Hi,
It's my first post but I have been watching the progress of Lars project.
So let's go:
I have a similar situation with the beehives.
I want to monitor the weight of a freezer full of product to see if it is getting empty (when it becomes light), to send more products without the need to send someone to check.
This could also serve to warn about an interruption in the supply of freezer energy, so I could check what happened before the melting of the products. 
I was thinking of installing the weight ranges between the wheels and the base of the freezer and a system that would send daily (or on demand) weight measurements by sms.
Energy would be no problem because the system could be connected to power supply of freezer.
Is there any practical and feasible way to test this idea?
I appreciate any consideration. 