Danish company Modstroem uses non-standard approach to get information about energy consumption in the its Z-Wave-based monitoring system. Instead of sensor the system includes digital camera which transmits picture from the meter to the Z-Wave Internet gateway. That gateway allows no only see the results of measurements but control all Z-Wave stuff in the home remotely.
Not sure that it’s good idea to use camera to grab data from the meter. In my opinion using the sensor makes measurement more accurate and independent from external actions such lighting, dust etc. It seems for me like a field-work but not effective solution for practice using.