September 16, 2017

Survival Kit: Tesla Powerwall, solar panels, and electric vehicles brave the hurricane

If you’re in the path of a hurricane, is it better to have an EV, or a dinosaur-burner? Since Harvey and Irma’s unwanted visits, partisans on online forums have been fiercely debating this question.

Above: Having a Tesla in a hurricane can be a distinct advantage (Twitter: MKBHD)

Of course, each powertrain has its pros and cons. Obviously, the limited range of many EVs would be a problem if you have to “get out of Dodge” quickly (assuming you don’t choose to “hunker down”). To flee a hurricane in a Nissan LEAF or BMW i3, with a mere hundred miles of range, would be impractical, to say the least. However, the 200-mile-plus range of a Tesla should be plenty to get you out of the immediate disaster zone, or at least to the nearest Supercharger.

More than one Tesla owner glibly sailed past the lengthy lines that formed at gas stations all over the Southeast last weekend. Most of the Tesla Superchargers in Florida remained operational throughout the storm, with the exception of the one in the Keys, which went offline as the island chain took a direct hit from Irma.

Whenever disaster strikes, (most) companies do what they can to help, waiving fees and adding services to make it easier for people to evacuate. Tesla did its bit by remotely unlocking the full battery pack capacity of certain Model S and X vehicles. Some older Teslas have 75 kWh battery packs, but were sold as 60 kWh models - software limits the packs to the shorter range. Using its over-the-air update feature, Tesla was able to temporarily extend the range of these vehicles for Tesla owners in the danger zone. One Florida Model S 60 owner told Electrek that he was pleasantly surprised to find his range extended to almost 40 more miles than usual.

Above: Facing down a hurricane in the safest car on the planet (Instagram: pdespati)

Power outages are a regular feature of hurricanes - several days after the storm, thousands in Florida are still without electricity. This is a point against EVs, which could be out of action until the power comes back on. However, power outages can also strand ICE vehicles, as gas pumps require electricity to work. Gas stations in hurricane zones are generally required to have emergency generators, but there have been reports that some of these failed during the recent storm.

Whether you have an EV or an ICE vehicle, you’ll need a full battery or gas tank if you expect to get anywhere. The authorities tell us to keep our tanks full during hurricane season, and that’s good advice. In South Florida however, the lines started forming at gas stations days before the storm arrived, while EV owners simply went home and plugged in as usual.

All in all, it’s probably fair to say that a long-range EV such as a Tesla has a slight advantage over a legacy vehicle in the pre-storm evacuation phase. After the clouds clear however, that situation may be reversed if you live in an area where power is slow to be restored. In any case, tropical storms are not kind to automobiles - it’s estimated that over a million vehicles were destroyed in the flooding caused by Harvey.

Above: If power is out post-hurricane, you might need to locate a Tesla Supercharger (with power) in order to charge your Tesla (Instagram: pdespati)

While the advantages of EVs in a hurricane are debatable, the advantages of solar power combined with battery storage are clear. Orlando resident Andy Green told Fast Company that, thanks to his Tesla Powerwall, he was able to keep his lights on after a transformer failure plunged the rest of his street into darkness. “We didn’t have full power - we couldn’t have the whole house running - but we cut it down to the bare minimum, like air conditioning, refrigeration, internet, that sort of thing.”

Green’s power was off for 21 hours, as his Powerwall continued to deliver electricity. When the sun come out the next day, the battery started recharging.

Without battery storage, rooftop solar panels won’t do you any good in a disaster. Grid-connected systems are designed to automatically shut down if grid power is interrupted, because power fed back into the grid from solar panels could endanger utility personnel working on the lines upstream.

Above: Having solar panels post-hurricane paired with Tesla's Powerwall back-up battery storage can power your home (Image: Inhabitat via Paul Lukez Architecture)

However, a Tesla Powerwall provides not only load-shifting functionality (storing power generated during the day, and releasing it at night), but also a powerful emergency backup capability. Before the storm, Mr. Green set his system to fully charge. When the grid went down, the battery started delivering power to his 5,500-square-foot house. Given limited electric usage and enough sunshine to recharge the battery during the day, he believes he could have stayed comfortable for quite some time.

Looking at the bigger picture, rooftop solar combined with battery storage can make the power grid much more reliable and resistant to damage from natural disasters.

“A distributed energy resource - in other words, one that’s in multiple locations on the grid as opposed to just a centralized location - is obviously much more resilient because you don’t have a single point of failure,” says Christopher Burgess of the Rocky Mountain Institute, which is working to bring renewable energy to Caribbean islands that currently rely on expensive and dirty diesel generators. In Antigua, which escaped severe damage from Irma (unlike nearby Barbuda, which was devastated), the government has been installing microgrids, which incorporate solar panels and batteries, at hospitals and storm shelters.

Above: Tesla's Powerwall back-up battery storage shown with Tesla's high power wall connector (Image: Teslarati via Dennis Pascual)

As more households, businesses and community power projects install solar panels and battery storage, the power grid will become less vulnerable to storms and other disasters.

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