Apartment buildings, especially older buildings with boiler systems, can have unique challenges for balancing competing goals of occupant comfort and lowering operating costs. Instrumenting a building with HVAC sensors, potentially each apartment unit, can provide a comprehensive building footprint from which to better optimize energy consumption and lower costs. The apartment sensor can be combined with outside measurements into a Building Automation System, or just a small controller, which can make more intelligent and predictive decisions for boiler control.
Implementing a wired sensor solution is prohibitively expensive for existing buildings. In addition, the disruption to occupant living space can be a coordination and construction nightmare. Wireless sensors, on the other hand, provide a more cost effective and occupant-friendly implementation approach. They can be installed in seconds to a few minutes and there is no construction mess. The primary challenge with wireless sensors has been battery life, with most devices operating for only 3-5 years before the batteries need to be replaced. Scheduling time and expense for battery replacement can not only be expensive, but also a nuisance to occupants.
Powercast’s wireless sensors can operate for over 25 years on a single battery (test report) and effectively eliminate battery replacement. This means there is only a quick, one-time visit to the apartment unit to install a sensor, or it can be easily added to a routine maintenance call until all units are equipped.
As a network-based solution, data from up to 100 devices can be received by a single wireless gateway (WSG-101/102) and made available to a building automation system or system controller. Wireless range for a 900MHz system is up to 300 feet indoors, and range can be extended to unlimited distance using wireless repeaters.