Electrical Submetering at Cadman Plaza North as an Enabling Technology for Price Sensitive Load Management

Cadman Plaza North, a master-metered, high-rise cooperative located at 140 Cadman Plaza West in downtown Brooklyn, NY implemented electrical submetering during 2003 utilizing the NYSERDA sponsored CEM program to help fund this conversion. This cooperative was originally built under the New York City Mitchell-Lama program and contains 250 apartments, all occupied by shareholders. A dual fuel (natural gas/#2 oil) boiler system provides steam for heating. Each apartment is cooled by electric powered through the wall air conditioners.

Equipment – A wireless submetering system

The installed submeter contains an integral temperature sensor and is wall mounted adjacent to the apartment circuit breaker panel. The temperature sensor provides management the ability to monitor apartment temperatures and to optimize the building heating system distribution and operation. This feature assists in addressing resident heat complaints and results in significant fuel savings.

Billing History

Baseline year before submetering


Most recent year after submetering

An analysis of the building electrical data was conducted by Herbert E. Hirschfeld, P.E. in order to determine the impact of electrical submetering on the building complex’s electrical usage (kWh), demand (KW) and associated utility and ESCO electric costs. In order to determine the building’s cost benefit (or cost avoidance) due to submetering, the base line period (08/31/00 – 08/31/01) which was established during the submetering feasibility evaluation prior to submetering implementation was adjusted based on prevailing electric costs and weather data (cooling degree days or CDD) which occurred during a recent time period of comparison (05/03/07 – 05/02/08) after submetering. In this example the difference between the adjusted baseline period and the current period yielded an adjusted reduction in usage of 367,599 kWh or 19.1% and a cost avoidance (or cost benefit) of $74,521 which represents 19.7% of the adjusted total building complex’s electric costs. Additionally, there was a reduction in peak demand of approximately 22.4% which would have resulted in Cadman Plaza North obtaining additional financial incentives by participating in the New York State Independent System Operator (ISO) Curtailment program.

Resultant Adjusted Reduction in Usage of 367,599 kWh or 19.1% and a Cost Avoidance from Electrical Submetering of $74,521 or 19.7%, as well as a Reduction in Billing Demand of 22.4%
Submeter Online

Contributed by Herbert E. Hirschfeld, P. E.