Analysis of fuel savings associated with fuel computers in multifamily buildings. Final report [report]

M. McNamara, J. Anderson, E. Huggins
1993 unpublished
_|lt|flUlloIt OFTNIS O0_UI_.F.NT IS UNLIMITED .. NOTICE This report was prepared by EME Group in the course of performing work contracted for and sponsored by the New York State Energy Research and Development Authority (hereafter the "Energy Authority"). The opinions expressed in this report do not necessarily reflect those of the Energy Authority or the State of New York and reference to any specific product, service, process or method does not necessarily constitute an implied or expressed
more » ... lied or expressed recommendation or endorsement of same. Further, the Energy Authority, the State of New York and the contractor make no warranties or representations, expressed or implied, as to the fitness for particular purpose, merchantability of any product, apparatus or service or the usefulness, completeness or accuracy of any processes, methods or other information contained, described, disclosed or referred to in this report. The Energy Authority, the State of New York and the contractor make no representation that the use of any product, apparatus, process, method or other information will not infringe privately owned rights and will assume no liability for any loss, injury, or damage resulting from, or occurring in connection with, the use of information contained, described, disclosed, or referred to in this report. ABSTRACT This research was undertaken to quantify the energy savings associated with the installation of a direct monitoring control system (DMC) on steam heating plants in multi-family buildings located in the New York City metropolitan area. The primary objective was to determine whether fuel consumption was lower in buildings employing a DMC relative to those using the more common indirect monitoring control system (IMC) and if so, to what extent. The analysis compares the fuel consumption of 442 building over 12 months. The type of control system installed in these buildings was either a Heat-Timer (identified as IMC equipment) or a computer-based unit (identified as DMC equipment). IMC provides control by running the boiler for longer or shorter periods depending on outdoor temperature. This system is termed indirect because there is no feedback from indoor (apartment) temperatures to the control. DMC provides control by sensing apartment temperatures. In a typical multifamily building, sensors are hard wired to between 5 and 10 apartments sensors. The annual savings and simple payback were computed for the DMC buildings by comparing annual fuel consumption among the building groupings. The comparison is based on mean BTUs per degree day consumed annually and normalized for building characteristics, such as, equipment maintenance and boiler steady state efficiency as well as weather conditions. The average annual energy consumption for the DMC buildings was 14.1 percent less than the annual energy consumption for the IMC buildings. This represents 3,826 gallons of No.6 fuel oil or $2,295 at a price of $0.60 per gallon. A base DMC system costs from $8,400 to $10,000 installed depending on the number of sensors and complexity of the system. The standard IMC system costs from $2,000 to $3,000 installed. Based on this analysis the average simple payback is 2.or 4.0 years depending on either an upgrade from IMC to DMC (4.0 years) or a new installation (2.9) years. iii CONTENTS Section Pa_e
doi:10.2172/10176801 fatcat:bvjyz3dcang3doflytueevbaja