Understanding Cost per Ton of Cooling per Square Foot

When it comes to designing or maintaining a building’s HVAC system, one of the critical factors to consider is the cost per ton of cooling per square foot. This metric provides insight into the efficiency and economic viability of the cooling system. In this article, we will delve into what this metric means, how it is calculated, and its significance in various scenarios.

What is Cost per Ton of Cooling per Square Foot?

The cost per ton of cooling per square foot is a measure of the cost to cool one ton of air per square foot of the building’s floor area. It takes into account the energy consumption of the cooling system, the cost of electricity, and the size of the building. This metric is crucial for determining the overall efficiency and cost-effectiveness of the cooling system.

How is it Calculated?

Calculating the cost per ton of cooling per square foot involves several steps:

Determine the total cooling capacity required for the building in tons. This can be calculated by multiplying the square footage of the building by the cooling load per square foot, which varies depending on the climate and the type of building.
Calculate the energy consumption of the cooling system in kilowatt-hours (kWh). This can be found on the equipment’s Energy Guide label or by consulting the manufacturer’s specifications.
Obtain the cost of electricity in your area. This can be found on your utility bill or by contacting your local utility provider.
Divide the total energy consumption by the total cooling capacity to get the cost per ton of cooling per square foot.

For example, if a building requires 100 tons of cooling and the energy consumption is 1,000,000 kWh, and the cost of electricity is $0.12 per kWh, the cost per ton of cooling per square foot would be $120 (1,000,000 kWh / 100 tons = 10,000 kWh/ton; 10,000 kWh/ton $0.12/kWh = $1.20/kWh; $1.20/kWh 100 tons = $120).

Significance in Different Scenarios

The cost per ton of cooling per square foot is significant in various scenarios, including:

New Building Design

During the design phase of a new building, the cost per ton of cooling per square foot helps determine the most efficient and cost-effective cooling system. By comparing different options, architects and engineers can select a system that minimizes energy consumption and operating costs while meeting the building’s cooling requirements.

Renovation Projects

For renovation projects, understanding the cost per ton of cooling per square foot can help identify areas where energy efficiency can be improved. Upgrading to a more efficient cooling system can reduce energy consumption and lower operating costs over time.

Energy Audits

During energy audits, the cost per ton of cooling per square foot provides a benchmark for evaluating the efficiency of the existing cooling system. By comparing the current cost per ton to the industry average or to more efficient systems, energy auditors can recommend improvements to enhance energy efficiency.

Energy Savings

Reducing the cost per ton of cooling per square foot can lead to significant energy savings. By implementing energy-efficient cooling systems, buildings can reduce their carbon footprint and contribute to a more sustainable future.

Table: Cost per Ton of Cooling per Square Foot Comparison

Building Type	Cost per Ton of Cooling per Square Foot
Residential	$0.80 – $1.20
Commercial	$1.20 – $1.80
Industrial	$1.80 – $2.50

As shown in the table above, the cost per ton of cooling per square foot can vary significantly depending on the type of building. This highlights the importance of considering the specific needs and characteristics of each building when selecting a cooling system.