Open House FAQs

County of Sonoma Regulations / Entitlement Process / CEQA /EIR

Is an EIR required for this project?

The California Environmental Quality Act (CEQA) specifies that only the lead agency, in this case the County of Sonoma, decides what level of CEQA study must be prepared. The County is in the process of making this decision.

What is the estimated timeline of this project?

Operations are estimated to start in 2025.

How many trees will be removed?

We estimate 12 trees will be removed from the existing wind row, located between the project site and the Lakeville substation to comply with PG&E vegetation clearance requirements. Approximately 50 existing trees on the project site of varying species, dimensions and health will also be removed. Landscaping around the project site will include planting approximately 200 new mature trees in addition to shrubs, perennials, and groundcover. The project complies with Sonoma County’s Tree Preservation Ordinance.

Does the City of Petaluma have any input in these approvals?

This project is in the unincorporated area of Sonoma County. Therefore, Sonoma County is the government agency that processes and considers Strata’s applications.

How does the existing open space easement affect the project?

There is a “Grant of Open Space Easement” on the project site, which was recorded on September 6, 1990. This easement is with Sonoma County and pre-dates the Sonoma County Agricultural Preservation and Open Space District, which was created via Measures A and C in November of 1990, and is funded with one-quarter percent of sales tax revenue. The easement on the project site is materially different from modern easements that the Open Space District uses. No public funds were used to acquire or maintain the easement on the project site.

If housing expanded into the area on the golf course how will you maintain a ¼ mile buffer from residences?

No housing is proposed as part of the battery storage project. The golf course has recreational, or “K” Zoning. In the K zoning district, almost any residential use requires a conditional use permit and a public approval process. Housing is not part of this project and is not reasonably foreseeable as part of the battery storage project. Thus, any future housing is speculative.

Why does this project have to be located here and not further in the country area?

A battery storage unit performs best and allows the owner to provide the lowest cost to the rate payers when it is close to a substation. Proximity to a substation is a critical factor for grid connection costs, space required for the project, and minimizing transmission losses. As projects move farther away from substations, they lose more energy in the transmission process, require more land for additional on-site substation facilities, may be economically infeasible, and require additional overhead lines which generate visual and land impacts that are not present when a project is adjacent to a substation.

Was the flight path a consideration during this process?

Yes. Sonoma County’s Airport Land Use Commission found the project is consistent with Petaluma Airport’s safety zones established by the Comprehensive Airport Land Use Plan. In making this finding, the Commission confirmed with the Fire Marshal that the proposed project does not involve hazardous materials or storage of explosive or flammable materials so long as it complies with all building and fire code requirements. The Commission further found that the proposed project is not a “noise sensitive use” and does not require special measures to offset aircraft-generated noise. Finally, the Commission found the project will not be illuminated as part of normal operations, thus it will not interfere with aircraft take off or landings.

What does the FAA say about this plan not the local jurisdiction?

The FAA determined would not be a hazard to air navigation and submitted that determination to the county.

Who certifies that the facility meets all the requirements and was built correctly?

Sonoma County inspectors are responsible for inspecting the project and certifying that it complies with building, electrical, and fire codes. In addition, projects that require long term investments such as this one typically have an independent owner’s engineer who inspects the installation to ensure that the project will operate as intended.

Do you comply with Sonoma County’s noise ordinance?

Yes. Sonoma County has nighttime and daytime noise limits, and the project will comply with both. The project also complies with the City of Petaluma’s noise limits, even though it is not required.

Project Funding

Is PG&E paying for this project?

No, Strata is an independent power producer and private company. Strata will pay for the project, interconnection facilities, and grid upgrades, and will contract the services this project provides to the grid with various load serving entities in California (e.g., community choice aggregator, utility, and/or private power provider).

What is your business with PG&E?

We are electrically connecting to a PG&E facility and have an agreement with PG&E to pay PG&E for completing upgrades to its substation necessary for the project to connect.

Who is paying for the A/C units cooling the batteries to be powered 24 hours a day?

Strata pays for all costs associated with operating the facility. The facility will have an electric meter just like any other commercial operation and will be billed by PG&E for energy usage.

Battery Function / Solar Capture / Use of Stored Power / Power Grid

Where does the power come from to operate these battery units?

The energy required to charge the batteries and operate the project comes from the electrical grid.

What happens when the batteries off load power back to the grid?

The discharged energy goes to the electric grid.

Are you providing energy to Sonoma Clean Power?

We have discussed this project with Sonoma Clean Power.

How do you know if the energy being stored is solar?

We have no way to know what type of energy is being used to charge our project. However, most of the time, our project will be charging during the brightest hours of the day and discharging in the evening, after sunset. As such, the net effect is “shifting” cheap, clean, and plentiful solar generation from mid-day to the evening which displaces more costly and dirtier fossil fuel generation.

Is there a public safety power shutoff (PSPS) event offset?

Due to the variety of reasons that may trigger a PSPS, we cannot guarantee that the addition of this project will noticeably reduce local PSPS events; however, this project (and others like it) individually and collectively improve the reliability and resiliency of the power grid which help reduce the severity and/or duration of PSPS events in the state.

What happens when you create solar energy? Is my net energy metering (NEM) devalued?

This project is only an energy storage facility and does not include solar generation. The project will not impact any NEM contract already in effect. Since NEM is effectively a program that allows a residential solar systems to use the grid as a “battery” for residential solar generation, our project helps enact NEM policies (i.e., the project batteries can charge from excess residential solar energy and discharge when needed by the power grid) .

As a residential solar owner, would there be any impact to any amps?

No. This project connects to the grid at the transmission scale and will not affect any residential contracts.

Are you contracted to provide any specific amount of power back to the grid?

No. A typical contract will require us to be online and supporting the grid during peak demand. These types of projects also allow the grid operators to keep the local area energized during Public Safety Power Shut-off (PSPS) events. During a PSPS event, PG&E will shut off certain circuits. The Lakeville substation, if dispatched by PG&E to do so, would be able to discharge locally stored energy to the local area while circuits in the larger grid are closed.

How does the cooling system work?

The air-cooling system works exactly like the air conditioning unit on your home, RV, or any business/building in the area.

What is involved with the venting system and gases being released? Are there gases being released all day long or only when the system gets to a certain temperature?

No, gases are released during the normal operation of the system. If cells overheat, they are designed with safety vents that open releasing minimal amounts of gases including hydrogen, carbon monoxide, carbon dioxide, and various gaseous hydrocarbons (e.g., methane, ethane, and ethylene). The equipment enclosure includes gas detection equipment as well as active and passive ventilation measures that are designed to safely expel such gases from the equipment enclosure.

Battery Manufacturing and Composition / Battery Safety / Recycling

What specific type of lithium-ion battery will be used in this project?

This project will use lithium iron phosphate (LFP) batteries.

What type of phosphate will be used in the batteries?

The phosphate-based cathode chemistry to be used is FeLiPO4.

We heard that the project would be using the earlier technology which some believe is more dangerous than the lithium-iron-phosphate technology. Is that true?

No, that is incorrect. Earlier energy storage projects often used cobalt based chemistries (e.g., nickel manganese cobalt – “NMC” or nickel cobalt aluminum – “NCA”), which are still widely used in electric vehicles and residential energy storage systems. Strata, as well as most other utility-scale energy storage companies now predominantly use lithium iron phosphate (LFP) batteries which are more thermally stable than NMC or NCA chemistries.

Are there drawbacks to using lithium iron phosphate (LFP)?

LFP batteries are less energy dense, so they require more land than cobalt-based chemistries. However, this tradeoff is worth it due to their relatively higher thermal stability than cobalt-based chemistries.

What is the lifespan of each battery?

The current lifespan for lithium-ion batteries like ours operating on the California power grid is 20 years.

Where are your batteries made?

Most top-tier lithium-ion batteries for stationary energy storage applications are manufactured in China. All lithium-ion batteries made for deployment in the US market (regardless of where they are made) must go through rigorous testing, based on codes and standards at the state and federal level, to assure their safety and endurance. Prior to receiving our building permits, test results and certifications for the batteries must be reviewed and approved by local regulators, including the fire department.

If new technology comes out in 5 years that is safer and more effective, will Strata replace the units with the new technology?

Strata would continue to operate the facility using the existing technologyit is already safe and effective.

What is the process when the life of the batteries end?

The site is decommissioned. Decommissioning means removing all Project equipment and improvements from the Project site and restoring the site to pre-construction (or better) conditions. The batteries are sent to an approved recycling facility to be deconstructed and recycled. Recovered materials are re-used in new batteries.

Is the frequent charging and discharging of batteries safe?

Yes, the system is designed to charge and discharge up to two times per day; however, the average battery storage facility in California currently discharges about 0.5 times per day, and this project is expected to discharge less than one time per day on average.

How are you planning to dispose of the batteries?

At the end of the project’s life, the site is decommissioned, and the batteries are sent to an approved recycling facility to be deconstructed and recycled. Recovered materials are re-used in new batteries.

Fire Department / Fire Safety

Do you depend on the Fire Department of Petaluma?

The Rancho Adobe Fire District in unincorporated Sonoma County is the primary responder for the project site. If there is an incident at the site, mutual aid agreements will result in the closest fire apparatus being dispatched to the site. It is possible the City of Petaluma Fire Department would be the first arriving fire agency.

Is the project going to be monitored by a monitor or fire panel?

Both. The project will be monitored 24/7 by an automated on-site system. The project will also be monitored 24/7 by live remote systems administrators. There will also be local operations and maintenance staff who routinely check the site for issues. If any one of these three systems/persons finds an issue that could present a danger, the appropriate fire department will be notified.

Before the system goes online, is there going to be a testing period to vet contracted people such as a simulation for them to see what kind of response time and the response?

The County of Sonoma will not approve operations to begin until the county’s inspectors sign off on the facility. Once the equipment is fully installed on site, the facility must go through a commissioning phase where it is slowly energized and is monitored and tested per various codes and standards required by state and federal laws. Local first responders will be trained in how to respond if there is an incident at Strata’s expense.

Is there a risk of explosion?

The systems are engineered and rigorously tested to virtually eliminate any risk of explosion as required by the National Fire Protection Association and California Fire Code. Systems must be designed and certified to prevent the buildup of gases and thus eliminate the potential for explosions before they can be approved for installation.

If a fire happens, how long will it burn?

The systems are engineered to contain a fire to a single cabinet. A fire typically burns out in 3-12 hours.

What specific training is needed for our local firefighters to put these kinds of fires out?

Firefighters receive extensive training on specialty fires. Strata will work with the local first responders and national experts to develop a training and education plan for this specific site. The plan will include information about equipment on the site, the location of access points for emergency vehicles, emergency water supply, and training on tactics and strategies for how to manage a potential fire.

How will you ensure new firefighters get that training? How often will you do local training?

In addition to daily training built into fire agencies’ normal schedule, there will be annual training, as required by national standards, that local firefighters will be invited to attend.

Lithium-Ion fires are extremely tenacious fires. How can we be sure that the first responders who respond to the incident have had the training? Especially if they’re newly hired, or if only certain first responders get to go to the training.

Only fire agencies can determine how best to ensure their responders are adequately trained. The fire department will have the option to send members to Strata’s annual trainings. Along with the training, Strata will make the training materials readily available to any fire agency that would like a copy. The project will also include an on-site, secure lock box that will contain critical information on the site and operation of the equipment. The box will contain items like a site plan, water supply information, emergency contacts, Material Safety Data Sheets, and current battery information.

Will the fire department have to purchase any special gear to fight these fires?

Currently there is no special equipment necessary for first responders to a battery facility. If a fire agency indicates that some type of special equipment is critical for this facility, Strata will certainly be open to discussing it further.

When there is a fire, who decides which action to take, for example, to let it burn or flood it with water?

This is the fire department’s decision. It is Strata’s responsibility to provide fire agencies with safety information about the site and inform them about industry best practices, but, as the fire professionals, only the fire department makes the final call.

What are the risks involved with flooding the rest of the system?

Flooding a cabinet that is burning will cool the batteries down and scrub smoke and gases, but is generally does not stop the chemical reaction in the battery cells that is causing the fire. As long as the flooding is contained to the cabinet that is burning, as it is designed to do in modern systems, there are no additional risks.

What size water tanks will be on site?

The two proposed tanks are 90,000 gal each. The tanks will be installed if determined necessary by the fire department. The fire department may decide that this much stored water is not necessary to defend the site and surrounding area depending on the availability of water from other sources.

What firefighting equipment is on site right now?

There is an existing fire hydrant currently on the site.

What firefighting equipment will be on site after construction?

Fire hydrants will be added throughout the site so that the fire department can reach the entire site given their standard hose pull lengths.

When a fire happens, where will the runoff water from water suppression go? Are there going to be drains around the site, or somewhere that catches that water?

Industry best practices suggest that water should not be applied to the burning area. If water is applied, the run-off will be captured on-site in proposed stormwater facilities. It will be removed and treated. Studies on lithium-ion fire water runoff have shown that it is similar to that of a structure fire.

Tesla says that their firefighting is proprietary so they won’t share that, will Strata take a similar stance?

No. The equipment installed at the site will all be tested and certified to meet applicable state and national fire safety standards for battery storage facilities. These documents will be shared with the county and local first responders. In addition, Strata will develop project-specific training for the first responders in the area. While certain trade secrets associated with a fire systems design may be proprietary, nothing will be held back from first responders about firefighting mechanisms or plans.

Compare and contrast the gases being put into the environment from a house fire vs. the gases being put in the environment from a battery at this project burning.

The gases and smoke emitted from a battery fire have been analyzed and found to be similar to a typical residential fire or burning a bag of trash.

How would you compare a home electric car charger to this system in terms of likelihood of starting a fire?

Battery energy storage systems (BESS) have been shown, through use, to be less likely to catch fire relative to a home electric car charger. A BESS is also more likely to contain any fire because they are installed outdoors in an isolated environment.

Can the fire that happened to the Tesla battery facility in Victoria, Australia happen here?

This incident was the result of a Tesla defect which has since been fixed. Details of this incident are publicly available from the Australian government. See, for example, this report of technical findings.

Geological / Earthquake Safety

There are multiple fault lines in this neighborhood. Sometimes a 6.0 earthquake is more destructive than an 8.0. Has this system been tested with multiple fault lines?

Seismic design of equipment is primarily a function of acceleration/deceleration associated with earthquakes regardless of how many fault lines there are. The equipment planned for the project is designed to the same types of electric industry seismic standards as the adjacent substation and can handle the acceleration associated with an 8.0 earthquake as well as a 6.0 earthquake.

Has the earthquake testing on tables been done on acceleration and deceleration on tolerance of the units going up and down versus side-to-side shaking? Since we don’t know the vendor of the batteries yet, how can Strata say with 100% certainty that the enclosures have been shake table tested up to an 8 on the Richter scale?

All infrastructure is designed to meet strict state and federal regulation standards, including for seismic design requirements. It is designed to meet the same standards PG&E’s substation must meet for earthquake tolerance. Adherence to these requirements is verified by county inspectors during construction and if the project doesn’t meet the requirements it cannot operate.

With all the geological and seismic issues in the area, why isn’t the geological study going down deeper than 20 feet to see what soil and liquidity issues are there for earthquake safety?

This project is subject to the same building and safety standards as all other construction in the area. In this area, given the soils encountered, in order to evaluate the foundation design necessary to safely install the battery systems, it is not necessary to drill deeper than 20 feet.

Why don’t they drill down deeper to bedrock?

Civil engineering standards for seismicity (required to be followed by law) dictate what types of foundations we must use. Based on the analysis of the soils and seismicity in the area, drilling to bedrock is not required.

What are all the regulations governing this technology?

Numerous local, state, national and other applicable building, safety, and fire codes are applicable to the design, construction and operation of the North Bay Energy Storage Project, including:

  • Sonoma County Building, Development, and Fire Codes
  • California Fire Code
  • National Electric Code
  • National Fire Protection Association (NFPA) Standards
  • Underwriters Laboratories (UL) Certifications
  • International Electrotechnical Commission Standards

These codes are constantly being updated to improve safety and keep up with changes in the industry. Modern, lithium-ion battery energy storage systems are subject to robust testing and detailed safety standards from recognized authorities such as the NFPA and UL. The most notable standard is UL 9540, which requires compliance with several related codes and analyzes safety of battery energy storage systems. In addition, compliance with NFPA 855 set forth minimum design and safety standards for battery energy storage systems.

When the life of the project is over, will Strata be replacing the units and what kind of approval will it need from the County for replacement?

At the end of the project’s life, the site is decommissioned, and the batteries are sent to an approved recycling facility to be deconstructed and recycled. Recovered materials are re-used in new batteries by the integrator, similar to any other recycling process.

24/7 Monitoring / Cyber Attack / Vandalism

Will there be an onsite technician?

The project does not include an onsite office building; however, there will frequently be technicians onsite, technicians within thirty minutes of the site, and the project will be monitored 24/7/365 by multiple offsite parties.

If monitored remotely, what happens in a cyber-attack? Can someone set off a fire through a cyber-attack?

The project is subject to strict federal cyber security requirements set in place via the North American Electric Reliability Corporation (“NERC”) Critical Infrastructure Protection (“CIP”) standards, so a hacking attack is unlikely. Even if a hacker accessed the battery system, the hacker cannot set off a fire via cyber-attack.

What happens if the homeless get into the site?

If someone were to scale the fence, our monitoring would detect it and law enforcement would be called.

How do you secure perimeter such as issues like vandalism or people shooting at these types of substations?

An 8-foot high fence will be around the facility designed in accordance with North American Electric Reliability Corporation (“NERC”) Critical Infrastructure Protection (“CIP”) physical security standards. The site will also have a berm that blocks the facility from view. The berm and the fence are expected to mitigate the ability of a ground level shooter being able to hit the facility. The site is also monitored and if there is an unauthorized breach authorities will be notified.

Benefits to the Neighbors or Community / Impacts to Home Values or Insurance

What are community members going to gain from this project?

This project will increase the reliability and resilience of the power grid which can help reduce the severity and duration of Public Safety Power Shutoffs (PSPS). This project will also help reduce the carbon intensity of the power grid by shifting the availability of excess solar energy from day to night, offsetting the need for natural gas peaking power plant usage and their associated emissions. The project will also provide significant economic benefits to Sonoma County and the region. Construction jobs, new property tax revenue, and ancillary economic stimulus will be injected into the community during the construction and operations of the facility.

Will my PG&E bill go up?

Contracted costs with independent power producer projects like this one are passed through to rate-payers without utility markup and are typically more cost effective than rate-based projects due to independent power producers leveraging lower costs of capital than utilities have access to. We have no control over what PG&E will charge its customers, but we can provide grid services that help to reduce PG&E’s overall operating costs compared to traditional grid improvement facilities.

Will my home value go down?

The value of your home is comprised of many factors. The overwhelming majority of those will not change based on the installation of a battery energy storage facility operating next to a large substation, hidden from view, and over a quarter mile away from the nearest homes.

Will my home insurance go up?

No. Insurance underwriters are governed by state law which requires insurance companies to view each county as a whole when evaluating risk. Insurance is not underwritten at the neighborhood level.

Strata Company Questions

How many successful facilities does Strata have?

Strata has built over 250 power projects and owns ~160 power projects. These include 10 energy storage facilities (7 of which are operating and 3 of which are in the construction phase).

How large are the facilities that Strata currently operates?

Strata currently operates and maintains over 250 power projects with a combined capacity of approximately 1 GW. Strata operates and manages projects that are similar to size to this project and larger.

Construction Impacts to Neighbors / Adobe Creek

What is the plan while construction is taking place to make it as minimal impact to the neighborhood?

The project is a quarter mile away from the nearest residence and will comply with construction requirements imposed by the County, including but not limited to, limits on construction hours, dust control, and minimizing noise generated by construction equipment.

How is the project handling potential runoff into Adobe Creek? Runoff that could occur during construction, fire suppression or maintaining the berm around the project?

The project is graded to drain away from Adobe Creek, towards Frates Road. As storm water moves across the site it will be managed and treated through swales, bioretention basins, and other storm water best management practices and facilities.

Water / Landscaping

How much water will this project use?

The project will employ low impact irrigation methods to minimize the amount of water required to sustain the landscaping required by the County. The estimated water necessary to support the planned landscaping is about 295,000 gallons per year.

What type of irrigation/water system will be in place to maintain the berm around the project?

The landscape areas will be designed and irrigated consistent with all applicable County requirements. For irrigation water, the project proposes to connect to the existing recycled water line that is already located on the project site. As a secondary option for irrigation water, the project will also have access to the existing groundwater well and former golf course pond located north of the project site.

Golf Course / Open Space

What is the vegetation management plan for the golf course?

The project does not include golf course management.

The Other BESS Project by PG&E Substation on Frates Road

Is the project going in across the street an expansion of this project?

That project is not associated with this project or with Stata Clean Energy.