Noise
Expected operational noise levels, comparison to common sounds, distance attenuation, and mitigation measures.
This page follows our Community Right-to-Know commitment
What We Know
Operational Noise Levels
Battery energy storage systems are significantly quieter than traditional power generation facilities. The primary noise sources during operation are:
- HVAC cooling fans on each Megapack unit, which match the volume of a residential air conditioning unit
- Power conversion equipment: inverters and transformers produce a low hum during charge/discharge cycles
How Loud Is It?
For context, here are some everyday sound levels:
| Sound Source | Approximate Level |
|---|---|
| Quiet library | 30 dB |
| Normal conversation | 60 dB |
| Lawn mower | 90 dB |
Where the Sound Study Stands
An earlier version of this page estimated about 40 dB at the nearest property line. We have withdrawn that estimate. A first screening study in September, a preliminary model by the project team that no sound engineer has yet confirmed, found that, with the current layout, the two closest property lines would be louder than the state noise policy allows. It used a stand-in unit because Tesla has not published Megapack 3 sound data. We are testing fixes: quieter fan settings, low-noise transformers, a sound wall, and moving equipment rows. The full study, with predicted levels at property lines and nearby homes, goes in the Document Library when it is finished and is filed with the application to the Energy Facilities Siting Board.
Distance Helps
Sound decreases with distance. The project's setbacks and the distance to neighboring homes provide significant noise attenuation:
- Sound decreases by approximately 6 dB for every doubling of distance
- Terrain shields some homes to the west and south; trees in leaf add only about 1 dB
- Hundreds of feet separate the nearest residences from the BESS area
Built-In Mitigation
Tesla designs the Megapack 3 units with noise-reducing features:
- Enclosed cabinet design containing most sound
- Variable-speed fans that run quieter during low-demand periods
- Sound-dampening materials in the unit construction
What We're Still Studying
- Detailed acoustic study: the September screening study is done; the full study models predicted levels at property lines and nearby homes with the final layout and equipment data
- Nighttime noise levels: we are evaluating whether the facility requires operational adjustments during nighttime hours
- Cumulative noise impact: we are assessing how noise from 136 units interacts across the site
What You Can Influence
- Noise concerns: let us know if noise is a top priority for you through Share Your Voice so we can prioritize additional mitigation measures
- Monitoring requests: suggest locations where we should conduct noise monitoring during operation
- Operating hour preferences: share whether you would value time-of-day restrictions on louder maintenance activities