Toward An Understanding Of How Net Metering Works On A Hourly Basis
To expand this example of net metering, you should note a few things from this hour by hour breakdown of consumption and production on a day when a credit of 4 kWh was generated.
Between midnight and 7AM the solar modules were not producing. You'll see that on a hourly basis this house used around 500 Watts or 0.5 kWh/hour for background functions like running refrigrators, water purifiers, standby loads for television/computers etc. We'll call this the baseline. With no additional loads like dishwashers, dryers, electronics on, this house will use at least 12 kWh/day (.5x24).
The solar array kicked in around 8AM and by 9AM it began to generate credit. In other words, it produced more than the house needed. That band of credit between 9AM and 5PM was enough to create an overall credit for the day.
A key goal with net metering is to create enough rolling credit in Spring, Summer, and Fall to offset power consumption and lower production during the Winter. This is why we don't need batteries on grid-tie arrays like this.