Real time metering for Singapore schools: A case study

The Government of Singapore decided in March 2000 to restructure the electricity and gas industries and put in place a market structure and regulatory framework to enhance competition. Subsequently the Building and Construction Authority of Singapore (BCA) has established Energy Efficiency Indices, and it intends to conduct energy audits of a sample of buildings with high energy consumption, including offices, hotels, shopping complexes, hospitals and other institutions. The project will commence with a pilot scheme involving several government buildings.

PWD EMS, a subsidiary of the PWD Corporation Pte Ltd, has a management portfolio of more than one thousand buildings and facilities in and around Singapore. Having managed large government facilities such as office buildings and schools, PWD EMS has discovered synergy in entering the liberalised energy market as an energy retailer. 

PWD EMS required a low-cost solution to provide energy efficiencies, real time metering and rich functionality. In addition, energy profiling software was required to display energy usage data and detect unusual or unexpected patterns. The ideal solution would consist of an integrated energy management and automated reading system and a preliminary market survey yielded a plethora of products from several different manufacturers.

Solution

Eka Systems, Inc., which provides feature-rich low cost energy management and automated metering systems, was selected to provide its BlueMeter energy management system for an initial pilot at a local school system. This consists of Eka’s EnergyInsight™ energy management and visualisation software, along with its Bluetooth™-based real time metering technology.

The solution is designed to provide the rich features of more expensive systems at a price that is cost effective for smaller commercial and industrial companies and school districts. Submeters were installed in to accurately determine the energy consumption within different parts of the school (Figure 1).

All the meters were networked together using Bluetooth wireless technology. The wireless BlueMeter hub provides a gateway to the local wireless meter network, which can be accessed from the Internet or a phone line. The school authorities obtain the meter data locally by simply accessing the BlueMeter hub installed on their corporate intranet. Data is also being accessed remotely through a dial-up connection by Singapore PWD for billing purposes. Since real time consumption information is available, the system enables time-of-use billing. 

Once installed, there are no recurring costs associated with data communication, which can be either schedule or demand-driven, as the technology permits bi-directional data communications. As Bluetooth works in the unlicensed 2.4 GHz band, there are also no transaction costs associated with data collection. In addition, since the wireless technology is plug-and-play, there is no need for wiring or other major installation operations (Figures 2 and 3).

Once installed, the system proved to be of immediate benefit to the school authorities. Even though the school was in recess for the holidays, the energy consumption data showed an unexpected peak and surge early in the morning (Figure 4). The school authorities were immediately alerted and an electrician was called to investigate the problem. As the anomaly lasted for a period of two hours each day, its fixing is expected to directly impact on the school’s energy bill.

The use of Eka’s EnergyInsight and BlueMeter products are expected to result in significant savings across the entire school system in Singapore.