Powerwalls and Power Outages

Look at the map above. This is the region where I live. More than 55 thousand people here are currently without power right now. We had an Arctic blast blow through with snow and ice last week and this week there's a wind storm taking out branches and trees. To pile on to all of that, there's domestic terrorist movement that somehow thinks that attacking electrical substations will manifest their extremist political agenda.

Tesla Powerwalls don't have a "grid under attack" setting (yet). 

There's no good time to lose power, but during a winter storm is the worst. Without power, you cannot run your furnace to stay warm. This is true even if you have a gas furnace because power is needed to run the fans and control systems. If you opt to evacuate to stay with friends or family or to check into a hotel, the road conditions can make travel difficult. These storms and outages can be deadly.

Powerwall to the rescue

So here we are with our Powerwall full and the lights flickering occasionally. We are getting a meager amount of solar production on this rainy winter's day. Even with a small amount of solar production, this can stretch the battery uptime significantly. 

Here's something that many people without solar on their roof don't know. If you have solar without batteries (the most common type of solar installation), when the grid goes down, your solar turns off. This seems like the time when you'd need it most, but there are a couple of reasons it works this way. It's unlikely that your solar will create exactly the amount of power that your home needs. If it doesn't make enough, you'll brownout your home and could damage your more sensitive equipment (computers, TVs...). If your solar makes more than your home currently needs, it has to go somewhere. This would usually be the grid, but if the grid is down, it can't go that way.

This is where Powerwall comes in handy. Even when the grid is down, it can fill in the passing cloud  gaps and prevent the brownout that might fry your flat screen and it can absorb the surplus for use after the sun goes down.

A distributed power grid is more resilient and a harder target for weather or violent extremists to attack.