Measurement and Verification (M&V) has commonly been used to quantify energy consumption changes in energy efficiency projects. The challenge? How can one inexpensively deploy M&V devices, while also minimize staff time in creating usable data sets for energy-efficiency analysis? The industry’s adoption of the Internet of Things (IoT) highlights what’s to come.
IPMVP Framework Leverages Continuous Data Measurements
The International Performance Measurement and Verification Protocol (IPMVP) framework has been utilized to determine energy savings by comparing measured consumption or demand before and after implementation of an Energy Conservation Measure (ECM). The Efficiency Valuation Organization (EVO) has reorganized the IPMVP documents with their latest publication of the IPMVP Core Concepts in October 2016.
IPMVP describes four well-known options for determining energy savings:
- Option A – Retrofit-isolation: Key Parameter Measurement
- Option B – Retrofit-Isolation: All Parameter Measurement
- Option C – Whole Facility
- Option D – Calibrated Simulation
Key to many of these options is continuous data measurements, both before and after implementation of the ECM, that will be used to quantify energy savings. As illustrated in the IPMVP Core Concepts: Avoided Energy Consumption = Adjusted Baseline Energy - Reporting Period Measured Energy.
Energy Performance Contracts where payments are based on reductions in energy costs within a stated period can utilize adherent M&V plans defined by IPMVP.
M&V Enables Continuous Commissioning
Actual energy consumption can be determined using continuous measurements of main utility meters or submeters. For instance, electric submeters can be placed in remote locations of a facility to monitor energy consumption of implicated electric circuits or equipment. In an example application of Retrofit-Isolation, an electrical submeter can be used to measure electric power consumed by the application of a variable frequency drive (VFD) to critical HVAC equipment such as a chiller.
As is well known, HVAC represents one of the largest sources of electricity consumption in commercial buildings. Accordingly, energy efficiency efforts have increasingly targeted HVAC systems as potential areas of energy savings. Building performance and sustainability trends are driving interest towards HVAC systems.
Continuous commissioning formalizes the process of ensuring that HVAC systems run at peak performance levels. This ongoing process is designed to resolve operational problems, improve tenant comfort, and optimize energy use for existing buildings. Continuous commissioning can also significantly extend the useful life of HVAC equipment. More than electric submetering data is needed. For example, granular data obtained from the HVAC system can include the following:
- Chilled Water Loop – Flow Rate, Pressure Drop, Supply/Return Temp, Supply/Return Setpoint
- Condenser Water Loop – Flow Rate, Supply/Return Temp, Supply/Return Setpoint
- Chiller – Status, Loading, Compressor Motor Input, VFD Control Status, Efficiency
- Cooling Tower – Status, Fan VFD/Multi-Speed Control, Entering Air Wet/Dry Bulb Temp, Leaving Air Wet Bulb Temp, Makeup Water Temp, Range, Approach, Effectiveness
Capturing such granular HVAC data for M&V and continuous commissioning can be daunting. Part of the problem is the rigidity of the sensor data infrastructure of most buildings. Even if the building has a Building Automation System (BAS) installed, the BAS was originally designed to run HVAC control loops, not to capture an extensive sensor data set needed for subsequent M&V-driven analyses. In that context, modification of the BAS to accommodate M&V-driven analyses will require costly BAS modifications and lengthy implementation delays.
IoT Delivers the Solution to Inflexible BAS Infrastructures
IoT retrofits enable a low-cost mechanism for capturing needed M&V sensor data from a building. IoT retrofits have great applicability wherever the limits of the BAS functionality have been reached.
Wireless IoT retrofits obviate the need to extend a wired BAS network infrastructure, and eliminate the costs associated with painful BAS software upgrades. A network of wireless IoT nodes can coordinate the capture of needed measurement data from every remote part of the building. Wired networks require great expense to modify.
IoT takes a leap far beyond the functionality of data loggers. Every extra hour spent on-site is another hour of wasted productivity. IoT retrofits capture customized data sets in a building and stream the measurement data to the cloud for visualization in real-time. You need not worry about whether the data loggers are actually capturing needed measurement data as configured.
IoT-driven cloud visualizations enable interested personnel to confirm at all times that needed measurement data is being captured. At any point in time, the comprehensive catalog of time-stamped data samples have been organized and made available for ready M&V-driven analyses. Don’t waste another minute preparing your data for analysis.
The Future Trend – Energy-as-a-Service (EaaS)
IoT has already shifted the M&V landscape that previously relied on an inflexible BAS or antiquated data loggers. The real value of IoT, however, happens to coincide with the rise of EaaS providers and applications.
With EaaS, an outside service company can guarantee a building’s future energy costs. Having taken on the responsibility contractually, the service company would bear the responsibility for managing energy costs, optimizing the physical plant (e.g., continuous HVAC commissioning), leveraging renewables, etc. EaaS essentially shifts the burden to the service vendor. A billion dollar project example certainly appears to indicate a significant shift in trend.
Effectively, an EaaS service provider functions as a software Application Layer in the cloud. Each building in a portfolio contains sub-systems (i.e., legacy BAS, IoT Retrofit, etc.) that feeds real-time data to the EaaS Application Layer for M&V, commissioning, energy services, etc.
EaaS service providers will require increasing amounts of real-time data to maximize their internal efficiencies. Every incentive under the service contract will drive towards that conclusion.
As EaaS offerings increasingly transform the energy markets, flexible deployments of IoT retrofits will continue to scale with the increasing data demands. Real-time data will be required from all facilities, whether undergoing construction, newly commissioned, or decades old. We already know that you can’t manage what you can’t measure. IoT will deliver the data the EaaS market demands.
The current BAS market will also likely change. In this framework, BAS vendors operate as a sub-system of the EaaS service provider operating at the Application Layer. EaaS Application Layer services will therefore increasingly dictate the data needed from the lower layers of technology in the building. IoT retrofits already represent the fastest, lowest-cost means to deliver the crucial data needed to operate the EaaS model.
M&V provides a useful service of increasing importance in the new markets for energy efficiency. IoT will enable EaaS to scale quickly into the market. The energy landscape has changed the market more rapidly than many expected. New market trends reliant on asset digitization, new energy service offerings, and the ubiquitous nature of cloud-based software systems have brought new dynamics into the building marketplace. IoT was built for EaaS.