Heating And Cooling A Climate Simulator or EcoSphere
Tweet ThisHeating And Cooling A Climate Simulator or EcoSphere is not as simple as it may seem. The main flaw organizations have made with ecospheres is they make their buildings/systems like a glass house (greenhouse). The main issue each glass houses are heat retention and no cooling. Glass houses act like a lens focusing sunlight into the building. At night, there is no general exit of heat.
For more information on structure how the BioSphere Works, Click here
For more information how the Eco-System Works and is designed, Click here
For more information on this website and other projects, Click here
For information how the Thermo-Electric Device is used in CELSS, Click hee
When trying to solve the problem of heating/cooling in an ecosystem bottled up in a small volume, the hardest part is removing the heat from the system, not heating the system. That’s easy. The Earth gets all of its energy from the sun. It is always from one direction the earth sits in a giant freezer, called outer space. Observing how the sun and earth are related tells us how climate comes to be. Climate is not created from what is heated on the Earth by the Sun, but how the radiance of heat cooled. The picture below shows the Earth with the sun exposing a part of the surface at a time. The dark side of the Earth is letting energy go into space; hence, this is sometimes called irradiation.
A proposed way to simulate how the earth is heated and cooled is by enclosing a freezer around the bottled up ecosystem. This method is suggested by a very good friend of my named Gordon Eckhardt. One side of the bottled up ecosystem is exposed to light and heat. The diagram below shows a dormitory freezer used to cool a 1/2 inch plywood box. A 4 inch fan takes air from the freezer and blows it into the box. A return pipe moves cooler air back into the freezer. The box contains a 40 gallon glass fish tank where the top of the tank is sealed with a hermetically closed door. Cold air can move around all of the sides of the tank except the top. On top are two LEDs 28 watt lamps used to provide light and heat to plants in the bottled up ecosystem.
Here is what it looks like in real. You can see the LED lights on the top. They are colored purple. The pipes are 2 inch PVC pipes encased in an adhesive heating duct insulator. Underneath the table in the picture is a vacuum and air pressure pump to control the barometric pressure in the 40 gallon tank. On the ground is a PIC 18F4550 CPU controlling the heating, cooling, relative humidity, LED lights and barometric pressure. It is networked together through an RS232 mini network to the data collecting PC and to the controls CPU (Central Processing Unit). The CPU has a climate profile programmed in EEPROM for daily operations. The EEPROM can be changed for different climates throughout the world.
The picture below shows the top of the tank. Surrounded around the glass opening is more plywood sealing in the cold air.
The Climate Simulator is similar to the Earth
To take home the concept of how this Climate Simulator works, compare the two pictures below. The Climate Simulator is turned 90 degrees CCW to line with the Earth. Notice the small area the Earth is exposed which is similar in the Climate Simulator. The LED lights expose the same amount of area. It’s interested that is scales down to this.
Does this really work?
The real question is making a cooling system (outer space) that can imitate the daily swings of temperatures throughout the day. And in this case it can. See the data below. To start this experiment, we need to understand how climate is different in different parts of the world. When living close to the Sea, the daily temperature swings are a lot less than if you live inland. For instance, in California the temperature swings near the ocean are around 20 degrees F in a day. When you go more inland, it swings around 30 degrees F. When living in the mid-West in the US, you can get swings up to 60 degrees in one day.
For all practical purposes, I have decided to do a temperature swing of about 20 degrees per day because I live near the ocean and it is best to imitate what I am familiar with rather than start with something totally different. All tests are done in Celsius. This means I need to have a cooling system that can move the temperature of the 40 gallon tank about 10 degrees C in one day. Or ratio between the temperature swing and the number of hours of daylight, it gives us a 1 degree C/ hour change.
How is Temperature Controlled?
The CPU has an EEPROM that contains the schedule daily cycles of Relative Humidity, Sun Light Amount, Temperature, Seasonal Carbon Dioxide, Barometric Pressure and Dew Point Temperatures. This is what it takes to control the bottled up ecosphere. The temperature and controlled by a rudimentary PID loop. There’s nothing to it at all. The real challenge is controlling the Relative Humidity and the Dew Point. These relationships are related by log rhythmic functions. This makes controlling the Dew Point a bit of a challenge. The Dew Point is also related to the Barometric pressure and the temperature. Change the pressure, and the Dew Point changes. The PIC processors have an operating system to monitor all of the functions. All functions are updated every 15 minutes. The control period is relatively long.
Cooling Data/Tests
Below is a test of the cooling capacity of the freezer. It needs to be at least 2 degrees F per hour. The system provides about 3.5 degree F per hour. There is about a 30 minute delay before the temperature affects the 40 gallon fish tank.
| Time | Inside Temperature | Outside Temperature | Ambient Offset Temperature | Total Delta Cooling |
| Fan is Turned On Here | ||||
| 9:00 AM | 65.7 F | 67.5 F | - | - |
| 9:15 AM | 65.4 F | 67.6 F | +0.1 F | -0.3 F |
| 9:30 AM | 64.4 F | 67.6 F | +0.1 F | -1.3 F |
| 9:45 AM | 63.1 F | 68.0 F | +0.5 F | -2.6 F |
| 10:00 AM | 62.6 F | 68.2 F | +0.7 F | -3.1 F |
| Fan is Turned Off Here | ||||
| 10:15 AM | 62.2 F | 68.7 F | +1.2 F | -3.5 F |
| Heating Begins | ||||
| 10:30 AM | 62.4 F | 69.7 F | ||
| 10:45 AM | 63.9 F | 70.7 F | ||
If you consider the amount of heat or energy on the outside of the box, the total difference in temperature is 3.5 + 1.2. This equals 4.7 degrees F per hour change. However, this will change with different paths of ambient temperature changes.
Heating Data
It turns out that a 28 watt LED lamps are enough to heat the 40 gallon ecosystem for the day. Yes, there is a lot of heat generated from LEDs. The alternative is to use a 85 watt HID Sodium Vapor lamp. That has heated this tank 10 degrees C in one hour. That’s not good. Below is the data measuring the inside and outside ambient temperatures.
| Time | Inside Temperature | Outside Temperature | Ambient Offset Temperature | Total Delta Heating |
| 11:15 AM | 64.0 F | 70.7 F | - | - |
| 11:30 AM | 65.3 F | 71.4 F | +0.7 F | +1.3 F |
| 11:45 AM | 67.5 F | 72.7 F | +2.0 F | +3.5 F |
| 12:15 PM | 70.0 F | 73.9 F | +3.2 F | +6.0 F |
| 12:30 PM | 71.6 F | 75.9 F | +5.2 F | +7.4 F |
| 12:45 PM | 73.2 F | 77.4 F | +6.7 F | +9.2 F |
The actual temperature change inside the chamber is +9.2 degrees F. That is not really the amount of energy delivered by the LED lights. The outside temperature changed while the test is run. It increased by 6.7 degrees F. This means the LED lights increased the internal chamber by 9.2 – 6.7 degrees F. That equates to 2.5 degrees F per hour. This is within the specifications for a day. It’s amazing how only two 28 watt LEDs can heat up a 40 gallon fish tank.
Can the LED Lights be Cooled by the Freezer?
That last test is to see if the freezer can cool the LED lights. Below is a tables showing the freezer cooling the LED lights.
| Time | Inside Temperature | Outside Temperature | Ambient Offset Temperature | Total Delta Cooling |
| 5:30 PM | 73.8 F | 76.6 F | - | - |
| 5:45 PM | 74.5 F | 76.3 F | -0.3 | -1.3 F |
| 6:45 PM | 73.8 F | 75.9 F | -0.7 | 0.0 F |
| Fan Turned Off | ||||
| 8:00 PM | 76.6 F | 75.6 F | -1.0 | +2.8 F |
This is a strange interpretation. The total cooling is 0.0 F, but the total cooling increases the temperature by 2.8 degrees F. It has to be the kinetic energy in the garage.
Conclusion
The cooling and heating tests show that the freezer and LEDs work, but when tested when the ambient temperature is elevated, there is a heating problem. After observing this, it is best to cycle daily climate changes with the heat/light of the day. This will reduce the amount of energy to cool and heat the system. A series of tests needs to be done to calculate how to cool the chamber when the ambient kinetic energy is very high.
For more information how the Eco-System Works and is designed, Click here
For more information on this website and other projects, Click here