The evolution of building energy is moving toward more connectedness and control. The objectives of this purposeful evolution are lowering costs and carbon emissions, while maintaining or enhancing comfort, safety, and reliability. One innovation that will be key to achieving these objectives is IoT, or Internet of Things.
IoT in the context of buildings refers to a next generation of building controls and components that are connected to each other, and to external controls and monitoring. A key feature of IoT is the ability to automate outputs. Automation using IoT helps optimize the efficiency of building systems such as heating, cooling, air exchange, lighting, snow-melt, water use, and more.
How IoT Automates
IoT systems and components operate in enhanced feedback loops. Sensors gather data about heat, light, pressure, mechanical stress, noise, vibration, you name it. That data is transferred through wires or wirelessly to a controller. Before IoT, that control often comes from a straightforward PID-type control which attempts to maintain the output (such as indoor temperature) at a target value.
With IoT platforms, the control is more sophisticated, incorporating multiple inputs, outputs, and algorithms. The computing power and control is cloud-based. Algorithms make it possible to combine more inputs, and add more output flexibility than is the case with hard-wired frameworks using PID control. As a result, one can say that the system is “orchestrated” through the cloud.
Examples of IoT in Buildings
IoT can monitor and control features that we don’t think much about, but that can have a material effect on energy costs and CO2 emissions. For example, for buildings with large glass facades or south-facing windows, the control of window shade positions can make a big difference in energy use. Window shade positions, and louver angles can be tied to variables such as indoor temperature, room occupancy, time-of-day, day-of-week, time-of-year, and even current and incoming weather. By automating the control of light and solar heat gain, and radiative heat loss through glass, the building is more comfortable while using much less energy.
Another example of using IoT in a building is controlling the demand for power with a microcontroller. Let’s say that a large building has its utility power disrupted, and it switches over to back-up power, such as a traditional on-site generator or fuel cells. The amount of power produced may not be as high as is normally consumed through the grid. With an IoT platform, a microcontroller can reduce power to motors, pumps, irrigation systems, ventilation systems, etc. that are equipped with ECMs (Electronically Commutated Motors) and VFDs (Variable Frequency Drives), and cut off the power to non-critical (and less efficient) on/off components.
By reducing demand for power, the building reduces energy use, making available back-up fuel supplies last longer. Reducing demand also saves money on equipment costs, by reducing the size of the equipment that’s needed for back-up.
Other Benefts of IoT Platforms
IoT is useful in reducing maintenance and repair costs, as motors and pumps, for instance, can be monitored for on-time, heat and vibration. When a motor approaches its maximum “pitch count”, or begins to operate outside of its normal parameters, that motor can be fixed right away, swapped out right away, or added to a maintenance schedule so that it doesn’t create an unexpected shut-down at an inopportune time.
Furthermore, older equipment that continues to run within normal parameters can be kept in service, rather than doing the “safe” thing and taking it out of service early in order to avoid those unscheduled, and costly shut-downs.
Extra: Integrating IoT with BIM (Building Information Modeling)
BIM is the 3-D modeling of a building process using specialized software. This software makes the building process easier, by streamlining the information stream (e.g. system design, engineering changes, etc.) that’s created and used for building a building.
BIM software programs (or SaaS) give more flexibility to the process of building a building because information can be kept up-to-date in real time, and can quickly provide cost scenarios for different options. These programs can also help to reduce costs and implementation errors.
As an increasing part of large building structures and systems, IoT platforms and infrastructure need to be integrated with these software programs. As IoT continues to evolve, BIM needs to adapt and account for these changes. This is a challenge that will be made easier as dialog and partnerships evolve along with the underlying technology.
Resources: A further resource for IoT-related subjects is IoT Hub