NREL is developing a work plan for a project to improve SAM's financial modeling capabilities. This work could include modifying existing models, adding new ones, or both. For a description of SAM's current financial models, see:
We are already working on
improvements to SAM's electricity bill calculator
for behind-the-meter projects, and we do have some ideas for
financial model fixes and enhancements
, but would love to hear your suggestions. Is there a financial structure you would like to model in SAM that is not available in the latest version? Are there financial model inputs or results you would like us to add? Please let us know by posting a response to this post.
Paul and the SAM team.
Thanks for creating this forum. It's very timely. Yes, I'd like to see a third party ownership model (host/developer) that includes an Energy-as-a-Service (EaaS) and Microgrid-as-a-Service (MaaS) financial model. I'd like to be able to choose what % of the total savings from the CAPEX investment to share with the host including a buy-down option for them, and then show the returns for both the host and the developer. You can run this type of analysis right now, but it takes modifying the exported spreadsheet. It'd be nice to run it within the SAM environment.
And finally, it would also be great if we could run a solar+BESS+fuel cell resiliency/savings analysis of the same type within the SAM environment. Thanks, Brian
1) It would be good to have the PPA solver to solve for a multiple of the vector PPA input (provided by user in SAM) to reach an IRR target. - Currently SAM solves for a single PPA rate
2) A schedule of customer buyout values (in $) for PPA's based on owner holding period return (input as a period 0 to buyout year IRR for each time period). At a minimum good to have these for buyout in years 6,10, 15, 20, 25 and term of PPA.
As an example:
This provides offtaker of PPA's a quick way to evaluate PPA offers including buyout values provided on the standard SEIA PPA form.
3) Solver to solve "Total Losses" in System Design in PVWatts to solve for a user input Energy Yield (kWh/kW) (override PVWatts estimate)
One of the main limitations in using SAM to model power plants in another country is that we use a Value Added Tax scheme instead of a Sales Tax. This tax applies to the investment costs as well as to the revenues, while the sales tax only applies to the investment cost.
I have no problem applying the VAT to the Investments part, since I can input it as a sales tax. On the other hand, I'm having problems applying it to the Total Revenue part. I have already searched for a solution but found none which would solve the issue correctly. If there is already an available way to work around this issue I would thank you if you could let me know.
Having said this, my suggestion/request would be to implement a way to decide whether to use Sales Tax or Value Added Tax, since this would improve the model applicability in many other countries.
Here is a suggested workaround to model the 16% VAT in Mexico:
Add a sales tax of 16% to match the 16% Value Added Tax. This inserts the VAT to the cash flow.
Set the total depreciation basis to 86.2% to remove the VAT from the depreciation basis, since the VAT does not depreciate in the long term, as required by law. (Will probably differ from country to country)
Add a IBI of 16%. Since the 16% VAT tax you paid is going to be in your favor when total taxes are calculated. (Will also probably differ from country to country)
Add a State tax of 13.8%. Since the cash flows now have the VAT added to them, this will correspond to the VAT that will need to be paid.