City of Knoxville LED Streetlight Retrofit

Sustainability Director

Erin Gill
(865) 215-4430

400 Main St., Room 503
Knoxville, TN 37902

  • Share on Facebook
  • Share on Twitter
  • Share on Google+
  • Share via Email
The City of Knoxville spends approximately $4 million each year to cover the energy, operations, and maintenance costs associated with the city's approximately 29,500+ high pressure sodium (HPS) street lights. By converting these HPS lights to modern light emitting diode (LED) technology, the City anticipates achieving significant savings as a result of reduced energy consumption and reduced maintenance costs. Other benefits include:

• Improved light quality, including a reduction in light pollution and improved safety;
• Greater reliability, and fewer outages, sustained by a 10 year luminaire warranty;
• No disposal hazards;
• Greenhouse gas emissions savings, helping the City achieve its goal of reducing municipal greenhouse gas emissions 20% by 2020.


LED lights vs High Pressure Sodium lights


The City has contracted with Siemens to provide turn-key design and installation services for the LED project. The scope of work for the contract will include three phases, summarized below. Full descriptions may be found in the RFP.

1. Phase One: Project Development
a. Review and Update Streetlight Inventory
b. Complete Photometric Analysis
c. Assess Rebate Eligibility & Billing
d. Develop Initial Replacement Plan
e. Test Deployment for Stakeholder Input
f. Confirm Replacement Plan
g. Secure All Necessary Approvals

2. Phase Two: Project Implementation
a. Purchase Materials/Manage Deliveries
b. Community Outreach/Awareness
c. Obtain Traffic Control Permits
d. Installation of New Lights
e. Removal and Disposal of Old Lights
f. Inspect Work/Correct Punch List
g. Test Lights
h. Recommend Clean Schedule
i. Provide 1-800 Telephone/Online Input Options
j. Ensure Data Compatibility

3. Phase Three: Project Completion
a. Produce Final Project Reporting
b. Process/Receive Applicable Rebates
c. Reconcile Ongoing Billing
d. Provide As Built Documents
e. Provide 1-800 Telephone/Online Input Options

Phase 1 for the project will begin in 2017, and will include an extensive design phase that includes test/demo installations of new lights for evaluation by the City and public stakeholders. During the design phase, there will be multiple opportunities through public meetings and the demonstration installation for local residents and businesses to review and comment on the new proposed lighting. Additionally, project staff can be available to discuss the project and LED lighting plans with neighborhoods and other community groups. 

Once the design phase is complete, Siemens expects to begin installation of new lights across the city in late 2017 or early 2018. According to the contract terms, all work is expected to be complete by June 30, 2019. 


The following table provides a “snapshot” summary of the City's current (pre-retrofit) bill:

Estimated Current Annual Street Lighting Costs (Paid to KUB)
Bill Component Amount Calculation Notes
Energy Charge $ 1,995,484 27,305,476 kWh @ $0.07308/kWh
Facilities Charge $ 1,993,407 $13,795,205 * 14.45%
Glassware $ 30,000 Actual cost for replacement lamps and glassware
Total Annual Bill $ 4,018,891  

Concurrent with the design of the new LED lights, the City will also work with KUB to arrange to reimburse the utility for approximately $5,155,000 million of past infrastructure investments in the lighting system. This reimbursement will eliminate Facilities Charges and minimize maintenance costs going forward. 

The City estimates that the total cost for this project – including the approximately $5,155,000 payment to KUB – will be approximately $15 million . This includes the "turnkey" price of conversion, including (but not limited to) labor, materials, supplies, equipment, facilities, disposal, retrofit design, and processing for all utility rebates. One of the City’s primary objectives is that the cumulative cost savings resulting from the project offset all upfront capital costs (including any financing costs) within 10 years of project commencement.

Based on industry research and experiences in other cities, the City fully anticipates that the retrofit project will achieve the desired payback. The equivalent replacement LED luminaires are expected to use 50-60% less energy than the existing HPS lights, yielding annual savings of $1 million to $1.2 million in reduced energy charges. Additionally, given the 10 year warranties now offered routinely by LED manufacturers and the very low failure rates among the early adopters of LED street lights, the City anticipates significant reduction in maintenance costs. The City anticipates that maintenance costs will fall about 50% below the current Facilities Charge of nearly $2 million.


The City selected Siemens through a competitive procurement process that began in fall 2016.

The City issued a Request for Qualifications on October 26, 2016 inviting interested entities to submit statements of qualifications to substantiate their demonstrated experience and qualifications with regard to completing large scale street light replacement projects and their demonstrated capability of having successfully completed projects of similar size and scope. An evaluation committee reviewed the qualifications and selected qualified finalists to invite to respond to a Request for Proposals (RFP). The RFP was issued to finalists on January 9, 2017 and requested detailed proposals in which, among other things, firms described how they planned to accomplish the project, the luminaires they proposed to use, and their cost for the project as well as any optional pricing that may be desired by the City.


The City worked with KUB and other partners to develop minimum specifications for LED luminaires, drivers, performance/safety standards, and maintenance that reflect industry specifications and best practices for LED technology. In the RFP, the City did not specify a particular brand or model of LED luminaire, but rather requested that submitters propose specific luminaires that comply with the minimum specifications, are listed on the DesignLights Consortium (DLC) Qualified Products List, and which (in the proposer’s view) best meet the City's objectives for this project.

The City's RFP requires firms to provide a minimum ten (10) year warranty for all components of the luminaire, including drivers (power supplies) and a ten (10) year warranty on finish and materials. In addition, firms shall provide a minimum twelve (12) Year Hardware Warranty for 20-year rated life photo cells, and shall provide a labor warranty for two (2) years from the date of project acceptance.

One of the primary design considerations of concern to the City is the ability of the new LED system to meet or exceed existing lighting levels, with a goal of achieving ANSI/IES RP-8-14 where practical. To address this concern, the City's selected contractor must perform and deliver photometric analyses (stamped by a professional engineer) to verify existing conditions and confirm that proposed luminaires will meet or exceed the current lighting levels.

The City also desired to follow to the extent practicable the guidance of both the American Medical Association (AMA) and the International Dark Skies Alliance. Following this guidance, the City included minimum technical specifications requiring new LED luminaires to have a correlated color temperature of 3,000K nominal CCT (+/- 500), subject to proposed design that results in improved public safety with streets not under- or over- lit, improved color rendering, more consistent light levels and heightened detection distance. In addition, luminaires and housing must be fully shielded and installed in such a way that no light is emitted above a horizontal plane running through the lowest part of the fixture. Luminaires and housing shall also accommodate optional field-installed backlight control shields. Proposing firms were asked to describe how proposed luminaires – and the proposed approach to design – will adhere to the guidelines and best practices issued by the International Dark Skies Alliance, American Medical Association, and the Illuminating Engineering Society of North America.