Because the grid is unlike any other Component, HOMER calculates the costs associated with the grid in a unique way. The grid cost output calculations are described below.
If the system is connected to the grid and contains some other power producing device (such as a microturbine, fuel cell, PV array, or wind turbine), the grid capital cost is equal to the interconnection charge. Otherwise, the grid capital cost is zero.
The replacement cost of the grid is always zero.
The grid O&M cost is equal to the annual cost of buying electricity from the grid (energy cost plus demand cost) minus any income from the sale of electricity to the grid. For grid-connected systems that contain some other power producing device (such as a microturbine, fuel cell, PV array, or wind turbine), the grid O&M cost also includes the grid standby charge.
The fuel cost of the grid is always zero.
See also