July 17, 2020
Connected solutions in the real estate industry have been around for years. They have been reported to minimize energy consumption, add new capabilities, and provide superior tenant services. However, a high cost has so far hampered their mass adoption among commercial, industrial, and residential facilities.
Emerging affordable technologies and advancements in the Internet of Things (IoT) accelerate the automation process: they help drive down costs, improve energy efficiency in commercial buildings, support environment-friendly practices, and create superior occupant experiences.
How does IoT streamline energy efficiency improvement in commercial buildings, and why do IoT solutions for HVAC play a major role in their transformation?
According to a technology review issued by the US Department of Energy, the residential and commercial buildings sector accounts for about 74% of electricity use and 40% of all U.S. primary energy use.
Heating, ventilation, and air-conditioning (HVAC) systems are just a small part of the commercial building infrastructure. But it takes an enormous amount of energy to condition air and then distribute it throughout a building. As a result, HVAC systems are responsible for up to 60% of the total power consumption of the building.
This happens for a number of reasons:
As a result, commercial building owners have to deal with the consequences:
IoT helps the energy sector transform from a centralized system to a distributed, smart, and integrated energy system, which enables fast computations and efficient decision making.
Today, lower technology costs and the increasing availability of wireless technologies are making it easier than ever to cheaply obtain sensor readings for various HVAC components. On top of this, recent advancements in data storage and cloud computing allow building operators to access the multitude of HVAC data points, such as temperature, pressure, flow rate, and gas concentration.
Smart building HVAC controls help optimize the amount of conditioned (i.e., heated or cooled) air supplied throughout a building. Smart controls optimize airflow using data provided by CO2 levels, occupancy, temperature, humidity, duct static pressure, and air quality sensors, and modulate the amount of airflow in one area without starving or over ventilating another.
In the Pacific Northwest National Laboratory (PNNL) case, the institution equipped rooftop units (RTUs) with advanced controllers featuring a multi-speed fan, economizer, and ventilation controls. The evaluation found approximately 50% electricity savings for RTUs.
Most commercial buildings employ a multi-zone system, which makes it harder to optimize the use of conditioned air. There are two ways to perform such control:
The Adobe company has chosen the VAV-based approach to air conditioning and heating in their headquarters. The office was divided into so-called neighbourhoods: if any of them remains unoccupied for more than 15 minutes, the HVAC system in the neighbourhood automatically shuts down.
Adobe achieved a 65% reduction in energy consumption, despite a simultaneous increase in the number of their employees.
HVAC systems face leaks, blockages, and deterioration on a regular basis, which leads to natural degradation of the system over the time. To detect and prioritize faults early on, IoT-powered HVAC systems come equipped with automated Fault Detection and Diagnostics (FDD) functionality, that includes a combination of sensors and algorithms.
Modern FDDs can not only show that something has malfunctioned in an HVAC system, but also determine the exact problem and its cause.
For example, Microsoft had 2 million data points at its Main Campus at Redmond, Washington, which consists of 125 office buildings. The data produced was merged into a single output, which laid the groundwork for massive predictive maintenance. As a result, maintenance checks that used to take weeks could be done in a few minutes. Overall, Microsoft realized energy savings of about 10% per year. As a result, 48% of the detected faults were corrected within 60 seconds.
A typical deployment architecture includes the following elements:
These advanced controls can optimize HVAC consumption in unoccupied building zones, detect and diagnose faults, and reduce HVAC usage during times of peak energy demand.