I'm currently working on a reno project in my house and there is an attic fan that I hear running periodically. Does it save enough energy to be worth keeping(I'll probably need to buy a new one if I keep it)? I'd really just like to get rid of it. Thanks

Typically an attic fan is worth it. It's much better to have a 100 deg attic above you than a 150 deg above you, now the temperaure difference is only 20 to 30 degrees instead of 70 or 80. However, a new one might be a bit quieter.

If run properly, the attic fan can help in all seasons with regulating house temps. If you have one, definitely don't get rid of it and if the noise is getting on your nerves, then just replace it.

I see these things in stores all the time now. Are they easy to install or should I hire someone to help me put one of these things in?

Do these normally come in newer houses? I've never noticed them before.

I don't know if I have seen a new home in my area with an attic fan. It makes sense to put them it but I just can't see the bottom-line driven contractor spending the money to put these in and properly insulation attic spaces and/or install radiant barriers.

I personally try to design these into every house. Its a easy step that saves money. Most of the contractors I work with are familiar with the installation and operations which is important. If not properly installed or operated, you lose substantial benefit. Its just one step though. These aren't the silver bullet only one small measure each homeowner can take to save energy and money.