Hi Brett,
The "value of electricity savings" in the cash flow is equivalent to the annual electricity bill savings, which SAM calculates by subtracting the "bill without system" from the "bill with system." In other words, SAM determines what the annual electricity bill would have been with no renewable energy system ("without system") and what it is with the system ("with system"), and considers the difference between the two to be the value of electricity savings.
The electricity bill with system depends on the amount of electricity generated by the system, the electricity consumed by the building, and the rate structure used to calculate the electricity bill. You can see how SAM accumulates kWh into the different time-of-use periods and tiers, and how it assigns a dollar amount to each on the Data Tab of the Results page by expanding the "Electricity Rate Data by Tier and Period" section of the variable list.
When you specify energy charge rates with tiers, you need at least 2 tiers, one to specify the rate for the first block of kWh, and one for the rate for any kWh in excess of the first block. So, your Scenario 1 should look something like this:
And, for Scenario 2, there should be two tiers for each of the 6 time-of-use periods.
Finally, the option you choose for how SAM handles excess generation will affect the electricity bill calculation. For a rate structure with both time-of-use periods and tiers, the excess generation may accumulate by period and tier within each month, and may roll over into next month's periods and tiers in different ways depending on the option.
I hope that information is helpful as you explore your results. If you would like more specific feedback on your analysis, please attach your .sam file to your original post above by editing it and using the links to add an attachment.
Best regards,
Paul.