To operate, ORNL requires energy and water. Goals to improve sustainability by FY 2025 include:
- reducing energy intensity for goal subject facilities by 25%, relative to the FY 2015 baseline,
- use 30% renewable energy,
- use 25% clean energy, and
- reduce potable water intensity by 36%, relative to the FY 2007 baseline.
ORNL has had significant achievements in reducing energy and water use, including:
- 7% reduction in energy use intensity (BTU/SF) since 2015, and
- 24% reduction in potable water intensity (Gal/SF) since 2007.
An energy audit, completed in 2010, identified Energy Conservation Measures that can further reduce ORNL's energy use.
An Energy Savings Performance Contract (ESPC) with Johnson Controls to reduce energy use that includes nine conservation measures:
- Central Steam Plant Biomass Solution
- Steam Line Updates
- Chiller Improvements 4509 Plant
- Building Management System Upgrades
- Advanced Electric Metering
- Comprehensive HVAC Upgrade
- Energy-Efficient Lighting Upgrade
- Water Conservation
- Wastewater Treatment Plant Replacement
Central Steam Plant Biomass Solution
ORNL is working to convert the laboratory's steam plant operations to a biomass-fueled boiler system. Biomass (i.e, renewable wood and wood products) will replace most of the natural gas and fuel oil currently used to provide steam to ORNL's physical plant operations.
In conjunction with the biomass project, the installation of a Cleaver-Brooks, Inc., Super Boiler will help reduce the ORNL steam plant's fossil fuel consumption by more than 70 percent, reducing the carbon equivalent of over 1 million tree seedlings grown in an urban environment for 10 years or 11,000 acres of pine fir forests. Furthermore, emissions reductions equate to 9,000 passenger vehicles or 120,000 barrels of oil consumed or the energy used by 4,500 homes in one year or 270 coal railcars.
Steam Line Updates
By installing wireless sensors and replacing faulty traps along the 12 miles of its steam lines, ORNL expects to save as much as $675,000 per year.
With 1,600 steam traps, which normally open slightly to discharge condensed steam with a negligible loss of live steam, the problem occurs when a trap fails and that failure goes undetected and unrepaired. Manual inspections of each trap are a daunting and sometimes dangerous task, but by collecting and monitoring data initially from 30 sensors at five steam trap locations, significant savings are expected.
Steam is used at ORNL, industrial sites, and universities throughout the nation for heating and cooling buildings. A DOE study, however, identified faulty steam traps as a major source of energy waste at industrial sites. "Approximately 20 percent of the steam leaving a central boiler plant is lost via leaking traps in typical space heating systems without proactive assessment programs," the report, "Steam Trap Performance Assessment," stated.
With this project ORNL researchers see a chance to save money, reduce the lab's carbon footprint, and lead by example. Working with Johnson Controls, ORNL has already repaired or replaced any faulty traps and is considering expanding the wireless sensor system by installing hundreds of sensors.
Wireless capability is "an ORNL hallmark," and this project leverages tools and technologies developed under the DOE Industrial Wireless Program. The sensors will monitor steam flow and temperature. The project will use the ORNL-developed Sensorpedia technology for standards-based information visualization.
Energy-Efficient Lighting Upgrade
The majority of ORNL buildings have T-8 fluorescent lighting systems installed. However, a significant number of standard efficiency T-12 fluorescent lighting systems with magnetic ballasts still exist. The T-12 lighting systems are not only inefficient, but also have unfavorable characteristics like ballast hum and lamp flicker.
Many service bays, warehouses, and storage areas around the Laboratory have High-Intensity Discharge (HID) lighting systems that feature metal halide and high-pressure lighting. Exterior lighting consists of a combination of high-pressure sodium, metal halide, and incandescent fixtures.
The ESPC provides for retrofit of existing lighting where feasible. [The nature of ESPC contracting does not support lighting retrofits in all areas. The energy services company (ESCO) has to carefully control equipment and installation costs to ensure savings to the Laboratory and profitability for the ESCO.] The retrofit in selected areas includes:
- removal and disposal of existing lamps and ballasts, fixture cleaning, replacement of yellowed or broken lenses, and the installation of new T-8 fluorescent lamps and electronic ballasts;
- replacement, where possible, of incandescent lamps with compact fluorescent lamps, T-8 fluorescent systems, or metal halide fixtures;
- replacement of some HID lighting with more efficient HID systems, high output T-8 fluorescent systems, or T-5 fluorescent systems;
- application of induction lighting for exterior fixtures, where feasible;
- changing, where possible, four-lamp fixtures to two-lamp fixtures with reflectors. The lumen output of the new fixture will be equal to that of the existing lighting fixture.
The benefits of implementing the lighting improvements include (1) improved energy efficiency and lower energy costs, (2) improved color rendering and indoor visual environment, (3) removal of the humming sound present with some magnetic ballasts, and (4) longer service life of equipment resulting in lower future maintenance costs.
The ESPC will implement water conservation measures in seventy-three buildings covering 2,960,000 square feet of space. The scope of this project includes the installation of faucet aerators, low-flow flush valves, low-flow toilets, and low-flow shower heads. Water consumption and the energy required to heat domestic hot water will be reduced. Water savings are projected at 12 million gallons each year.
Water usage at the central steam plant is being targeted as well. At that facility water conservation projects that focus on once-through cooling systems are projected to save 146 million gallons of water annually. Also, the biomass steam production project at the steam plant will save an additional 12 million gallons per year.
Finally, in order to avoid wasting water, all of the ORNL sprinkler systems have a rain delay mode. That rain delay setting requires each one to be unlocked and manually switched into that mode and then manually re-set to operations mode after the rain stops. There are about 12 separate controllers laboratory-wide, from High Flux Isotope Reactor (HFIR) to the Visitor Center.