A more thorough explanation:

A standby charge is a fee that is charged for the availability of a service, regardless of whether or not the service is actually used. This fee is often based on the amount of land or property that is being serviced.

One common example of a standby charge is a fee that is charged by a utility company for the availability of electricity or gas. Even if a property owner does not use any electricity or gas during a given month, they will still be charged a fee for the availability of these services.

Another example of a standby charge is a fee that is charged by a fire department for the availability of emergency services. Property owners may be charged a fee based on the size of their property, even if they never actually need to use the services of the fire department.

These examples illustrate how a standby charge is a fee that is charged for the availability of a service, regardless of whether or not the service is actually used. This type of fee is often used to help cover the costs of maintaining and providing services, even if those services are not used by every customer.