DemandEx™ is AI software that helps commercial solar buildings to increase demand charge savings. At a high level, DemandEx works by intelligently managing the most energy-intensive loads, typically HVAC, but also electric vehicle (EV) charging, energy storage, and other flexible loads.
There are two components to the DemandEx system. First, there’s off-the-shelf hardware that enables load controls and communications. More important is the cloud-based software that’s “the brains” behind the hardware. The following explains how the software and hardware work together.
How DemandEx Works - The Hardware
Before DemandEx can manage the building’s flexible loads, your solar contractor will install some off-the-shelf hardware. The DemandEx Gateway, the black box shown above, manages communication with the equipment in your building. While the gateway is “off-the-shelf,” it’s loaded with military-grade secure software that allows Extensible Energy’s cloud servers to communicate safely with your building and solar PV systems over your network. If the internet is intermittent, we can communicate through our dedicated cell connection as a backup.
In order for our AI software to issue commands and learn about the building’s energy usage patterns, we rely on the existing building management system (BMS) or smart thermostats. Most large commercial buildings have a central BMS that controls the HVAC and provides building data. When a BMS is present, we can connect our gateway using standard protocols (such as BACnet) and work with the BMS to provide the best possible combination of comfort and savings.
When a BMS is not present, DemandEx can use inexpensive smart thermostats to read the temperature, humidity, etc., and to control the HVAC system. We can connect to smart thermostats via Wi-Fi, Zigbee, and Z-Wave protocols. Having the option of all three of these standard protocols allows Extensible Energy to connect to and control buildings of every shape, size, and age.
One last source of data comes from installing a simple data logger (from eGauge, for example) that monitors the total energy usage of your building. evert minute, allowing DemandEx to adjust to variation in loads and verify that it is providing the estimated savings.
After the solar contractor installs our gateway and eGauge, and makes a secure connection to the BMS or thermostats, our cloud-based DemandEx software will be able to communicate to the building’s HVAC and other hardware, enabling DemandEx to relay commands and get real-time updates on the status of the building.
Your solar contractor can complete all work described here in less than one day. Now let’s explain how the software works.
How DemandEx Works – The Software
DemandEx’s overall goal is to save building owners and managers money on solar building’s electricity costs. The real value of DemandEx comes from its proprietary cloud-based software. The off-the-shelf building equipment is merely a communications portal.
DemandEx software has three main tasks: predicting, optimizing, and building controls. Keith Mosher, Extensible Energy’s Engineering Manager, describes the software as “an intelligent evaluation of how energy is being consumed and how energy can be moved to be consumed at a different time.” Many veteran solar and energy efficiency professionals commonly refer to this process as “load shifting” and “peak shaving.”
DemandEx predicts a hyperlocal weather forecast, solar output, and the building load for multiple time frames in the future. These forecasts are then given to a software model of the building that simulates what energy will be produced by the solar system and consumed by the building in the future.
Next, the building’s future simulations are passed to our optimizer, which determines what automated actions will result in the lowest overall energy cost. If any action is needed to prevent high energy costs, DemandEx’s software sends a command through the secure gateway to the building control layer, which is then relayed to the thermostats or BMS.
While DemandEx is excellent at forecasting the future, there will always be unexpected events. Because of weather variability, DemandEx is fully capable of making rapid response changes to the current building load. The long-term forecast will always eventually take priority over short term response. For example, if an electric vehicle is plugged in and about to set a new peak for the month, the software will turn off unnecessary flexible loads for a few minutes to avoid the peak.
That’s a quick summary of how DemandEx’s software and hardware work. Have more questions? Let’s set a time to talk.