upfront costs and traditional maintenance routines, a standard HVAC system might be more appealing. The decision would ultimately depend on personal priorities, including cost, environmental impact, and interest in pioneering new technologies in home cooling.

As Always, God Bless,

James Arthur Ferguson

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