On the Electric Load page in SAM, when you enter monthly data, SAM scales the data in the underlying hourly data set to match the monthly values you enter. The peak values result from the scaled data. You can see what SAM is doing by clicking the "View load data" button, and displaying both the "user-intered load power" and the "scaled load power" values in the graph. The "user-entered" data is the underlying hourly data, and the "scaled" data is that data adjusted to match the monthly bill totals you entered.
When you use a rate structure with tiered rates on the Electricity Rates page, SAM determines what rate ($/kWh) to apply to each block of kWh by month by looking at the tiered rate structure. For example, suppose the rate structure looks like this:
Tier 1: Max Usage = 100 kWh, Buy Rate = $0.05/kWh
Tier 2: Max Usage = 150 kWh, Buy Rate = $0.08/kWh
Tier 3: Max Usage = 1e+38 kWh, Buy Rate = $0.10/kWh
And, for January the total monthly consumption is 140 kWh. The resulting energy charge for January would be:
100 kWh * $0.05/kWh + 40 kWh * $0.08/kWh kWh = $8.2
Note that Tier 3 is never reached in January because the total consumption is below 150 kWh.
Best regards,
Paul.
