Carbon neutral is not zero carbon as many will think. It actually means how you can reduce carbon emissions to zero. Broadly speaking, achieving carbon neutrality can be done by carbon offset or carbon reduction. These steps involves several factors to be conducted at an organisational level. I will briefly mention how this can be done for an product owner.

Carbon Offset with Integration
The way to offset your carbon usage in your application is to understand the usage patterns and consumptions. This means you will require a carbon footprint summary of the application inputs and outputs. Carbon offset can usually be achieved via direct integration to other applications. Integration reduces carbon usage by replacing paper transfer or email exchanges of processes between applications.
Carbon Reduction with Auto Scaling
Auto scaling is the most popular for carbon reduction in an application. Idling time are a wastage of carbon if servers are running at full capacity. Vice versa, under capacity creates backlogs and delays. This results in process congestion and exceptions handling. Auto scaling helps in right sizing capacity for efficiency and reduction of carbon usage.
Carbon neutrality can be done for product owner using two basic changes. You can offset your carbon by direct integration with your partners. At the same time, you should also enable auto scaling to maximise your server capacity and usage for different consumption period. Thus, your carbon reduction will be at an optimal level.