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Metro Nashville District Energy System Will Provide Steam and Chilled Water for the Music City Center During Construction and for Ongoing Operations

The pipeline design is completed and construction will begin shortly to install the new District Energy System pipelines needed to serve the Music City Center. Steam and Chilled Water services are scheduled to go online next Spring so that DES can serve the facility during project construction, then continue providing ongoing services once the center is fully operational. The new underground distribution system includes a 12” steam line, a 6” condensate return line, and two 24” chilled water lines that extend from the existing distribution system serving the Schermerhorn Symphony Center to the point of entry at the Music City Center on Demonbreun Street.
DES will provide heating and cooling during construction of the Music City Center that otherwise would require temporary services. DES chilled water will provide cooling during the warmer months of the year primarily to remove humidity from the building during construction. During winter months, steam will be used to heat the enclosed areas of the building. DES offers a very good fit with the new environmentally friendly Music City Center both during construction and on an ongoing basis for many reasons including: a reduced carbon footprint when compared to alternative stand alone heating and cooling options, lower capital costs and overall savings on heating and cooling costs for the center, and the aesthetic advantage of not having cooling towers and other stand alone components competing with the overall design of the center.

How did the flood affect the Metro Nashville District Energy System?

On Saturday, May 1, 2010, most everyone in the middle Tennessee area was watching local television coverage of the severe thunderstorm warnings, tornado watches and flood watches. The storms continued throughout the night and all the next day without letting up. Record rainfall was recorded in the Nashville area on both Saturday and Sunday, with more than 6 inches both days. Creeks and rivers flooded neighborhoods, roads and the interstates surrounding Nashville. This made it nearly impossible to navigate to and around the city.
On Sunday afternoon, as the flood waters started spilling over the banks of the Cumberland River in downtown Nashville, DES' steam system was shut down to avoid potential safety issues, such as water hammers.
Sunday night, water spilled onto First Avenue, filling the energy distribution tunnels on
Broadway.
By Monday night, the river finally crested. Water reached as far as the Country Music Hall of
Fame on Fourth Avenue.
During this time, the Energy Generation Facility was never in jeopardy of being flooded, as the chilled water system continued to supply cooling to the DES customers.
When the water receded and the operators of the DES were allowed access to the area, approximately 800,000 gallons of water were pumped out of the tunnels over the next two and a half days. After all structures, piping, insulation and electrical components were inspected, boilers were lit at the Energy Generation Facility to restore steam service to the DES customers. Condensate in the steam lines had to be evacuated slowly, and the wet insulation had to be dried as the system came up to operating pressure. At approximately 7 p.m. on Saturday, May 8, the steam system was back to normal.
The following statement was issued by the Metro DES liaison: "We greatly appreciate the outstanding work of CEPS (Constellation Energy Projects & Services Group) in working to restore service to district energy system customers in very difficult conditions. A job 'very well done' is extended to the staff and crew for their dedicated efforts."

Michael Bradley Retires

Michael Bradley has served as the Metro liaison to the Nashville District Energy System for the past six years. After more than 40 years of service in state and local government, Bradley made the decision to retire from Metro Government effective March 31, 2010.
He was recently honored for his dedication to Nashville and its citizens. In a certificate of recognition, Mayor Karl Dean cited Bradley's contributions to the economic development of the downtown district through his work as liaison for the Metro Nashville District Energy System.
Bradley's past government experience includes work with the Metro Department of Children's Services, Metro Finance and Real Property Services, Tennessee Department of Mental Health, and the Tennessee Board of Probation and Parole, where he served as executive director.
Bradley plans to use his experience to continue his career in the nonprofit sector. He has been a valuable asset to district energy in Nashville, and we wish him well in his future endeavors.

Tunnel Rehab Project Underway

A series of tunnels exist beneath the streets of Nashville through which NDES distributes steam, condensate and chilled water to customers. These tunnels were constructed 25+ years ago and were bored through solid rock. Due primarily to ground water seepage, numerous locations exist within the tunnels where rock in the upper portions of the tunnel has loosened and require repair. NDES will spend over $1,000,000 to make repairs and thus preserve the tunnel system integrity for many years to come.

 

 

Milder Summer Temperatures and Lower Winter Fuel Costs Should Result in Back to Back Seasons of Savings for DES Customers

The Summer of 2009 resulted in lower usage from the District Energy Plant for chilled water due primarily to milder temperatures through the hot months of summer. Consumption for chilled water was lower by an aggregate average of 13% among all DES customers. Summer plant operations were also more efficient (1.5.% greater efficiency than the prior year) resulting in costs savings that are shared by DES customers. Private customers realized the greatest average cost reductions at just over 7% savings compared to the prior year.

Cooling degree days were 18% lower than the previous summer and there were fewer extremes in temperature fluctuations–both are likely reasons behind the improvement in efficiency.

The DES plant chillers run most efficiently at 75%-90% of their load capacity. Continuously operating the chillers within this range results in optimal efficiency. The DES is professionally operated, maintained, monitored, and supervised to ensure optimal performance.

Lower Natural Gas Prices for the Coming Winters

Lower fuel costs for this winter should result in good news for DES customers as well. Boilers at the DES plant burn natural gas to create steam. Lower national demand for natural gas from the industrial sector has led to lower gas prices in the comedies market this fall and winter. Natural gas is purchased for use at the DES plant using a combination of futures contracts and spot market pricing. The reduction in gas prices have allowed fuel to be purchased to cover a significant portion of this winter’s demand. Together with the anticipated low cost for the balance of the gas required should result in actual fuel costs to be two-thirds of the budgeted price for fuel.

As long as pricing continues to be weak, DES will continue purchasing natural gas on the spot market to maximize fuel savings. And because all savings are passed through to the DES customer, the variable cost portion of their bills should result in lower costs this winter.

Mayor Karl Dean Presented Certificates of Appreciation to Three Former Board Members

The Metro Nashville District Energy System Advisory Board was established in 2004 to review DES activities and make reports and recommendations to the mayor's office. Prior to the November 19, 2009, board meeting, current board chairwoman Karen Bennett introduced Mayor Karl Dean in an informal ceremony to recognize three former DES board members. Mayor Dean thanked Joe Sweat, J.B. Loring and Charles Harrison for their dedication and service. Each of the honorees was then presented a certificate of recognition.

Charles Harrison earned his Bachelor of Science degree from the University of Tennessee, where he majored in accounting. Harrison is a licensed Certified Public Accountant and is a Certified Government Financial Manager. He served as the assistant to the state's Comptroller of the Treasury from 1985 to 2009. In that position, he was directly involved with the financial management of state projects and contracts, provided accounting, budgeting, information systems and human resources support to the Office of the Comptroller, and advised state departments regarding procurement and contracting issues.

In 2009, Governor Phil Bredesen named Harrison as Special Assistant to the Governor for Recovery Act Administration to lead the state's implementation of the American Recovery and Reinvestment Act of 2009. Harrison decided to retire rather than to accept this new position.

Prior to his retirement, he was a member of the Association of Government Accountants, where he served as a national president. He was also appointed as the State Constitutional Officers' representative to the UT Foundations Study Committee and was the state's representative on the Metropolitan Nashville District Energy System Advisory Board. With his extensive accounting background, he was committed to helping the DES Advisory Board ensure dependable and cost-effective services were provided to the DES customers.

"Nashville's downtown business district is very fortunate to have a world-class district energy facility dedicated to providing efficient and cost-effective energy to our buildings," Harrison said. Harrison has a long history with district energy in Nashville. Prior to becoming a DES Advisory Board member, he served on the board of directors for Nashville Thermal Transfer Corporation.

J.B. Loring, a Nashville native, attended the University of Tennessee, where he received his pre-law degree. He later attended Nashville School of Law, where he received his Doctor of Jurisprudence degree.

Loring served in the U.S. Coast Guard for three years and in the U.S. Air Force for two years; he was stationed in Korea during the Korean War. He is a life member of the Korean War Veterans Association, the American Legion and the Veterans of Foreign Wars. He spent 30 years with Nashville Electric Service before retiring as director.

Loring is also a former Metro Council member. He represented District 15 in the Donelson area. His vast experience, coupled with his background in government and the energy business, made him a perfect candidate for the DES board. He served as a board member, representing Metro, for many years and was a past chairman. Loring also served on the board of directors for Nashville Thermal Transfer Corporation.

Joe Sweat earned a degree in English literature from the University of Memphis. He is a member of the national board of directors and national executive committee for the ACLU. He also serves on the board of directors and as a volunteer lobbyist for ACLU Tennessee.

Sweat is a U.S. Navy veteran and also has an extensive background in journalism. He covered politics, civil rights and the music industry for The Associated Press, was an urban affairs writer for The Commercial Appeal, organized and directed the Vanderbilt University News Bureau and continues to contribute articles to the Nashville Scene. Sweat is also a former Society of Professional Journalists member and was the lead reporter covering the death of Martin Luther King Jr. for The Commercial Appeal.

Sweat served as the executive director of the Tennessee Municipal League from 1982 to 1998. He is also an immediate past member of the Metro Nashville District Energy Board and the Metro Nashville Planning Commission. With an extensive knowledge of Nashville's Metro government, Sweat was a valuable asset for the Metro Nashville District Energy Board.

Deaderick Street Projects

During the fall of 2008, NDES became aware of the Department of Public Works’ Streetscape project for Deaderick Street.  This Streetscape Project involves the refurbishment and revitalization of the Streetscape along Deaderick Street between 3rd Avenue North and 6th Avenue North.  This Streetscape Project began construction during the fall of 2008 and the Department of Public Works notified all underground utilities that if work was required within the Deaerick Street boundaries, it need to take place right away and not impact the schedule of the Streetscape Project which was scheduled for completion during the summer of 2009.  NDES had four projects that fell within the boundaries of the Streetscape Project:

These projects were completed in the first three months of 2009 so there was no negative impact to the Streetscape Project.

Ryman Auditorium Project

The condensate service line to the Ryman Auditorium from the main in 4th Avenue was in very poor condition and needed to be replaced.  After analyzing options, it was determined that the replacement of this line could be cost effective.  Therefore, a design for a replacement line was completed and put out to bid.  The pricing received was within the payback parameters so construction began in April of 2009.  With the Annual Country Music Festival beginning in early June, this line replacement needed to occur at a fast pace.  Approximately 290 feet of new 2" was installed by the end of May of 2009 and there wasn’t any conflict with the Music Festival.

Nashville (DES) Underground

The Nashville District Energy System Distribution System is comprised of four primary pipes; chilled water supply, chilled water return, steam supply and condensate return. These pipes account for approximately 84,000 feet of piping contained in four miles of direct-buried trenches or tunnel systems. There are three independent tunnel systems within the distribution system: the main tunnel system which is comprised of the 4th Avenue Tunnel, the 7th Avenue Tunnel and the Broadway Tunnel; the State Tunnel System and the AA Birch Tunnel.

The underground tunnel piping and all of the manhole piping is inspected on a monthly basis to ensure timely repairs are made in order to maintain the overall system performance and efficiency.

The construction of these tunnel systems minimized the impact on traffic and businesses in the downtown area during the installation of the piping systems as opposed to a conventional open-trench, direct buried construction. In addition, the tunnel systems provide a means of inspecting and maintaining the piping systems on a regular basis that is not afforded by the direct buried method.

Customer Fixed Charges To Remain Flat for FY2010

Before the beginning of each fiscal, DES customer charges tied to the fixed costs for system operations are adjusted upward for inflation per the steam service agreement based on changes in the Consumer Price Index (CPI). As a result of the current CPI turning negative, there will be no upward adjustments of customer fixed charges for FY2010.