Grid-Interactive, Efficient and Connected Buildings (GEBs)

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This section explores why the buildings need to be efficient, responsive, and able to interact with the electrical grid in a way that benefits both the building owner and the grid as a whole and what KPIs can be used to measure the effectiveness of the grid-connected buildings.


The respective parts of the document consist of the following:

  • The Benefits of Grid-Connected Responsive Buildings section identifies the community benefits
  • The GCEB describes the various features and technologies addressed in detail in the Grid-Interactive, Efficient and Connected Buildings Infrastructure section.
  • The KPI section identifies the criteria by which the performance of the GECB can be measured.
  • Finally Case studies section provides examples of the GECB implementation.

Benefits of Grid-Connected Responsive Buildings

The need for rapid decarbonization, feasible primarily through electrification, calls for grid-connected buildings. The potential benefits of grid-connected responsive buildings are :

  • Reduced peak demand: By shifting energy consumption to off-peak hours, grid-connected responsive buildings can help reduce peak demand on the electrical grid. This can help avoid power outages and prevent the need for new power plants to be built.
  • Improved grid reliability: Grid-connected responsive buildings can help make the grid more resilient and reliable. For example, they can provide backup power to the grid during periods of high demand or when there is a power outage.
  • Increased use of renewable energy: Grid-connected responsive buildings can help increase the use of renewable energy by optimizing energy usage when renewable energy sources are available.
  • Energy savings: Grid-connected responsive buildings can use real-time data and communication with the grid to optimize their energy consumption and reduce carbon emissions. For example, they can shift energy usage to off-peak hours when electricity is cheaper or reduce energy consumption during periods of high demand.
  • Cost savings: By optimizing energy usage and reducing peak demand, grid-connected responsive buildings can save money on energy bills. They may also be eligible for incentives or rebates from utilities for participating in grid programs.

Overall, grid-connected responsive buildings can help create a more sustainable, reliable, and cost-effective electrical grid, as well as provide greater resiliency and adaptability in the face of increasing disasters. An introduction of AI systems now expands the operational capabilities and even suggests the possibility of fully autonomously operated buildings connecting with and responding to the signals from the grid.

What are Grid-Interactive, Efficient and Connected Buildings

Grid-Interactive, Efficient, and Connected Buildings (referred to as GECB) are designed to optimize energy efficiency, interact with the electrical grid, and leverage smart technologies to enhance performance and sustainability. These buildings incorporate various features and technologies to reduce energy consumption, maximize the use of renewable energy sources, and enable two-way communication with the grid.[1] Buildings consume a lot of electricity, and more importantly, building energy use drives a comparable share of peak power demand. The electricity demand from buildings results from various electrical loads that serve the occupants’ needs. However, many of these loads are flexible to some degree. With proper communications and controls, loads can be managed to draw electricity at specific times and different levels while still meeting occupant productivity and comfort requirements.[2] At the same time, with the increase of on-site renewable and both stationary and mobile energy storage systems, the buildings can be, for some period of time, entirely grid independent or connected to a localized microgrid. Here are some key aspects of GECB:

  1. Grid Interactivity: GECB are designed to interact with the electrical grid dynamically and intelligently. They can adjust their energy usage based on grid conditions, pricing signals, and demand-response programs. By participating in demand-side management, these buildings can help stabilize the grid and reduce the need for additional power generation during peak periods.
  2. Renewable Energy Integration: GECB promotes integrating renewable energy sources such as solar panels, wind turbines, or geothermal systems. These buildings can generate their own electricity on-site and even feed excess energy back into the grid.
  3. Energy Storage and Management: GECB often incorporates energy storage systems such as batteries. These storage systems allow buildings to store excess energy for later use, especially from intermittent renewable sources. The stored energy can be utilized during periods of high demand or low renewable energy generation.
  4. Smart Building Management Systems: GECB utilizes advanced building management systems that integrate sensors, automation, and data analytics. These systems monitor and control various building parameters, including temperature, lighting, occupancy, and energy consumption. They optimize building operations and enable real-time energy efficiency and occupant comfort adjustments.
  5. Electric Vehicle Integration: GECB may include infrastructure to support electric vehicle (EV) charging. This facilitates the adoption of electric transportation by providing convenient and efficient charging options within the building premises.
  6. Microgrid integration: GECB may be integrated in a microgrid as a group of interconnected loads and distributed energy resources with defined electrical boundaries, which form a local electric power system able to operate in either grid-connected or island mode.
  7. Occupant Comfort and Well-being: GECB aim to provide enhanced comfort and well-being for occupants. They may incorporate features such as natural daylighting, indoor air quality monitoring, efficient ventilation, and occupant-responsive controls.
  8. Energy Efficiency: GECB prioritize energy efficiency through efficient HVAC (heating, ventilation, and air conditioning) systems, LED lighting, optimized building designs and advanced glazing and insulation. They aim to minimize energy wastage and reduce the overall demand for energy.
  9. Data Monitoring and Analysis: GECB generate vast amounts of data regarding energy consumption, grid interaction, and building performance. This data can be analyzed to identify further energy-saving opportunities, optimize operations, and inform future design and retrofitting decisions.

Integrating grid interactivity, energy efficiency, and connectivity in buildings helps create a more sustainable and resilient energy infrastructure. GECB play a vital role in supporting a clean energy transition and addressing the challenges of climate change and energy management.

ASHRAE “The Grid-Interactive Buildings for Decarbonization: Design and Operation Resource Guide” provides information on maximizing carbon reduction through buildings' interaction with the electric power grid. The guide offers best practices, design considerations and operational guidelines to target the three primary value streams of grid integration: Reduced Carbon Emissions, Cost Savings and Resiliency.

The Grid-Interactive, Efficient and Connected Buildings KPI’s

How do we evaluate the effectiveness of the Grid-Interactive, Efficient and Connected Buildings? The key KPI’s for the GECB are:

  • Reduced Peak Demand. (RPD %) is a key performance indicator (KPI) used to measure the effectiveness of energy management strategies in reducing the peak electricity demand of a building. It represents the amount by which the peak demand is reduced compared to the baseline or reference peak demand.

The RPD KPI is typically expressed as a percentage and calculated using the following formula: RPD (%) = [(Baseline Peak Demand - Actual Peak Demand) / Baseline Peak Demand] * 100 Here, the Baseline Peak Demand refers to the maximum electricity demand that would have occurred without implementing any energy management measures. The Actual Peak Demand is the maximum measured demand after implementing the energy-saving strategies. A higher RPD percentage indicates a more significant reduction in peak demand, which can have several benefits, such as:

  1. Cost savings: By reducing peak demand, organizations can avoid or reduce peak demand charges imposed by utilities, resulting in cost savings on electricity bills.
  2. Grid stability: Lowering peak demand helps alleviate strain on the electrical grid during times of high demand, reducing the risk of blackouts or brownouts.
  3. Environmental impact: Peak demand reduction can contribute to a more sustainable energy system by reducing the need for additional power generation capacity, which often relies on fossil fuels.

To track the RPD KPI, organizations typically monitor and analyze their energy consumption patterns, implement energy-efficient technologies, demand response strategies, load-shifting techniques, and other measures to reduce peak demand. Regular monitoring and analysis of energy data are crucial for evaluating the effectiveness of implemented strategies and identifying areas for further improvement.

  • Improved grid reliability can be measured through various key performance indicators (KPIs) that assess the quality and stability of the power supply. Here are some commonly used KPIs for evaluating grid reliability improvements:
  1. System Average Interruption Duration Index (SAIDI): SAIDI measures the average duration of power outages per customer. It indicates the average time in minutes that a customer experiences an interruption within a specified period, such as a year. A lower SAIDI value indicates improved reliability.
  2. System Average Interruption Frequency Index (SAIFI): SAIFI measures the average number of interruptions per customer within a specified period, typically a year. It represents the frequency of power outages per customer. A lower SAIFI value indicates improved reliability.
  3. Customer Average Interruption Duration Index (CAIDI): CAIDI calculates the average duration of power outages for customers who experience interruptions. It is obtained by dividing SAIDI by SAIFI. A lower CAIDI value indicates quicker restoration and improved reliability.
  4. Momentary Interruption Frequency Index (MIFI): MIFI measures the number of momentary interruptions or voltage dips per customer within a specified period. These are brief disturbances in power supply that last for a short duration. A lower MIFI value indicates improved reliability.
  5. Frequency and Duration of Voltage Deviations: This KPI assesses the frequency and duration of voltage variations or deviations from the standard power supply levels. It includes over- and under-voltages, which can affect the performance and longevity of electrical devices.
  6. Circuit Breaker Failure Rate: This KPI measures the failure rate of circuit breakers or protective devices responsible for isolating faulty sections and preventing widespread outages. A lower failure rate indicates improved reliability.
  7. Power Quality Events: Power quality events refer to disturbances like voltage sags, swells, harmonics, and flickers. Power quality events are typically measured using specialized instruments known as power quality analyzers or power quality meters. Monitoring the frequency and severity of these events provides insights into the stability and reliability of the grid.
  8. Customer Satisfaction Index: While not directly related to the technical aspects, customer satisfaction is an important measure of grid reliability. Surveys and feedback from customers can provide valuable insights into their perception of reliability and overall satisfaction with the power supply.

These KPIs can vary depending on the specific needs and regulations of a particular grid or utility company. Monitoring and improving these indicators help utilities identify areas for enhancement, plan maintenance activities, and prioritize investments to ensure a reliable power supply to customers.

Using the holistic H-KPI framework,[3] provides a more comprehensive view, enables aggregation and normalization of Grid-Interactive, Efficient, and Connected Buildings (GECB) indicators, and allows better quantification and comparison of different types of buildings, The H-KPIs use three levels: Level 1- technology, Level 2- infrastructure and level 3 – benefits. The interaction across the three levels of analysis is a central component of the H-KPI methodology. For example, sensors deployed at Level 1 inform the grid-connected building infrastructures at Level 2. The benefits of deploying the GECB are then manifested at level 3.

Reduced peak demandBenefits of Grid-Connected Responsive BuildingsNZEB RES Targets and Climate Response KPIsBenefits of Grid-Connected Responsive BuildingsWhat are Grid-Interactive, Efficient and Connected BuildingsMicrogrid Storage SystemNZEB RES Targets and Climate Response KPIsSmart Building IoT Infrastructure
Figure 1: Relationship of the three H-KPI levels of the Grid-Interactive, Efficient, and Connected Buildings ( In the web version clicking on the particular component of the diagram will take you to the relevant text section)

The Grid-Interactive, Efficient and Connected Buildings Infrastructure

Utilities

It is not just cities and buildings that are embracing Smart Technology to improve the services they provide; utility companies across the globe are also taking advantage of innovative technology solutions to provide better uninterrupted electrical supply networks. They are enhancing resiliency with a new generation of distributed energy resources – energy storage, micro-CHP, and even Non-Wire Induction Alternatives. This section will highlight recommended focus areas for utility companies that want to aid municipalities in becoming smarter.

At the basic level, electric utility companies can implement demand response programs where consumers are able to reduce or shift electrical usage during peak periods. Time-based rates and even financial incentives may reduce building owners' costs. Advanced smart meters can easily be installed and monitored along with facility generation equipment to reduce or eliminate the potential for downtime.

Different utilities may have different attitudes toward embracing grid-connected buildings. However, several factors may influence a utility's willingness to adopt connected building technology:

  1. Cost: The upfront cost of implementing connected building technology can be high, and some utilities may hesitate to invest in new infrastructure without a clear return on investment.
  2. Complexity: Connected building technology can be complex and may require significant changes to existing systems and processes. Utilities may be reluctant to take on this level of complexity without clear benefits.
  3. Regulatory issues: Regulations governing energy usage and data privacy can be complex and may vary by jurisdiction. Utilities may be hesitant to adopt connected building technology if they are uncertain about the regulatory landscape.
  4. Data management: Connected building technology generates large amounts of data, which can be difficult to manage and analyze. Utilities may be hesitant to adopt this technology if they are unsure how to effectively use and interpret the data.

That being said, many utilities are starting to embrace grid-connected building technology as a way to improve energy efficiency, reduce costs, and provide better services to their customers. As the technology continues to evolve and become more accessible, it is likely that more and more utilities will adopt grid-connected building technology.

Demand Dispatch and Smart Grids

In today’s traditional “supply dispatch” model, load and generation are balanced by equating load to consumer demand and dispatching power produced at central energy-generating plants to satisfy that demand. The “demand dispatch” model builds upon the supply dispatch approach by adding the support of “behind the meter” resources. Creating energy through onsite (renewable) generation is therefore important, but providing an electricity supply that saves on expanding new centralized power generation (plants) is equally important. Moreover, because renewable energy input can make power supply less predictable, it is increasingly important to find a way to balance power in the grid rapidly. Demand dispatch makes this possible by allowing for direct control of customer loads. Demand dispatch considers what load adjustments can be made before generation and whether those load adjustments improve grid optimization and are consistently dispatched as needed. Demand Dispatch can therefore help enhance reliability, peak load management, and energy efficiency, lowering the price of electricity.[4]

The demand dispatch approach to electricity supply requires Smart Grids and buildings capable of optimizing grid operations. Smart devices installed in buildings that directly interface with occupants and their demand for energy services are thus highly important. The relevant technologies in buildings, which enable demand dispatch, will be more obvious to occupants since they will change, to a certain extent, the perception of what to expect with an uninterrupted supply of electricity available at any moment.

As such, demand dispatch will require some form of behavioural adjustment by the consumers of electricity as expectations are shifted from supply dispatch to demand dispatch. For example, under the present supply dispatch approach, if a customer wants to start high-power demand appliances inside their home, such as a clothes dryer, it is expected that the machine will start as soon as they press the “on” button. Under the demand dispatch approach, however, if a customer pushes the “on” button, nothing would happen if there is no power capacity available to power their machine. Instead of the dryer starting immediately, their request for power would be put into an online demand queue. Then when the power can be allocated to them, the dryer would start.

Interconnected power-consuming equipment in our homes will have to play a significant role in supporting the transition to a demand dispatch model. Buildings that utilize smart technology will be integral in this process as well.

Smart Grids

How energy is generated and distributed significantly impacts how cities and municipalities can operate and the costs associated with their operation. With recent developments in grid technology, there are increasingly more ways in which utility companies and municipalities can improve a community’s ability to receive power and increase energy savings. Smart Grid refers to the capability of bidirectional information flow between the utility company infrastructure and the end user equipment. Smart Grids allow utility companies to manage their systems better, prepare for peak energy events, more quickly identify outage information, and help customers adjust their energy usage. Many advanced, effective metering and monitoring technologies are now available to building operators and/or utility companies.

Communication networks monitoring substation operations have made it possible to monitor critical infrastructure continually (and remotely), and now utility companies can provide alerts in a fraction of the time they have been able to in the past. Global Positioning System (GPS) combines network monitoring information with asset location information to pinpoint deficiencies in these systems and direct operations in real time. These operations are not limited to utility companies. Critical infrastructure within municipal buildings and campuses can be monitored in the same way. Building generation, backup fuel supply, Uninterruptible Power Supply (UPS), and heating, ventilation and air conditioning (HVAC) operations are all standard devices that can and should be monitored to improve efficiencies, help reduce energy costs, and lower overall operation downtime. Advanced Metering Infrastructure (AMI) and Automatic Meter Reading (AMR) are two technological solutions.

Advanced Metering Infrastructure (AMI) technology exists in millions of smart meters. These meters provide utility companies and customers with energy usage data that they can tie into their energy management systems and use to assist with budgeting. Building operators can shift their high energy usage operations to off-peak hours and, in many cases, take advantage of off-peak pricing to reduce costs.

Automatic Meter Reading (AMR) technology allows meters to be read with up to 100% accuracy without customer intervention. Rather than having utility companies enter a home or business to read meters, the job can now be completed remotely via wireless networks deployed throughout communities. AMI is also being leveraged for behavioral programs that engage customers and personalize their energy utilization. With today’s “smart” speaker devices, AMI is opening up a new way for customers to control and automate their homes with connected lighting and occupancy-based controls. Smart Grid technology may also facilitate individualized control of energy use and distribution through transactive energy.

Real-time Monitoring and Supervision KPIs:

Following are some of the KPIs which can be used to evaluate the efficiency of real-time monitoring systems: Absolute Grid Support Coefficient (-): Evaluate the grid impact of a building or its heating system. Building Operational Performance (%): Illustrates the performance of the building by relating the energy consumption, emissions, and geometrical information. Reduction of energy price by ICT-related technologies (%): Measures the price of the energy traded by an aggregator, both with baseline and after ICT implementation. Increased reliability (%) Grid Interaction Index (%): Describes the average grid stress, using the standard deviation of the grid interaction over a period of a year

Transactive Grid

The main difference between a Smart Grid and a transactive grid lies in their primary objectives and focus areas. While a Smart Grid primarily focuses on optimizing grid infrastructure and improving operational efficiency, a transactive grid emphasizes decentralized energy transactions and empowering consumers to actively participate in the energy market.

Some consider Transactive Grid to be the future of grid operations. Transactive energy is defined by the National Institute of Standards and Technology (NIST) as “a system of economic and control mechanisms that allows the dynamic balance of supply and demand across the entire electrical infrastructure using value as a key operational parameter.” To enable Transactive Grid, Utilities are developing Distributed Energy Platforms (DSP), that provide location-based grid services compensation for distributed energy resources and dynamic demand management. Such platforms utilize “blockchain technology” [5] to manage transactions on the sale and purchase of energy resources. Distributed Energy Platforms (DSP), also known as a Distributed Energy Resource Management System (DERMS) or Distributed Energy Management System (DEMS), is a technological framework that enables the integration and management of various Distributed Energy Resources (DERs) within an electric power system. A Distributed Energy Resource (DER) refers to any small-scale, decentralized power generation or storage device, such as solar panels, wind turbines, energy storage systems (batteries), or electric vehicles (EVs). These resources are typically located close to the point of consumption or within distribution networks.

A Distributed Energy Platform acts as a central management system that allows for the coordination and optimization of these Distributed Energy Resources. It provides a suite of software applications, communication protocols, and control mechanisms to monitor, control, and optimize the operation of DERs in real-time. The key functions of a Distributed Energy Platform include:

  1. Aggregation: It enables the aggregation of multiple DERs, irrespective of their location or type, into a virtual power plant (VPP) or a unified energy portfolio.
  2. Control and Optimization: It facilitates the monitoring and control of DERs, allowing for real-time adjustments to their generation, consumption, or storage based on grid conditions, energy demand, and market signals. Optimization algorithms help maximize the efficiency and economic benefits of DER operations.
  3. Grid Integration: It ensures seamless integration of DERs with the larger electric grid by managing the flow of electricity, voltage regulation, and maintaining grid stability.
  4. Demand Response: It enables demand response programs by dynamically adjusting electricity consumption or generation from DERs in response to price signals or grid conditions.
  5. Energy Market Participation: It allows DERs to participate in energy markets, such as wholesale electricity markets or local energy trading platforms, by providing bidirectional communication and data exchange capabilities. It would allow customers to market energy generated to other customers on the distribution system. This would reduce power and optimize consumption and service level impacts by allowing for automatic and more rapid adjustment of building services (e.g. cooling, heating, lighting, etc.).
  6. Data Management and Analytics: It collects and analyzes data from DERs to provide insights into energy consumption patterns, performance monitoring, predictive maintenance, and forecasting.

By leveraging a Distributed Energy Platform, utilities, grid operators, and energy service providers can efficiently manage and optimize the increasingly complex and diverse mix of DERs. It supports the integration of renewable energy sources, enhances grid reliability, enables demand flexibility, and facilitates the transition to a more decentralized and sustainable energy system.

Transactive energy support DER systems and buildings with active control technologies, even those connected to a microgrid. That said, significant challenges arise with greater interoperability. Because transactive energy creates an environment that fosters distributed, decentralized energy nodes controlled by a vast number of people on the demand side, a significantly more complex network of controls is created. Regulating and maintaining such a complex network can prove to be a difficult task.

Regardless of the challenges, the Pacific Northwest Smart Grid Demonstration Project provides a great example of the possible benefits of Smart Grids and transactive energy in practice. The project deployed 55 technologies in various communities across the Pacific Northwest, testing solutions including smart meters, battery storage, voltage controls, and transactive controls. In one study area, a utility company used transactive signals representing the current and near-future availability and predicted power price. They updated and sent the transactive signals out every five minutes. The project’s Smart Grid technologies were designed so that power use would decline when transactive signals predicted peak power demand and high costs. When the project team ran models simulating extreme events, such as a surge in wind energy and a nuclear power plant outage, the transactive controls worked accordingly. Their study shows that transactive energy provides viable electricity supply solutions during critical times and can lower energy costs. It also empowers end users by giving them an active role in their power usage.[6]

Other examples of a Distributed Energy Platforms (DEP) in the USA and Canada are the Advanced Energy Management Platform (AEMP) developed by Enbala (now Generac) and Transactive Energy App developed by IEMS. The AEMP is a cloud-based software platform that enables the aggregation and orchestration of distributed energy resources (DERs) for grid optimization and demand response purposes. IEMS platform, supported by LG Nova, simulates and optimize the distribution network based on the predicted PV and Load profiles for any location and feeder capacity size in North America.

Microgrid – Public, Private

In cities across the country, various groups are undertaking Community Microgrid projects. A Community Microgrid uses localized distributed energy resources (DER), such as renewable energy, to power a local grid area of up to several thousand consumers. Microgrids are of interest to many communities because they can provide critical facilities with electrical power during widespread outages, brownouts, blackouts, or substation failures. Additionally, Community Microgrids can participate in demand response events to assist utility companies with maintaining service levels. There are, however, challenges associated with Microgrids because there is potential for back-feeding into a spot network (with no direct ties to the street grid). Uncertainty in supply and the ability to store excess energy, especially in relation to weather unpredictability, can also challenge the efficacy of Community Microgrid operations.

Solar and Wind Renewable Energy Systems (RES)

Solar and wind energy systems are fast-growing means to offset or reduce electric loads. However, these systems need to be monitored to ensure that operations return investments for their owners. Net Metering and Remote Net Metering results should be reviewed in order to understand the benefits of a renewable energy system. Numerous companies in the market can provide guidance in this area. Live data can be sent to cloud-based systems where vendors can review it and provide recommendations to help reduce operating and utility costs.

NZEB RES Targets and Climate Response KPIs:

Following are some of the KPIs which can be used to evaluate meeting the RES targets and climate response:

Degree of Energetic Self-Supply by RES (%) The ratio of locally produced energy from RES and consumption over a time period.

Increased RES and Distributed Energy Resources hosting capacity (%): The additional RES and energy resources that can be installed in the network when new interventions are applied and compared to the BAU scenario.

Load Cover Factor (%): The percentage of electrical demand covered by on-site electric generation.

Energy Storage systems

Utilities, municipalities, and operators of smart buildings need to consider the best (and smartest) way to provide energy to citizens. Renewable energy is crucial in providing energy services to power buildings and their smart technologies. Batteries and thermal energy solutions can help offset the limitations of renewable energy sources. They should be considered in critical facilities where the potential exists for brownouts or blackouts because they can assure constant voltage to mission-critical devices.

Building as a Battery

Batteries have been used in communication networks for years. Technology today affords opportunities for incorporation into even the average facility that requires continuous, uninterrupted service. They can be installed in buildings to maintain lighting, data centers and/or other critical systems. The demand for more efficient batteries for electric vehicles is improving the storage capabilities of batteries and reducing their size. These systems can also be integrated with renewable energy sources, such as solar power, to provide constant electricity during peak load periods. The deployment of electric cars may enable car batteries to power buildings through vehicle-to-grid (V2G) technology. This system allows electric vehicles (EVs) to communicate and interact with the power grid in order to sell demand response services by returning electricity to the grid or by throttling their charging rate. This means that when an electric vehicle is plugged into a charging station, it could either be charging its battery or sending energy back to the grid or building. This could help to provide a more stable and efficient energy grid, especially in times of high demand or during power outages, as electric cars can be seen as a distributed network of energy storage units that can be used to balance the load.

Thermal Energy Storage

An Integrated Thermal Energy Storage System (ITESS) using chilled water can provide additional sub-cooling for an air conditioning system’s condenser, thereby increasing the entire system's capacity and significantly reducing electric demand and consumption. ITESS uses a dedicated chiller to cool a thermal storage tank, typically at night when electricity demand and rates are lower. This thermal reservoir is used the following day to sub-cool the refrigerant leaving the condenser. This additional cooling increases the cooling capacity and decreases electrical demand during hot days for an existing or new vapor compression system.[7]

Another approach to both thermal and regeneration of electrical power is NREL’s ENDURING project, which aims to store thermal energy for up to four days, cycle for 30 years or more, and cost no more than 2.5 cents per kWh. To keep costs low for standalone thermal storage, NREL designed a system repurposing existing turbines and grain silo technology. The ENDURING met the challenge of demonstrating that it can store and release power from a 26,000 MWh particle-based thermal energy storage system via a 130 MW electric generation system for up to four days; 100 hours. The system is scalable to supply power for local communities or regional utility grids.

Energy Storage Response KPIs:

Energy storage can be evaluated by following KPI: Storage Efficiency (%): The ratio between discharged and charged energy, typically over a full cycle.

Case Studies

Several utilities around the world are starting to embrace grid-connected building technologies as a way to improve energy efficiency, reduce costs, and provide better services to their customers. Some examples of utilities that are embracing connected building technologies include:

  1. Enel: Enel[8] is an Italian utility that has implemented a program called Open Meter, which uses connected building technology to monitor energy usage in real-time and provide customers with insights into how they can reduce their energy consumption. The program has been successful in reducing energy usage and lowering costs for both Enel and its customers.
  2. Tokyo Electric Power Company (TEPCO): TEPCO[9] is a Japanese utility that has implemented a program called Smart House, which uses connected building technology to monitor energy usage and control home appliances remotely. The program has been successful in reducing energy usage and improving the reliability of the power grid.
  3. Ausgrid: Ausgrid[10] is an Australian utility that has implemented a program called Power2U, which uses connected building technology to monitor energy usage and provide customers with insights into how they can reduce their energy consumption. The program has been successful in reducing energy usage and lowering costs for both Ausgrid and its customers.
  4. Pacific Gas and Electric (PG&E): PG&E is one of the largest utilities in the United States and has implemented a program called SmartRate, which offers customers discounted rates for using energy during off-peak hours. The program uses connected building technology to monitor energy usage in real-time and provide customers with insights into how they can reduce their energy consumption.

The U.S. Department of Energy (DOE) awarded $61 million from its Connected Communities funding opportunity announcement for 10 projects that will demonstrate how energy-efficient and grid-interactive technologies can transform homes and workplaces into connected communities.[11] The Connected Communities funding opportunity is led by DOE’s Building Technologies Office in collaboration with the Solar Energy Technologies Office, the Vehicle Technologies Office, the Office of Electricity, and Lawrence Berkeley National Laboratory. The selected communities were: IBACOS Inc. of Pittsburgh, Pennsylvania

  • Scale of Demand Flexibility: 3.8 MW of flexible load to serve grid needs
  • Expected Energy Savings: Estimated 20% savings compared to baseline energy performance
  • Planned Location of Buildings: Within Duke Energy’s North Carolina utility service area

IBACOS Inc. will work with the National Renewable Energy Laboratory, Tierra Resource Consultants, Energy and Environmental Economics Inc., Meritage Homes, Duke Energy, Energy Hub and Elevation Home Energy Solutions to deliver 3.8 MWs of aggregated flexible load from a comprehensive mix of distributed energy resources (DERs) deployed in 1,000 residential dwellings including new and existing single-family and multifamily owner-occupied and rental properties in Duke Energy’s North Carolina service area. This project implements key energy-efficiency upgrades for existing properties and will explore the capabilities of a connected network of DER technologies to deliver flexible distributed capacity at scale. The data collected from this project, including occupant experience data, will provide real-world insight on the aggregated grid impacts across a large service area.

Spokane Edo LLC of Seattle, Washington

  • Scale of Demand Flexibility: 1-2.25 MW flexible load
  • Expected Energy Savings: Up to 900 MW hours per year in energy savings
  • Planned Location of Buildings: Spokane, Washington

Spokane Edo LLC will work with Avista Utilities, McKinstry, Pacific Northwest National Laboratory, and Urbanova to upgrade up to 125 existing residential and commercial buildings. The team will implement energy-efficiency measures and DERs across a variety of Spokane’s residential and commercial buildings to provide up to 2.25 MW of flexible load and grid benefits. Specifically, the project will demonstrate non-wire alternatives in its retrofits, thereby avoiding major capital investments in distribution infrastructure by creating virtual power plants from existing buildings. The project recruitment will be focused on equity across all customer demographics, including highly impacted and vulnerable populations in Spokane’s Opportunity Zones.

The Ohio State University of Columbus, Ohio

  • Scale of Demand Flexibility: More than 2 MW flexible load a peak
  • Expected Energy Savings: 35% energy reduction compared to 2017 baseline
  • Planned Location of Buildings: Columbus, Ohio

Ohio State will work with ENGIE North America Inc., National Renewable Energy Laboratory, and the University of California – Berkeley to demonstrate novel GEB capabilities across 20 diverse campus buildings. Leveraging an existing mature connected campus, this project team will explore ancillary grid services across its university campus. The project will demonstrate a cybersecure predictive control of buildings and DERs to provide important but overlooked grid services like frequency regulation, synchronized reserve, and energy and capacity markets participation. Given the mature existing connected campus technologies, this project will have the opportunity to explore data privacy and cybersecurity plans, business models for institutional energy management, and occupant comfort across a range of building types and DER assets.

Open Market ESCO Limited Liability Company of Boston, Massachusetts

  • Scale of Demand Flexibility: 1.2 MW (4 hour) to 4 MW (30 min.) building flexible load
  • Expected Energy Savings: 30% energy reduction
  • Planned Location of Buildings: Lowell, Massachusetts

Open Market ESCO LLC will work with Fraunhofer USA Inc., Cpower, Clean Energy Group, Logical Buildings, Sparhawk Group, SunRun, and Massachusetts Department of Housing and Community Development to implement energy-saving and flexible technologies across 2,000 homes. The project seeks to demonstrate the financeable pathways for existing affordable multifamily housing to become grid-interactive efficient buildings. This project will enroll up to 20 low-moderate apartment communities to strategically deploy and implement efficiency, demand flexibility, renewable generation, and energy storage. The project team plans to focus on energy equity and will demonstrate pathways for bringing energy savings, resilience, comfort, and environmental benefits to these underserved communities.

Portland General Electric of Portland, Oregon

  • Scale of Demand Flexibility: 1.4 MW of flexible loads
  • Planned Location of Buildings: Portland, Oregon

Portland General Electric of Portland, Oregon will work with Energy Trust of Oregon, Northwest Energy Efficiency Alliance, Community Energy Project, National Energy Renewable Laboratory, and Open Systems International Inc. to retrofit more than 500 North Portland’s historically underserved neighborhoods to reduce their energy burden with numerous energy efficiency measures and connected devices that provide the grid with a range on energy services. (Award amount: $6.65M) SmartGrid Advanced Load Management & Optimized Neighborhood (SALMON). This project builds on a solid foundation of Portland General Electric’s Smart Grid Testbed, to demonstrate 1.4 MW of flexible loads, reduce the energy burden of low-income residents, and explore new ways to reach historically underserved communities. The project aims to utilize various energy-efficiency measures and connected devices, including smart thermostats and water heaters, and PGE’s Advanced Distribution and DER Management Systems. Through its previous testbed success, this project team anticipates high levels of participation in and awareness of their flexible load programs, and strong community engagement and adoption.

SunPower Corp. of San Jose, California

  • Scale of Demand Flexibility: 200-700 kW
  • Expected Energy Savings: 38-57% improvement in efficiency
  • Planned Location of Buildings: Menifee, California

SunPower Corp. of San Jose, California will work with KB Home, the University of California – Irvine, Schneider Electric, and Southern California Edison to develop two new home communities including more than 230 homes. This project team will develop two testbeds with state-of-the-art new residential buildings that meet DOE’s Zero Energy Ready Homes criteria. Each all-electric community will implement photovoltaic systems and home energy management systems, however the two communities will compare benefits of community level versus residential level energy storage batteries, while providing grid services to the local utility. This project may be the blueprint to follow for building new decarbonized homes of the future.

Post Road Foundation of Oakland, California

  • Scale of Demand Flexibility: 1.1 - 2.5 MW for up to 3 hours
  • Expected Energy Savings: 16% from efficiency measures
  • Planned Location of Buildings: New Hampshire, Maine

Post Road Foundation will work with New Hampshire Electric Cooperative, Efficiency Maine Trust, SLAC National Accelerator Laboratory, and Knowledge Problem, LLC. to deploy a Transactive Energy Service System (TESS) platform that enables grid-interactive control through two-way communication between DERs and a local energy market. The project will test TESS in three rural communities in New Hampshire and Maine, each consisting of 100 to 250 single-family homes, small commercial buildings, and small industrial customers. The team expects that TESS will be able to do the following:

  • Facilitate more effective use of distribution systems through load flexibility, with applications such as peak load management.
  • Reveal the financial value of DER deployment on a distribution system.
  • Lower financial and engineering hurdles to beneficial electrification.

Slipstream Group Inc. of Madison, Wisconsin

  • Scale of Demand Flexibility: 216 kW of flexible load
  • Expected Energy Savings: 39% total energy savings
  • Planned Location of Buildings: Madison, Wisconsin

Slipstream Group Inc., in partnership with Madison Gas and Electric, the City of Madison, Rocky Mountain Institute, the American Council for an Energy-Efficient Economy, and bluEvolution, will convert approximately 15 facilities in Madison, Wisconsin, to GEBs and add nearby electric vehicle charging. As these improvements demonstrate reliable and cost-effective efficiency and demand flexibility improvements, the project will expand to additional privately owned buildings, providing a scalable business model for utilities to install demand flexibility and energy-efficiency upgrades across multiple building sizes in the public and private sectors. The project will also deliver a GEB toolkit with integrated financing options to address opportunities in public and private buildings across multiple sizes and use cases.

PacifiCorp doing business as Rocky Mountain Power of Salt Lake City, Utah

  • Scale of Demand Flexibility: Over 8 MW flexible load
  • Expected Energy Savings: 30% energy savings compared to typical buildings
  • Planned Location of Buildings: Herriman, Salt Lake City, and North Logan, Utah

PacifiCorp of Portland, Oregon, will work with Pacific Northwest National Laboratory, Utah State University, Wasatch Energy Group, GIV Group, Utah Transit Authority, Packsize International, Open Systems International, and Sonnen to implement a utility-managed DER control program that integrates diverse building types with a range of flexible loads to optimize grid services and improve building energy efficiency. The team identified a diverse but representative set of buildings that range from a large suburban apartment complex, downtown complex of mixed-use retail and apartments, university laboratory and office building with a microgrid, a mass transit transportation center, manufacturing building, and residential home. These buildings are in various stages of development with some in operation, some currently under construction, and others where the team can influence the design. The buildings are all-electric and will have advanced energy-efficiency technologies with efficient heat pump-based HVAC (both central and mini-splits) and domestic hot water, adaptive building envelope, and advanced lighting achieving a minimum of 30% energy efficiency compared to the baseline of typical buildings.

Electric Power Research Institute Inc. of Palo Alto, California

  • Scale of Demand Flexibility: 2.6 MW flexible load
  • Expected Energy Savings: 30% energy savings
  • Planned Location of Buildings: Proposed for New York City, New York; Seattle, Washington; and San Diego, California

Electric Power Research Institute Inc. will work with Gas Technology Institute, Seattle City Light, Community Roots Housing, Vistar Energy, and Sentient Buildings to transform multifamily buildings in multifamily disadvantaged communities into Grid-interactive Efficient Buildings. The project team will retrofit affordable housing communities in three geographically dispersed cities – New York, Seattle, and San Diego -- with a total of over 2,000 dwellings. By implementing efficiency, flexibility, storage, and distributed generation the project team will demonstrate different decarbonization pathways, reduce energy cost burden, improve system resilience, and provide distribution and bulk grid services.

  1. DOE “A National Roadmap for Grid-Interactive Efficient Buildings” May 17,2021 https://gebroadmap.lbl.gov/A%20National%20Roadmap%20for%20GEBs%20-%20Final.pdf
  2. DOE “Grid-interactive Efficient Buildings” Project Summary, July 2020 DOE www.energy.gov/sites/default/files/2020/09/f79/bto-geb-project-summary-093020.pdf
  3. Smart Cities and Communities: A Key Performance Indicators Framework https://www.nist.gov/publications/smart-cities-and-communities-key-performance-indicators-framework
  4. US DoE: Demand Dispatch—Intelligent Demand for a More Efficient Grid https://netl.doe.gov/sites/default/files/Smartgrid/DemandDispatch_08112011.pdf
  5. Blockchain Technology Overview, NISTIR 8202 https://nvlpubs.nist.gov/nistpubs/ir/2018/NIST.IR.8202.pdf
  6. Smart stuff: IQ of Northwest power grid raised, energy saved https://www.pnnl.gov/news/release.aspx?id=4210
  7. NYSERDA: Integrated Thermal Energy Storage for Cooling Applications https://www.nyserda.ny.gov/-/media/Project/Nyserda/Files/Publications/Research/Other-Technical-Reports/17-17-Integrated-Thermal-Energy-Storage-for-Cooling-Applications.pdf
  8. Grid Futurability® for a Net-Zero World https://www.climateaction.org/events/digital/grid-futurability-for-a-net-zero-world
  9. TEPCO: A quiet emergence of Smart-Grid in Japan (Digitization) https://d3.harvard.edu/platform-rctom/submission/tepco-a-quiet-emergence-of-smart-grid-in-japan-digitization/
  10. Ausgrid: Solar and Lighting Incentive Project https://www.ausgrid.com.au/Industry/Demand-Management/Power2U-Progam/Solar-and-Lighting-Upgrades and https://arena.gov.au/projects/ausgrid-power2u/
  11. DOE “Meet DOE’s Newest Connected Communities of Grid-interactive Efficient Buildings” https://www.energy.gov/eere/buildings/articles/meet-does-newest-connected-communities-grid-interactive-efficient-buildings