Tag Archives: Energy Efficiency

5 Energy Conservation Measures with Quick Returns

The Energy Cost Index (ECI) is the measurement of cost per square foot per year of conditioned space in a facility ($/ft²/year). The average ECI of electricity for an office building in the U.S. is about $1.73/ft²/yr according to the U.S. Energy Information Administration. What are you doing to reduce your ECI?

Continue reading 5 Energy Conservation Measures with Quick Returns  

Load Shedding and One Approach in CBAS

 

What is Load Shedding?As I’m sure you know, power companies charge a premium when a certain demand threshold is reached. Load shedding during high electrical demand periods is a good way to lower electrical consumption and avoid paying premium prices for exceeding peak demand limits. Metering or monitoring the load for the building will tell you when that threshold is nearing.

Load shedding will probably not work if the demand follows a bell curve during the day, where the threshold is exceeded for a good portion of the day. In this case, the building needs to find ways of increasing energy efficiency, either by purchasing more efficient equipment, eliminating waste, etc. However, if there is a peak in the demand curve that is exceeded around the same time everyday, load shedding could help. The question is, what can you afford to shut down without making people uncomfortable and angry? Continue reading Load Shedding and One Approach in CBAS

 

AHU Supply Temp Sets the Stage

In one of our recent articles, we discussed static pressure control and variable air volume (VAV) systems. We mentioned that by modulating the leaving air temp from an air handling unit (AHU) we can promote energy efficiency while also having an effect on static pressure. This time, we’ll look into how AHU supply temp sets the stage for efficient VAV operations.

Typically, VAVs are equipped with a means of reheating the supply air provided by the corresponding AHU. Continue reading AHU Supply Temp Sets the Stage

 

Static Pressure Control and VAV Operation

Static pressure is a key ingredient in a successful Variable Air Volume (VAV) system. It ensures that air flow will be available to enable the VAVs in a system to achieve their designed Cubic Feet per Minute (CFM) at maximum demand. Simply put, the push of the air must be greater than the resistance to the flow or no air will circulate through the ducts. Typically the setpoint for static pressure is determined through the course of the testing, adjusting, and balancing (TAB) at the end of a job. Continue reading Static Pressure Control and VAV Operation

 

Energy Analysis Solutions

Energy Analysis
Buildings rarely perform as initially intended, resulting in energy use that is higher than anticipated. To resolve this inherent problem, retro-commissioning, performance contracting, and facility IoT analytics have all emerged to capture market share. In practice, energy efficiency in buildings is achieved through the balanced combination of design concepts, applied technologies, and operational strategies. These work together to reduce the consumption of energy. Continue reading Energy Analysis Solutions

 

Cooling Tower Control Based on “Approach”

Cooling Tower Approach

By Mike Donlon
Director of Research and Development, Computrols

The most common Cooling Tower Control System uses a fixed temperature setting for the condenser water supplied back to the chillers. For convenience, let’s label this temperature:

TO = Tower Outlet temperature

To control this value, most controls technicians would program a control loop (PID or similar) to vary the overall Cooling Tower Fan usage in order to maintain this temperature. In most large buildings, multiple Cooling Tower Fans are available for this purpose. Continue reading Cooling Tower Control Based on “Approach”