Project Purpose

To build a 125 megawatt (MW), utility-scale solar energy project in collaboration with partners that will provide 100 MW of clean energy to power Metropolitan Government of Nashville (Metro-Nashville) facilities and advance the city over one-third of the way toward supplying 100% of Metro-Nashville’s operations with renewable energy by 2041.

Project Overview

In November 2020, Nashville Mayor John Cooper announced a partnership with Vanderbilt University, Nashville Electric Service (NES), and the Tennessee Valley Authority (TVA) to construct a 125 MW utility-scale solar array as part of TVA’s Green Invest program. The deal allocates 100 MW of the energy generated from the array to Metro-Nashville, and 25 MW to co-subscriber Vanderbilt University. Metro-Nashville will be the first local government in TVA’s service territory to participate in the Green Invest program, contributing to a broader, growing trend of cities using utility green tariff programs to acquire renewable energy.

The Green Invest program uses a public-private partnership model, where TVA pairs its larger renewable energy customers with solar developers through a competitive bid process. In this case, TVA contracted with solar developer Silicon Ranch Corporation, on behalf of both Metro-Nashville and Vanderbilt University, to build 125 MW of solar infrastructure in Tullahoma, Tennessee. Construction is expected to be completed and the array operational by fall 2023.

This project is one of the largest municipal renewable energy deals ever completed in the Southeastern United States. Nashville’s share of the energy generated is enough to power over 11,000 households annually, while also reducing the city’s carbon emissions by an amount equivalent to removing 14,166 cars from the road each year for the duration of the 20-year agreement. As the first local government to participate in Green Invest, Metro-Nashville hopes to help scale up the availability of renewable energy more broadly in TVA territory. In addition, it seeks to encourage large customers in both the public and private sectors, particularly other municipalities, to follow Metro-Nashville’s lead and pursue access to utility-scale solar through the program.

In April 2021, the solar project gained additional co-subscribers when Jack Daniels Distillery signed on for 20 MW and the Knoxville Utilities Board finalized a deal for 55 MW. Combined with Metro-Nashville’s 100 MW subscription and Vanderbilt University’s 25 MW subscription, the full 200 MW facility is to be the largest solar project ever announced in the state of Tennessee.

How was the deal structured?

TVA’s Green Invest program is offered as a green tariff, where large institutional customers like Metro-Nashville or Vanderbilt University pay an agreed-upon renewable energy credit (REC) fee per megawatt hour (MWh) generated, which is then applied as a surcharge on the customer’s routine, recurring electricity costs. The agreement spans 20 years and since the project will not be operational until 2023, the REC fee will not go into effect until the solar is online and generating electricity. The tariff applied to the customer’s monthly utility bill will vary according to the capacity factor of the array.

What were Nashville’s biggest challenges in setting up this project?

Signing the initial Green Invest agreement: Signing the Green Invest agreement is the first step in being able to participate in the TVA Green Invest program. Doing so allows customers to review potential solar projects that have been vetted by TVA’s technical teams as being compatible with TVA’s grid and otherwise eligible for the Green Invest program. But prior to signing the Green Invest agreement, Metro-Nashville had to first sign a non-disclosure agreement (NDA). Because Metro-Nashville was the first local government to participate, city staff had to work with TVA to modify the NDA to reflect deference to the Tennessee Public Records Act, which took extra time.

Identifying the number of megawatts needed for the project: First, Metro-Nashville needed to identify how many megawatts of energy the city would need to contract for, based upon the specific required benchmarks for carbon-free power in its code-mandated renewable portfolio standard (RPS). This helped determine the scope of the solar development as well as the cost of participating in TVA’s green tariff program. Metro-Nashville Mayor John Cooper decided to sign a 100 MW deal, as it would allow the city to meet and exceed the RPS requirement of achieving 35% renewable energy for city operations by 2025.

Sealing the deal: Signing a 20-year agreement is not an easy task for a municipality, especially when there are multiple parties involved (Metro-Nashville, local utility NES, Vanderbilt University, and TVA). City staff spent many months reviewing project sites, finalizing contractual agreements with the city’s legal and finance staff, and then passing legislation to approve the contract through a 40-member Metropolitan Council as well as the five-member NES Electric Power Board.

What advice would Nashville give other local governments as they pursue climate action projects?

Target innovative projects that benefit from economies of scale: In TVA’s territory, solar projects benefit from an “economies of scale” factor. The Green Invest program emerged as a cost-effective way to pursue access to renewable energy while demonstrating smart stewardship of taxpayer dollars: the more panels and MWs a customer procures under this green tariff framework, the more affordable it becomes.

Be an early adopter and anticipate potential future challenges: Solar projects rely heavily on access to available land, which can often present a challenge. As an early participant in the program, Metro-Nashville secured its spot in what may become a limited pipeline for TVA to pursue utility-scale infrastructure in the future. Sunbelt states like Tennessee are experiencing an economic boom resulting in population and job growth, which is reducing the land available for other uses.

Help your utility partner consider a local government perspective on its programs: If a city’s utility does not have much experience working with public sector customers, city staff should not shy away from offering guidance on how the utility could improve its renewable product offerings. Public sector customers have unique needs to allow them to proceed with a deal that the utility may need help understanding and accounting for.

“Reference check” with other customers that have participated in your utility’s program: Metro-Nashville was able to consult with other private sector entities in TVA’s service territory that had participated in the Green Invest program. Some of these participants had helped pioneer the program’s initial availability years ago by working with TVA to structure a formal product offering for large Valley customers. The catalytic push from large, private-sector customers—namely Google, Facebook, and Vanderbilt University—established the legal and operational framework for a novel green tariff program in TVA territory. Other large public and private sector organizations can now access this program to help advance their own climate and decarbonization goals.

How does this project fit into Nashville’s broader climate and community goals?

The Energy Subcommittee of Mayor John Cooper’s 50-member Sustainability Advisory Committee recommended that Nashville achieve an 80% reduction in both community-wide and municipal greenhouse gas emissions by 2050. Signing onto the TVA Green Invest solar project puts Nashville over a third of the way toward powering 100% of its municipal operations with renewable energy by 2041. It also enables the City to meet its code-mandated renewable portfolio standard to procure 35% of its energy from renewable sources by 2025. (The project also enables Vanderbilt to reach its 100% renewable energy target.)

Over the course of the 20-year agreement, Nashville’s 100 MW share of the energy generated is enough to power over 11,000 households annually, while also reducing the City’s carbon emissions by an amount equivalent to removing 14,166 cars from the road each year for the duration of the agreement. In addition, construction of the full 200 MW array will create an estimated 500 jobs and resulting reductions in harmful air pollution are expected to save $3 million to $6.8 million in health costs for regional communities. 

Using the Green Invest program to access solar power enables Metro-Nashville to affordably exceed some of its interim renewable power benchmarks set out in legislation codifying its RPS. The project will allow Nashville to meet its 2025 RPS requirements at a cost of less than 0.7% added onto the City’s current electricity bills. Metro plans to help neutralize this cost by investing in energy-efficiency retrofits of its older public buildings. Nashville has also laid the contractual groundwork with TVA to pursue additional Green Invest transactions, beyond 2023, in order to meet its future RPS requirements for renewable energy procurement.  

Additional Information and Resources

• Mayor Cooper Announces Partnership to Construct 100 Megawatts of Solar Energy in Middle Tennessee (Metro-Nashville press release)
• Vanderbilt and Nashville Undertake Bold New Renewable Energy Partnership to Address Climate Change (Vanderbilt University press release)
• Bill BL2019-1600 (City of Nashville renewable energy portfolio standard)
• Green Invest program (Tennessee Valley Authority’s program website)
• Metro signs on to solar energy initiative (News article)
• Two Recent Developments Put Nashville on Track for a More Sustainable Future (News article)
• Energy Bill Package in Nashville Could Be a Step to #RenewTN (Southern Alliance for Clean Energy blog)
• A Green New Deal for Nashville? (News article)
• Mayor John Cooper’s Sustainability Advisory Committee Report on Metropolitan Government of Nashville and Davidson County’s Climate Change Mitigation Action Plan (Metro-Nashville report)
• TVA Green Invest legislation (Metro-Nashville contract approval)
• Solar Energy and Capacity Value (NREL fact sheet)
• Green Tariff (Renewables Accelerator’s guidance for this type of procurement)

The Metropolitan Government of Nashville received technical assistance from the American Cities Climate Challenge Renewables Accelerator on this project. This project was included on the Renewables Accelerator’s list: 10 of the Most Noteworthy Local Government Renewables Deals of 2020.