Given that we are seeing more and more PV+BESS systems with incentives, there is a need to be able to have an IBI that is vector based.
For example for modeling SGIP incentives in California, the total SGIP rebate is split into 50% upfront which can be modeled as an IBI.
The remaining 50% is split into 5 annual installments of equal dollar value.
Will be nice to direclty model that. Today we run SAM once, get annual kwh for each year and then convert the IBI into PBI and re-run SAM.
I've automated that completely with LK but having a direct input will make it simple.
I really like this modeling service.
Although I would like to have more freedom on all the units in the model.
Mainly regarding the System Costs. Indeed; when I use SAM for projects over 5 MW the units such as $/W are inconvenient. Firstly because SAM only allows 2 decimal places, and when putting more it automatically rounds up to 100th of the value.
Second, all of my data are in €/kW. The currency is not an issue, but always having to divide by 1000 can sometimes lead to stupid mistakes, and hinders the ability of giving multiple decimal places digits.
The same goes for the area in Land cost. Having the option to use Hectares instead of acres would be nice, especially when m² are already used in the software.
What about land lease? You can only use land lease in some categories, but not in all of them. Moreover, what about land securing cost? I won't start paying my full lease until the project is built, but I still need to pay a portion of it to keep the privilege of security.
Lastly, regarding Loans. I would like to be able to make different loans at different times with different interest rates.
Thanks a lot for what has been done already,
We can change the formatting of numbers on the System Costs page to display more decimal places and avoid rounding numbers. Part of our thinking was to communicate that the model makes cost estimates rather than precise predictions, but I can see where that behavior might not be desirable.
As for the $/W units for the PV models, that convention is based on the history of U.S. Department of Energy using $/Wdc in photovoltaic cost studies, such as
these NREL benchmark costs
. However, other NREL cost reports such as the
Annual Technology Baseline
use $/kW. We'd be hesitant to change the units in SAM to $/kW for those people who are used to working with $/W
The land costs are designed for projects that purchase land. I agree that solar projects often lease land. You can account for that cost as an operating cost, but we will consider adding a specific category for land lease. You could use the "land purchase" category to represent the cost of securing the land lease, and then use the fixed annual O&M cost to represent the annual lease payment.
I'm not sure we will add more complexity to SAM's loan model. We try to strike a balance: It should model enough features to be useful to a wide range of users, but not so many as to be confusing.
One way to add complexity to the financial model for your own purposes is to set things up initially in SAM, and then use the "Send to Excel with Equations" option (Windows only) to export data from SAM to a fully functional Excel workbook that replicates SAM's financial model. You can then make changes in Excel to model the details of your project.