Smarthome gadgets are convenient, but what happens when the power goes out? Can you unlock an electric smart lock? Will all your smart lights come on at 3 a.m. when the power returns? And what about your garage door.

Power Outages Aren't Much Worse For Smart Homes

Power outages happen, and they're annoying to everyone. Every home depends on electricity to power climate control, lighting, internet, appliances, and so many other modern conveniences. A power outage is a problem in a smarthome, sure---but it's a problem in every home.

Let's be honest: Losing power in a smarthome isn't different from losing it in any other home these days. Most smart devices will stop functioning just like most "dumb" devices, but there are some things to keep in mind---especially for smart locks and some smart lights.

Smart Locks Are Battery Powered, and May Have A Backup

Just because you've lost power doesn't mean a smart lock has completely stopped working. Smart locks are battery powered, so the locking mechanism can keep working even when the rest of your home loses power. However, any remote capabilities that rely on the internet or a connected hub will not work. And that includes battery notifications, so if the power outage is expected to last you might want to replace your batteries as a precaution.

Batteries dying won't be a concern if your smart lock includes a keyhole. In that case, make sure to have your key, but if your smart lock features only a keypad or Bluetooth connection then go ahead and replace the batteries or at the very least test their charge. Some smart locks have terminals to receive a charge from a 9V battery as well; if that applies to you, then it may be worthwhile to store one in your car in the glovebox. For example, both the Schlage Z-Wave connect and the Kwikset Kevo have keyholes, while the Yale Assure Lock features a 9-volt battery backup option.

Smart Lights Might Wake You Up

While your power is out, your smart lights are the same as any other light---off. They won't do much of anything until you get power back, which is no surprise. The bigger question is what happens when the power comes back on. Many smart lights will stay off until you explicitly turn them back on. But some lights, like Philips Hue bulbs, can act differently. Depending on the current setting, these bulbs may turn on as soon as your power returns.

If your rooms, especially your bedrooms, are populated with Philips Hue bulbs, you might want to check the current setting and change it to “Power Loss Recovery,” which switches the bulb to the last-used state it was in before it lost power. That will prevent the bulbs from blinding you at 3 a.m. when your energy company fixes the power problem.

This is a setting you will want to think through; the default "power-on behavior" option is useful for quickly turning on your Philips Hue bulbs. If you have multiple light fixtures controlled by a single switch, the default behavior lets you turn the light switch off and on again to turn on all the connected smart bulbs quickly.

Without Power, Many Things Act the Same

Many of your other devices are no worse off than their dumb equivalent. Your smart thermostat has a battery backup, but that's mostly to keep working memory of your schedules. It can't do much without power to your HVAC system anyway, so if you don't have a backup for that, then the question of what the thermostat will do is moot.

The same goes for a smart garage door opener---most of these have a battery backup to lift and lower the door a few times. But if the battery runs out while you still have no power, the garage door opener will stop working (just like any other opener). You should be able to open it manually, though---hopefully, your torsion springs are in good condition.

If you aren't sure about the spring, take a look at the metal shaft that runs just above your closed garage door. You should see one or two tightly wound springs with a metal circle at the end. If the spring is separated into more than one part, it's broken, and you should get it replaced. Another quick test is to disconnect the garage door opening (there's usually a pull string) and try to lift the door yourself. If it's extremely heavy and won't stay up. you should call a repairman to look at your torsion springs.

Any smart cameras are unlikely to work correctly. If they do have a battery backup that may allow for local recording, but without internet, you'll lose any remote or viewing capabilities.  For example, Nest Cams need constant power and internet access, while a Sense8 camera has both local recording and a 2 hour battery backup. That won't get you through day-long power outages, but if power is only out for a short while it will help.

And without power, your voice assistants won't exist. You'll have to settle for talking to real people, break out the flashlights and tell ghost stories.

Most of these devices will be up and running shortly after you regain power, but some may need a reboot for good measure. Just check each smart device for working condition, especially if there's any fear of power surges trashing your electronics. For the most part, smart homes are no worse off than any other home that loses power. Just be aware of the few differences there are and prepare for them, and you should be fine.