It is perfectly safe, this does not affect the power being distributed around your house, also, it reduces the amount of cables you have in your house, so there is no need for drilling and it reduces mess!
> So if you are using mains power is PowerLine HomePlug safe?
> Why do I want a home network?
> Is PowerLine HomePlug Secure?
> Can I use PowerLine HomePlug with Apple MACs?
> Can I use PowerLine HomePlug with Linux Operating System?
> Do ZyXEL PowerLine HomePlug products conform to the Homeplug Alliance standards?
> What is the HomePlug Alliance and why was it formed?
> What is the difference between HomePlug 1.0 and HomePlug AV?
> Is HomePlug better than Draft N and 802.11n?
> Can I easily integrate PowerLine HomePlug into my Games Console?
> What to do when wireless can't deliver?
> Stream digital multimedia around your home
> Desktop or Integrated PowerLine Homeplug. Which version for you?
> Will PowerLine Products from two different manufacturers work together?