Final Report: I-SAVE: An Interactive Real-time Monitor and Controller to Influence Energy Conservation Behavior by Impulse Saving

EPA Grant Number: SU834700
Title: I-SAVE: An Interactive Real-time Monitor and Controller to Influence Energy Conservation Behavior by Impulse Saving
Investigators: Alahmad, Mahmoud , Bergstedt, Sean , Brow, Caitlin , Brumbaugh, Adam , Ci, Song , Hasna, Hosen , Nader, Wisam , Sordiashie, Evans , Wang, Xueyi , Wisnieski, Tim
Institution: University of Nebraska at Lincoln
EPA Project Officer: Nolt-Helms, Cynthia
Phase: I
Project Period: August 15, 2010 through August 14, 2011
Project Amount: $10,000
RFA: P3 Awards: A National Student Design Competition for Sustainability Focusing on People, Prosperity and the Planet (2010) RFA Text |  Recipients Lists
Research Category: Pollution Prevention/Sustainable Development , P3 Challenge Area - Built Environment , P3 Challenge Area - Energy , P3 Awards , Sustainability


The 2010 Annual Energy Outlook indicates a 14% increase in U.S. primary energy consumption from 2008 to 2035, an average annual growth rate of 0.5%. Further, CO2 emissions are projected to increase by 0.3% per year for the same time frame. This increase is mostly due to the electric power and transportation sectors [1]. The electrical distribution system particularly plays a role in the built environment as it is an enabling product, an intangible necessity used to power our systems [2]. According to United States Green Building Council (USGBC), the built environment in the United States accounts for 72% of electricity consumption, 39% of energy use, 38% of all CO2 emissions, 40% of raw materials use, 30% of waste output (136 million tons annually), and 14% of potable water consumption [3]. U.S. homes use about one-fifth of the total energy consumed in the nation and about 60% of that is in the form of electricity. The residential sector, unlike the commercial and industrial sectors, is made up of multiple small energy users such as houses, mobile homes, and apartments. Research has shown that these residential energy consumers waste almost 41% of the power supplied to their homes [4]. The large amount of usage and waste indicates that the residential sector has significant energy savings potential. A study in USA has put the value of deferring network upgrade work at approximately $650/KW for transmission and $1050/KW for distribution network [5].

To alleviate the information burden and guesswork about energy waste, we proposed a bottom-up approach to energy conservation via I-SAVE, an interactive real-time monitor and controller (RTMC) system as shown in Figure 1. I-SAVE is based on an instantaneous impulse savings behavior that provides users with the ability to reduce energy usage in real time for the entire home by pressing a button. The I-SAVE’s user friendly interface with Go-green save-energy button is based on an adaptive system that monitors and controls real energy consumption at every energy consumption location or node. A node is defined as a point on the wiring system in the building at which electrical current is taken to supply utilization equipment (loads) [4]. Common nodes include receptacle, lighting switch, dedicated load, etc. I-SAVE will effectively determine non-critical and wasted energy in home and provide users with the ability to turn off wasted energy with the Go-green save-energy button. This will result in total power consumption for the home to be at its optimal level while also maintaining occupant comfort.

The specific objectives of I-SAVE are to:

  1. Identify, analyze, model, simulate, and demonstrate various electrical loads (lights, portable electronics, entertainment equipment, coffee makers, toasters, etc.) related to energy consumption and conservation in residential homes.
  2. Design and develop a proof-of-concept controller to determine current loads and status, real-time energy consumption, and utilize additional sensor information to evaluate if energy is being wasted.
  3. Design, develop, build, demonstrate, and test a prototype I-SAVE RTMC system as a proof-of-concept to change behavior and save energy based on an impulse response.
  4. Use the proof-of-concept system as a hands-on demonstration in the classroom and to conduct surveys and evaluate results for impulse behavior for the community.

Summary/Accomplishments (Outputs/Outcomes):

A prototype I-SAVE RTMC has been designed and tested. Figure 1 shows the circuit diagram and the built board to simulate six loads.

Figure 1: I-SAVE prototype: (a) RTPMC Circuit Diagram. (b) RTPMC Prototype Board

We integrated the output of the board with a virtual environment model to illustrate our physical/virtual system. The pushbutton system will be demonstrated during the Expo. The virtual environment is built, using Visual Basic, for the prototype that emulates a room in ZNETH house. It provides the user with a simple interface that combines the actual layout of the room with real-time power consumption at every electrical node. Each load in this room is associated with one of the loads in the RTPMC prototype. When power is consumed at a load location, a red circle with a thickness proportional to the power consumption of that load will show up, indicating which load is consuming power in real time.

Fig. 2 shows real time power consumption by means of read circles, Excess (wasted) energy consumption is also highlighted at two locations. Although these two loads are turned off, they still consume power (phantom load). The red indicators function as warning sign for users to take action to conserve energy and minimize waste.

Figure 2: I-SAVE prototype in Operation: (a) phantom loads (b) Real-Time Power Monitoring


I-SAVE has the following estimated benefits with respect to people, prosperity, and the planet:

  • A 20% expected energy savings with an approximate $300-$400 saving per year.
  • Developing two components: the physical I-SAVE system and the virtual I-SAVE system. This is expected to translate into potential businesses by the research team or patented for collaboration with external businesses in this field.
  • People will be more satisfied with their behavior when they are making monitory and energy saving by utilizing the Go-green energy button. This will promote sustainable design, create new job opportunities, and make this planet a better place to live.
  • With a 127 Million homes in the U.S., approximately 7.7 GW of energy is required to maintain loads in standby mode only; we are targeting a 20% reduction in this context.

I-SAVE addressed an existing gap in home/building automation (i.e., control of energy consumption based on impulse behavior and user comfort). I-SAVE overcomes this challenge since the user will make a decision to save energy by pressing the go-green button, if the results are not satisfactory for them, he/she can simply cancel the changes that I-SAVE has made by pressing the go-green button again, or instead, the user can still make specific changes to some of the loads rather than cancelling all of the changes that I-SAVE has just made. This will allow I-SAVE to learn about the user’s preference and adapt its control algorithm to accommodate the user’s convenience, since people have different needs and preferences. This made us realize that a comprehensive control algorithm for entire building automation does not exist and implies that any building control algorithm should be adaptive and capable of learning/understanding the user’s attitudes toward energy consumption. Bringing about such “green” systems will make a big difference in terms of the energy wasted in our buildings, thus reducing harmful emissions and creating a lot of job opportunities by developing and installing such systems.

Journal Articles:

No journal articles submitted with this report: View all 2 publications for this project

Supplemental Keywords:

Energy recovery, Conservation, Consumption, Real-Time Power Monitoring, Monitoring Resource Consumption, Smart Buildings, Model for Sustainability, Interactive Development Tools, Decision-making, Virtual Model, ZNEH

Relevant Websites:

Lights Out - A Sensor That Cuts Your Electricity Usage Exit
The Phantom of the Outlet Exit