The Prius Effect is a psychological phenomenon related to the Hawthorne effect. Rather than productivity changes as the result of system changes, the Prius Effect is characterized by changes in behaviour as the result of self-monitoring. The Prius Effect came into prominence due to the Toyota Prius's real-time mileage feedback from their dashboard. The impact can also be observed in areas such as building energy monitoring, though can be as simple as the presence of a clock influencing worker efficiency. The opposite effect might be the delay in financial information from credit card use resulting


Data Collection edit

Energy Management Software collects real-time interval data, with intervals as short as one minute. The data are collected from interval meters, Building Automation Systems (BAS), directly from utilities, or other sources. Furthermore, past bills can be used to provide a comparison between pre- and post-EMS energy consumption.

Electricity and Natural Gas are the most common utilities measured, though systems may monitor steam, petroleum or other energy uses, water use, and even distributed generation.

Reporting edit

Reporting tools are targeted at owners and executives who want to automate energy and emissions auditing. Cost and consumption data from a number of buildings can be aggregated or compared with the software, saving time relative to manual reporting. EMS offers more detailed energy information than utility billing can provide; another advantage is that outside factors affecting energy use, such as weather or building occupancy, can be accounted for as part of the reporting process. This information can be used to prioritize energy savings initiatives and balance energy savings against energy-related capital expenditures.

Bill verification can be used to compare metered consumption against billed consumption. Bill analysis can also demonstrate the impact of different energy costs, for example by comparing electrical demand charges to consumption costs.

Greenhouse gas (GHG) accounting can calculate direct or indirect GHG emissions, which may be used for internal reporting or Enterprise Carbon Accounting.


Monitoring edit

Monitoring tools track and display real-time and historical data. Often, EMS includes various benchmarking tools, such as energy consumption per square foot, weather normalization or more advanced analysis using energy modelling algorithms to identify anomalous consumption. Seeing exactly when energy is used, combined with anomaly recognition, can allow Facility or Energy Managers to identify savings opportunities.

Initiatives such as demand shaving, replacement of malfunctioning equipment, retrofits of inefficient equipment, and removal of unnecessary loads can be discovered and coordinated using the EMS. For example, an unexpected energy spike at a specific time each day may indicate an improperly set or malfunctioning timer. These tools can also be used for Energy Monitoring and Targeting. EMS uses models to correct for variable factors such as weather when performing historical comparisons to verify the effect of conservation and efficiency initiatives.

EMS may offer alerts, via text or email messages, when consumption values exceed pre-defined thresholds based on consumption or cost. These thresholds may be set at absolute levels, or use an energy model to determine when consumption is abnormally high or low.


Engagement edit

The main objective of Engagement is to connect occupants’ daily choices with building energy consumption. By displaying real-time consumption information, occupants see the immediate impact of their actions. The software can be used to promote energy conservation initiatives, offer advice to the occupants, or provide a forum for feedback on sustainability initiatives.

Letting occupants know their real-time consumption alone can be responsible for a 7% reduction in energy consumption1. EMS can also be used to quantify and demonstrate sustainable practices to potential employees and clients.


See Also: Building Automation System Energy Monitoring and Targeting

References: 1 Elizabeth Dickinson(2008-10-7) “The Prius Effect” American City Retrieved on 2009-05-12 [1]