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HOMER Pro 3.9

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Total Net Present Cost

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The total net present cost (NPC) of a system is the present value of all the costs the system incurs over its lifetime, minus the present value of all the revenue it earns over its lifetime. Costs include capital costs, replacement costs, O&M costs, fuel costs, emissions penalties, and the costs of buying power from the grid. Revenues include salvage value and grid sales revenue.


Output Variable





HOMER calculates the total NPC by summing up the total discounted cash flows in each year of the project lifetime.

The total NPC is HOMER's main economic output, the value by which it ranks all system configurations in the optimization results, and the basis from which it calculates the total annualized cost and the levelized cost of energy.

See also

Net Present Cost

Total Annualized Cost

Levelized Cost of Energy