Sustainability Initiatives

Utilities

Utilities Master Plan | District Energy Systems | Steam System and Central Plant Upgrades
Boiler Pollution Controls | Chilled Water Utility | Water Audit Results

Utilities Master Plan

In 2005 the university conducted and completed its first comprehensive Utilities Master Plan. With approximately one million square feet (SF) of authorized new facilities in design or construction and another million SF of proposed new construction in the south and west portions of campus, the plan was critical to the university. These new facilities will impact all aspects of the current utility infrastructures.

The Utilities Master Plan consultant was not only able to take a practical look at the university's utility systems, but also analyzed and integrated sustainable energy solutions and flexibility to accommodate future technology. The plan also provides a vision for the long-term, as described in the executive summary (3.5 MB PDF) of the document.

District Energy Systems

Virginia Tech enjoys district energy systems for its steam and chilled water utilities. During heating months the steam demand is sufficient to operate a back pressure exhaust turbine capable of producing up to 6.5 MW of electricity. This cogeneration of electricity is energy and cost-efficient.

The central steam plant generates heat and electricity.

The central steam plant, a combined heat and power facility, requires less energy to cogenerate steam and electricity than would be needed to produce them separately. The total system (heating and cooling) load is low because the connected buildings do not peak simultaneously. The large size of the plant's large heating and cooling equipment increases efficiency by reducing the operating cost per unit of energy produced.

Replacing individual building heating and cooling equipment with a central energy system would result in significant energy and cost savings. Currently 6,863,591 SF from 103 campus buildings are heated from the central steam plant. Four chilled water district cooling plants air condition 2,917,921 SF across 35 campus buildings. The district cooling systems average 339 SF per ton of installed cooling capacity versus the individually cooled buildings' 175 GSF/ton. The university's district cooling systems are 94% more efficient than the individual building chiller systems.

The following are specific examples of energy efficiency opportunities offered by district energy systems.

Steam System Utility Distribution System and Central Plant Upgrades

This initiative realizes the specific recommendations of the above Utility Master Plan for the campus steam utility system and consists of eight separately designed and bid projects that will each contribute to the overall efficiency and enhanced environment.

1. Steam Distribution Repairs

   Steam pipe insulation and openings in the steam tunnels which may cause water infiltration will be repaired. The modifications will save the equivalent of 5,000 gallons of no. 2 fuel oil, or $10,000 per year.

2. Steam Distribution System Upgrades

   The 8" high-pressure steam piping and condensate return piping from the Central Steam Plant to the Life Sciences area will be replaced. The new piping will increase the capacity of the existing steam distribution system. Improved insulation on the high-pressure steam line will save the equivalent of about 74,000 gallons of no. 2 fuel oil, or $148,000 per year.

3. Summer Steam Condenser

   A new steam condenser mounted on the roof of the Central Steam Plant will provide increased steam load to facilitate operation of the coal fired boilers between May and October. Currently the campus steam demand is low, so gas fired boilers must be operated. Since it is not economically feasible to operate the steam turbine generator with steam produced from natural gas or fuel oil, no electricity is generated during these months. The new steam condenser will reduce fuel and electrical costs due to increased power production. The university will realize an immediate operational cost savings of between one and two million dollars annually upon project completion.

4. Boiler 8, 9, 10 Upgrade

   New economizers, combustion controls, and low Nox burners will be installed on each of the three existing gas fired boilers. Currently estimates predict a reduction of 10 tons per year in Nox emissions from the central steam plant as a result of this project. The upgrades will also increase the boilers' efficiency, resulting in an annual savings equivalent to 196,000 gallons of no. 2 fuel oil, or $392,000 per year.

5. Miscellaneous Plant Upgrades
   • a new deaerator for increased system redundancy
   • new desuperheaters to increase pipe capacity and reduce heat loss
   • new boiler make-up water treatment system components to increase capacity
   • an emergency generator
6. Coal Storage Enclosure

   A new enclosure over the exterior coal yard will reduce fugitive coal dust emissions as well as the run-off of stormwater.

7. Life Sciences Distribution Piping

   New steam and condensate distribution piping will serve new buildings in the Life Sciences portion of campus.

8. North Campus Distribution Piping

   New steam and condensate distribution piping will serve new buildings in the North Campus.

Boiler Pollution Controls

Boiler pollution controls reduce the amount of SO2, a contributor to acid rain, by 80%.

This $5.85 million capital project adds pollution controls (i.e. bag house and scrubber) to Boiler No. 7 to comply with the boiler Maximum Available Control Technology (MACT) legislation. The project is expected to be completed in January 2007. The new bag house can be expected to remove 98+% of the particulates from Boiler No. 7. Based on the 2005 air emissions inventory, particulate emissions from the central steam plant will drop from 41 tons per year (tpy) to 1 tpy. Assuming an 80% removal rate by the new scrubber, the SO2 emissions from Boiler No. 7 drop from 440 tpy to 90 tpy. Based on the 2005 air emissions inventory, total SO2 emissions will decreasse from 460 tpy to 110 tpy.

Chilled Water Utility

The Utility Master Plan recommends that three interconnected chilled water plants serve the campus (four long-term). The past practice of serving new campus facilities with individual building chillers will be discontinued. The new approach is expected to result save $40 million over the next 20 years.

• Existing North Campus Chilled Water Plant and System Improvements
  
  The Utilities Master Plan has identified four specific improvement projects that are needed to the north campus chilled water plant and its associated building loop system. The first three projects include repairs to the existing cooling towers, replacement of the existing distribution system pumps, and replacement of the last university large chiller no. one (1220 tons) that is operating on CFC-11. CFC-11 has been identified as contributing to the depletion of the earth’s ozone layer. Replacement of this chiller with new technology will allow for all new buildings and/or building renovation projects to be capable of achieving LEED certification. These three projects, combined with the low delta-T correction initiative described below will significantly increase the north campus chilled water system operational efficiency as well as allow this system to serve new loads in this part of campus by allowing the full output capacity of this plant to be realized.
  
  
• Low delta-T correction initiative
  
  Facilities has initiated a pilot project underway at Williams Hall and McBryde Hall where Facilities will measure the water flow in the chilled water system of these two buildings. Many of our buildings on the north campus chilled water loop utilize three-way valves to control chilled water through the building coils to provide conditioned air to the facilities. The three-way valves regulate the water flow through the coils by allowing unneeded chilled water to by-pass the coils. The unused water is then returned to the chiller plant. This process works well at the building level but greatly increases the pumping requirements of the entire chilled water system. The increased pumping requirements under this system utilize power and energy that would otherwise not be required. By installing a variable pumping arrangement within the building system, the new system would only allow the needed chilled water to be pumped through the building coils while the remaining chilled water that was previously by-passed around the coils would remain in the chilled water supply piping. This arrangement will greatly reduce the amount of water being pumped through the entire system resulting in considerable energy savings. This pilot project would quantify those savings which would then be calculated to show the savings that could result from updating all the buildings connected to the north campus chilled water plant.

Water Audit Results

New water conserving fixtures are one result of the Water Audit.

Facilities initiated the campus-wide Water Audit using the Energy Efficiency and Operational Performance Contracting Act. A project team was formed comprising stakeholders from Facilities, all Auxiliaries, and the Budget Office. The study was completed in April 2005 and the results were promptly provided to all stakeholders. The study identified approximately $322,000 in annual water and sewer savings for both E&G and Auxiliaries if approximately $2.2 million were invested in the various water conservation measures identified in the report. The identified savings represent a 14.3% Return-on-Investment (ROI). Facilities is currently proceeding with a pilot project to replace the toilets, urinals, and faucets in McBryde and Pamplin Halls, and the Sterrett Facilities Complex for an approximate cost of $120,000.