Perhaps, similar to sails, they make a useful backup for when the lights go out.

也许，和风帆一样，它们作为备用品可以在熄灯的时候排上用场。

youdao

And, perhaps, similar to sails, they make a useful backup for when the lights go out.

也许，和帆船一样，它们在熄灯的时候可以作为有用的备用品。

youdao

However, solar lights are very useful if you are simply looking for a bit of ambience.

不过，太阳能灯，是非常有益的，如果你只是在寻求一个位元的氛围。

youdao

"We see these developments as tremendously useful in defeating the remaining lights class actions scattered around the country, " Campagnino said in a research report of the expected difficulties plaintiff lawyers may have in cherry picking litigation-friendly states for lawsuits.

FORBES: Magazine Article

In China, Christmas light recycling plants will process some 20 million pounds of Christmas lights and recycle them into useful products.

ENGADGET: Inhabitat's Week in Green: biological concrete, flexible solar cells and the top wearable tech of 2012

Take a look at the Spark Device project on Kickstarter (link at top of post) and imagine how useful it would be to control your lights with a simple device and app.

FORBES: Reinvent The Light Bulb With Spark Devices