Minimising power consumption

I have an 8MHz Pro Mini 328p used as a wireless temp sensor. I've removed the 3.3V regulator and the power LED, I'm using RocketScream's low power library and it's still using 2mA when sleeping.

Is there a way I can reduce this further on these boards or should I go bare bones and use a 328p DIP chip instead?

Check Nick Gammon's site on power - http://www.gammon.com.au/forum/?id=11497 -

28uA. That's what I'm down to now with a barebones running off the internal clock. Roughly 100 times less than the 2mA.

Is it possible to get the same sort of power consumption with the Pro Mini boards or are there too many components on them to go that low?

Ok, not quite 100 times. Only 71x. But still much better.

I've done some testing tonight. Had a current of 22uA flowing through the circuit running off the batteries. Adding the 3.3V step up increased that to 81uA, about a 4x increase. So I'm thinking battery power is the way to go.

I think I've finally done it. I've got a temperature sender that is using about 4uA when sleeping.

Waking up once every minute that should last quite a while.