Why it is worth looking at your consumption
Without data, any sizing is guesswork. Once you know how much you use and when, you can decide better whether you need panels, a battery or simply a change in a few habits.
Level 1: the bills
Start with the bills for the last 12 months: monthly consumption in kWh shows the difference between the seasons. What they do not show is when during the day you use the energy.
Level 2: data from the meter or the supplier
Some meters and some suppliers offer a more detailed history, sometimes in hourly intervals. Check what is available in your account.
Level 3: an app, a smart meter or current clamps
A dedicated solution measures the house’s consumption at the consumer unit and sends it to an app. If you have a photovoltaic system, the inverter app can also show output, and with a meter or clamps you get both consumption and the exchange with the grid as well. See energy monitoring from your phone.
What to do with the data
- spot the large loads and the hours when they run;
- move some consumption into the sunny hours, if you have panels;
- compare the months and notice anything unusual;
- use the data for more realistic sizing, through energy consulting.
Bear privacy in mind: consumption data describes the habits of the household, and apps usually send data to the manufacturer’s servers. Check the privacy policies and secure your account.