UK homes are consuming much more electricity than previously thought, a report says.
The Energy Saving Trust (EST) discovered devices left on standby, or just left switched on, can make energy bills nearly one fifth higher.
That's double what they thought and Paula Owen, the report's main writer, said: "It was quite a shock."
Big energy eaters include fridges, freezers, microwaves, computers, and even mobiles on charge.
How do you save energy at home?
Attempts have been made to make products to help. The BBC show Dragons Den featured the Standby Saver - over a million were sold.
Switching off standby can save as much as £80 a year - that could pay for a new smartphone!
The EST wants people to buy devices which save energy, but they can be expensive. And some TVs left on standby are thought to last for longer. So it's confusing to know what's best!
We wanted to know what YOU do to save energy in your home. Thanks for all your comments. Here's what some of you said:
"My family saves energy by putting my TV on a timer."
Bradley, Wrexham, Wales
"Instead of getting home from school and watching TV or going on the computer, play with your friends at the local park or make something interesting to amuse yourself."
Jessica, Northumberland, England
"My mom, dad and cousin Forest used to forget to turn things off so now we put notes on the wall saying if we are watching TV. At the end of the day we will look at the notes and turn everything off."
Elizabeth, CA, USA
"My family use a washing line to dry clothes instead of a tumble drier and also keep everything switched off when it is not being used."
"Me and my family save electricity by saving light and I also try to not watch too much television and try not to switch too many or more than 2 lights on at once."
Tanha, London, England
"Instead of watching TV and going on the computer I go to the park, read, play with my sister and use my imagination which I think is fun, rather than using electrical devices!!!"
Izzy, Surrey, England
"I think we should all turn electricity off properly, my family does because it's not safe to leave things on stand-by."
Malaika, Essex, England
"I save energy by switching everything off before bedtime."
Lucas, Leicester, England
"The way I save electricity is by instead of watching TV, I read for two hours."
Kaleb, Merseyside, England
"At home, my family and I save electricity by not using too many lights and remembering to turn them off. Not only does it save energy, it saves money too."
Maika, Bognor Regis, England