By default, the OnGrid Tool increases the total system cost, when, for example, a system is installed on Spanish Tile, installed on a steep roof, and/or has a wire run length of at least 50 feet.
These are known as "adders." The effect of the adders on system cost is detailed in rows 514 to 519 in the Inputs sheet.
To permanently remove adders and prevent them from affect system cost, go the Pricing sheet, cell G110, and click on "Clear Adder Amounts." You should see the yellow column in the Adders section become blank.
Alternatively, you can set the adder amounts per your specifications. At this time, they can only be set in terms of dollar per watt in the Pricing sheet, Adders section, or total amount in the Inputs sheet, System Pricing & Results section.