Climate data from Al Kharj (KSA) and Al Ain (UAE) Problem: Pure Harvest is trying to design a greenhouse for each of the locations – Al Ain and Al Kharj. Using the dataset provided, please address the following questions. Please show your work on excel and provide the answers in a power point presentation.

QUESTION

Dataset: Climate data from Al Kharj (KSA) and Al Ain (UAE)
Problem: Pure Harvest is trying to design a greenhouse for each of the locations – Al Ain and Al Kharj. Using the dataset provided, please address the following questions. Please show your work on excel and provide the answers in a power point presentation.
Definitions:
• Enthalpy: Measurement of heat content in a system. Temperature and humidity can be used to calculate enthalpy in the air.
• Shortwave Radiation: Amount of energy that is transmitted through light radiation measured as Watts per square meter.
• Evaporative cooling: lowering temperature of a body of air by means of evaporating water. Incoming air needs to have low humidity (low water content). Resulting outgoing air has lower temperature and higher water content (net enthalpy remains the same).
• Mechanical cooling: lowering temperature of a body of air by means of energy transfer between the air and a chilled surface. Typically, that is done by passing air through a coil with chilled water and allowing for coil to come in contact with the air. Resulting outgoing air has lower temperature and lower water content (net enthalpy reduces).
Problems:
• Kindly identify the worst day of the year for each location – i.e. day with the highest temperature and highest relative humidity, day with lowest temperature and lowest relative humidity.
o Kindly identify the worst day in the past 5 years
o Kindly identify the worst day in the past 10 years
• For the rest of the questions, please only use data from the past 5 years.
• Please create a graph comparing monthly average temperature and humidity for each location.
o In your opinion, which of the two locations has higher year-round enthalpy?
• Kindly plot the hourly average summer day for a 24-hour period for each location. Kindly consider summer to be June-September.
o X-axis = hours 0-24 hours
o Y-axis = Shortwave radiation, temperature, relative humidity
• Assuming the farm in each geography is 10,000 sqm, and the structure allows for only 80% of shortwave radiation to enter into the farm (remaining 20% is refracted), for the average summer day:
o How much cooling do you require (in MWh) to remove all the energy entering the farm through light radiation in a 24-hour period during average summer day?
o How much cooling do you require (in MWh) to remove all the energy entering the farm through light radiation in a 24-hour period during the peak summer day?
o If you are using a 3MW chiller (mechanical cooling using chilled water) to cool the farm from light radiation, assuming no chilled water storage is available, at what points during the day will the chiller reach maximum capacity? Please mark the period of maximum loading on the average summer day 24-hour period graph.
o If you decide to use evaporative cooling to cool the farm, assuming you can only use evaporative cooling when relative humidity is under 40%, which period of the day will you be able to use evaporative cooling? Please mark the period of maximum loading on the average summer day 24-hour period graph.
Bonus questions:
• What do you think are the pros and cons between using mechanical cooling vs. evaporative cooling?
o Which of the two cooling systems would you give priority in each country?
• What are the pros and cons of using water-cooled and air-cooled chillers?
o Which of the two would you recommend using in each geography and why?

ANSWER

 Identifying the worst day of the year

For Al Ain (UAE):
Worst day in the past 5 years: [Date]
Worst day in the past 10 years: [Date]
For Al Kharj (KSA):
Worst day in the past 5 years: [Date]
Worst day in the past 10 years: [Date]

Graph comparing monthly average temperature and humidity for each location

[Insert the graph comparing monthly average temperature and humidity for Al Ain and Al Kharj]

In my opinion, based on the graph, the location with higher year-round enthalpy is [Al Ain/Al Kharj]. This is because it exhibits higher average temperatures and relative humidity throughout the year, indicating a higher heat content in the air.

Hourly average summer day for a 24-hour period:
[Insert the graph plotting shortwave radiation, temperature, and relative humidity for Al Ain and Al Kharj during a summer day from June to September]

Cooling requirements for the average summer day:
To remove all the energy entering the farm through light radiation in a 24-hour period during the average summer day, [calculate the cooling requirement in MWh] is required.
To remove all the energy entering the farm through light radiation in a 24-hour period during the peak summer day, [calculate the cooling requirement in MWh] is required.

Maximum capacity of the 3MW chiller:
The chiller will reach maximum capacity during [specify the period(s) of maximum loading on the average summer day 24-hour period graph].

Period for using evaporative cooling:
Evaporative cooling can be used when the relative humidity is under 40%. During the average summer day, the period for using evaporative cooling is [specify the period(s) of maximum loading on the average summer day 24-hour period graph].

Bonus Questions:

Pros and cons of mechanical cooling vs. evaporative cooling:
Pros of mechanical cooling:
Provides precise control over temperature.
Suitable for environments with high humidity.
Cons of mechanical cooling:
Higher energy consumption and costs.
Requires complex infrastructure and maintenance.
Pros of evaporative cooling:
Lower energy consumption and costs.
Natural and environmentally friendly.
Cons of evaporative cooling:
Limited effectiveness in high humidity areas.
Requires a constant supply of water.

In [country], I would give priority to [mechanical cooling/evaporative cooling] based on [reasoning].

Pros and cons of water-cooled and air-cooled chillers:
Pros of water-cooled chillers:
Higher energy efficiency.
Quieter operation.
Cons of water-cooled chillers:
Requires water supply and cooling towers.
Higher installation and maintenance costs.
Pros of air-cooled chillers:
Lower installation and maintenance costs.
No need for water supply or cooling towers.
Cons of air-cooled chillers:
Lower energy efficiency.
Louder operation.

Cooling requirements for the average summer day:
To remove all the energy entering the farm through light radiation in a 24-hour period during the average summer day, the cooling requirement is [calculate the cooling requirement in MWh].

Maximum capacity of the 3MW chiller:
The chiller will reach maximum capacity during [specify the period(s) of maximum loading on the average summer day 24-hour period graph].

Period for using evaporative cooling:
If evaporative cooling can only be used when the relative humidity is under 40%, the period during the average summer day when evaporative cooling can be utilized is [specify the period(s) of maximum loading on the average summer day 24-hour period graph].

Bonus Questions:

Pros and cons of mechanical cooling vs. evaporative cooling:
Pros of mechanical cooling:
Provides precise control over temperature.
Suitable for environments with high humidity.
Cons of mechanical cooling:
Higher energy consumption and costs.
Requires complex infrastructure and maintenance.
Pros of evaporative cooling:
Lower energy consumption and costs.
Natural and environmentally friendly.
Cons of evaporative cooling:
Limited effectiveness in high humidity areas.
Requires a constant supply of water.

In [country], I would give priority to [mechanical cooling/evaporative cooling] based on [reasoning].

Pros and cons of water-cooled and air-cooled chillers:
Pros of water-cooled chillers:
Higher energy efficiency.
Quieter operation.
Cons of water-cooled chillers:
Requires water supply and cooling towers.
Higher installation and maintenance costs.
Pros of air-cooled chillers:
Lower installation and maintenance costs.
No need for water supply or cooling towers.
Cons of air-cooled chillers:
Lower energy efficiency.
Louder operation.