NASA Site Survey, Thorough Analysis, and Energy Audit for NASA’s Building 46
Challenge: NASA is required to reduce their energy consumption by 3% each year, leading to 30% by the end of fiscal year (FY) 2015, as compared to an FY 2003 baseline. Johnson Space Center (JSC) is also required to perform energy audits on their facilities once every year in an effort to reduce energy consumption and optimize building system performance for all buildings. This building survey and report is an ASHRAE Level I report, with aspects included for an ASHRAE Level II audit which was developed from ASHRAE guidelines combined with a retro-commissioning report. The goal of the survey and report is to provide a comprehensive evaluation of the building systems operation and energy performance and to identify any improvements that would assist JSC in meeting its energy reduction goal.
Solution: PTS assembled a team of engineers to assist in developing the auditing requirements as well as perform the Building 46 energy audit and functional testing. This included working with on-site NASA personnel and the maintenance contractor to determine the condition of the building systems and identify any Energy Conservation Measures (ECMs) that could be feasibly implemented. The survey was started with a kick-off which was followed by data collection and functional testing. Observations, deficiencies and recommendations were all compiled in a final report.
In addition to the functional testing of primary air handling units and pumps, the team focused on:
Review drawings and equipment schedules
- Building control and automation system (controlled devices and control loops)
- Existing local control strategies
- Spot measurements of temperatures and electrical current
- Review of existing ventilation air requirements
- Review of existing exhaust make up and transfer air requirements
- Building envelope integrity
- Lighting and Electrical System
- Steam System
- Chilled Water System
- Compressed Air
- Domestic hot water
- Discrepancies between EBI and the field
Recommended Energy Conservation Measures
Example: ECM# 1: Return AHU 3 to VAV System: AHU 3 was designed and is mostly installed to be operated as a VAV system. The fan is a variable pitch unit and there are VAV boxes installed throughout the ductwork.
Recommendation: The recommended strategy to reduce energy consumption at AHU 3 is to connect the existing VAV boxes and local zone thermostats into the BCS control system via digital controls. This will allow the system to respond to local zone conditions to reduce airflow and control the discharge temperature to match the demand in the space. By also replacing the variable pitch fan with a variable frequency drive connected to BCS and EBI, the operating conditions of the fan will be able to be monitored and controlled to match the airflow demand of the system and reduce electricity consumption.
- Total Electrical Savings per Year: 53,556.8 kWh
- Total Cost Savings per Year: $3,159.85
- Estimated Project Cost: $20,000.00
Benefits: As a result of the energy assessment and retro-commissioning effort PTS was able to identify and recommend six (6) Energy Conservation Measures (ECMs) for NASA to consider. Implementation of all of the recommended ECMs in the report will reduce the facility electrical demand by up to 25 kW and result in an estimated annual savings of 349,206 kWh, 157 MMBtu of steam, 880.8 MMBtu of chilled water and 45,496 gallons of water. In addition to the reduction in energy savings, PTS estimates that the ECMs will result in an annual utility savings of $21,543.17. In addition to the ECMs, PTS also identified and made recommendations for twenty two (22) maintenance and repair deficiencies and thirteen (13) configuration control deficiencies. By having PTS perform the energy assessment and implementing the recommendations in the report, NASA will increase system efficiencies, reduce operating costs, improve the overall control and operation of the building equipment and increase the accuracy of system monitoring and trending.