Grid-Tied Solar

During the 2025 Palisades and Eaton wildfires around LA, myself and many other neighboring communities who were not directly affected by the fire experience extended power shutoffs due to the high winds in the area. During high wind events, SoCal Edison (SCE) (and other utilities) will shut off power preemptively during so-called “public safety power shutoffs” (PSPS) to prevent the start and spread of wildfires. My neighborhood in Ventura County lost power for almost three days.

The ironic thing is that my house, and many other of my neighbors, have solar on the roof with the capability to generate power; however, with the grid down most traditional solar installations will not work. Most standard grid-tied solar installations rely on micro-inverters which convert the DC current from the panel to grid AC to allow you to sell back excess power to the grid. Due to safety issues, when the grid is de-energized the micro-inverters must also shut down to avoid back-feeding power into the grid. I had bought a 1 kWh LFP battery and a 1 kW inverter which allowed us to charge our phones and run our Wifi (which was very fast since a big chunk of our neighborhood was without power), but without any good way to charge the battery at home it eventually ran out.

For most people, grid-tied solar is certainly the cheapest and best option to reduce electricity usage. It may not not pair well in situations with large time of use offsets, such as charging an EV at night, but works great to offset electricity use from AC usage or for powering pool pumps. Most net energy metering (NEM) schemes now no longer pay the residential delivery rate for generated power and instead pay generators at the “super off-peak” rate as residential solar installations generate power during the day when electricity is cheap. Adding a battery and hybrid inverter allows for storage of power, but greatly increases costs. Depending on the size of the system, it may increase the payback period by a factor of 1.25-2x. For emergencies, it may make more sense to purchase one of the portable battery/inverter systems by Ecoflow, Jackery or Bluetti to power necessary electronics and appliances like the fridge and internet routers.

For home owners in SoCal there still might be an advantage to adding an inverter/battery system in addition to roof-top solar. Certainly, with climate change causing wetter wet years and drier dry years, there is a case to be made that grid disruptions will only become more common each year. While getting a gas/dual-fuel inverter generator is the simple and cheap choice, it feels somewhat backwards to buy a gas generator to help offset the disruptions wrought by more severe climate-change exacerbated wildfires. At a state level, with the previous wildfires directly caused by aging infrastructure in NorCal by PG&E, money tasked to tackling worsening wildfires may be better spent in updating aging infrastructure and burying power lines when possible in the wildland-urban interface (WUI). These preemptive power outages are certainly not popular as a whole, ranging from minor inconveniences like having to pitch food in the fridge/freezer to major life disruptions for individuals who need power to run at-home medical equipment. From a macro standpoint, the utility company and communities are better off reimbursing for food spoilage (which you can do at the SCE Claims page) and providing free/discounted hotel stays outside of affected regions for individuals who cannot go without power for more than 2-4+ hours.

The sad truth as climate change continues to make wildfires more unpredictable with larger variability, causing wetter years to build up fuels more rapidly and drier years to dry out the vegetation and extend the fire season, power outages due to high winds events are likely going to become much more common. While planned PSPS outages during high wind events are not a perfect solution, the cost of rebuilding from a wildfire will greatly exceed the relative minor damages caused by a multi-day power outage. Utilities have plans underway to modernize infrastructure and move to bury lines across the region where possible; however, this is not a silver bullet due the challenging topography in SoCal with numerous power lines running along mountaintops and ridgelines.

Why Not Residential Microgrids?

The concept of microgrids is not a new one and is often touted as a silver bullet to solve electrical grid issues. Microgrids are defined by a set of loads and energy storage devices that are grid-tied and can provide power when the larger grid as a whole is de-energized due to weather or maintenance. While microgrids seem to be implemented well for coordinated systems such as hospitals, schools and large commercial buildings that need 24/7 power and have strict backup power needs, the case for more dispersed residential microgrids is less clear. The main issues with a dispersed residential microgrid are how to handle coordination and energy scarcity in a power outage situation. First, most solar installations are “right-sized” to avoid excess costs from installing more solar generation capacity than a household will typically consume due to the poor net-energy metering payments from utilities now. Secondly, given some net metering scheme within the microgrid, energy scarcity during a grid shutdown would cause the marginal rate to shoot up to the point where most people would not consider using power at all; \$5/kWh does not really make sense when you can buy a $3 bags of ice to stick in your fridge to keep food from going bad. Lastly, the cost of installing solar and energy storage system benefitting a microgrid community would be expensive (depending on the region and sizing of the system, likely on the order of 5-15% of housing value on a per-house basis) and would be hard to manage and get buy in.

For emergency situations where power outages last 2-3+ days, sometimes the best solutions are the simplest - be nice and help your neighbors out in need, share your power when you have an excess, and work together a community to navigate these challenges.