If I wish to monitor the consumption values of some household appliances do I always need the load control module 01455?

No. If you only need to measure the consumption of one or more loads, all that is required are articles which support the "current sensor" function, such as 01450, 01456, 01451 and flush mounting actuators 14537. To view and save the data, you will need a touchscreen and/or webserver type supervision device