Google Assistant has been able to turn lights on and off for a while, but until now, it could only do so immediately. This meant that it didn't have the capability to run a timer and perform the action after the time had elapsed. Thankfully, the digital helper has gotten even smarter and can now operate your lights according to the time or duration you specify.
You can now tell Google Assistant to "turn the lights off in five minutes," or even to switch them on at a specific time, such as "turn on the living room light at 5:45 PM." Similarly, you can ask it to switch a light on for a specific amount of time by saying, "turn on the entrance light for five minutes." I've even been able to schedule events for the following day but haven't succeeded in scheduling them several days in advance.
While the above features can come in handy, they still need a bit of work. First, when asking Google Assistant to do something "tomorrow," you need to specify the exact time, or it'll just acknowledge your command without asking for clarifications. Also, if for whatever reason it misunderstands you and decides to turn your home into a disco in the middle of the night, there doesn't seem to be a way to cancel the request — although you can always ask it to turn the lights off a minute later. Thankfully, Google's official documentation indicates Assistant should be able to cancel a scheduled action, so this should be fixed soon.
I've also been able to ask Google to turn my lights on or off at sunset or sunrise, with it confirming the exact time at which it will perform the action. That's pretty useful if you're working from home and want your lights to be automatically turned on when it gets dark