More RAM consumption usually means that you are either ...
- running more apps
- you are using apps that keep lots of things "cached" (i.e. gReader)
- you are running an app that uses a good chunk of the RAM (i.e. Skype)
More RAM usage doesn't necessarily mean more battery drain - it all boils down what the elevated RAM usage relates and what the apps using the RAM do. If it is "hogged" by lots of apps then you need to sort out what the apps are actually doing ... if they sync data or perform other tasks that keep you phone "busy" while sleeping you better expect a higher bat drain. Same goes for a large app (i.e. Skype) in case it keeps the WiFi going.
In short ... a higher RAM usage doesn't automatically leads to a faster battery drain, it only leads to it when the app(s) are keeping the CPU busy.