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LEAC and Energy Rates on Guam
- frohro
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27 Jan 2020 00:27 #7900
by frohro
Replied by frohro on topic LEAC and Energy Rates on Guam
Hi Paul,
I used the SAM gui to simulate a PVwatts system on Guam, without letting the LEAC change as a function of time to make sure it was worth simulating what happens with a changing LEAC. I was using the beta version of SAM. Now I'm wondering if I should have used the release version of SAM to do that. I want to generate a .json file and import it in PySAM. Are they compatible?
Thanks,
Rob
P.S. It would be really nice if there were some examples using pvsamv1, utilityrate5 and cashload. Can you point me to any?
I used the SAM gui to simulate a PVwatts system on Guam, without letting the LEAC change as a function of time to make sure it was worth simulating what happens with a changing LEAC. I was using the beta version of SAM. Now I'm wondering if I should have used the release version of SAM to do that. I want to generate a .json file and import it in PySAM. Are they compatible?
Thanks,
Rob
P.S. It would be really nice if there were some examples using pvsamv1, utilityrate5 and cashload. Can you point me to any?
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- frohro
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27 Jan 2020 00:35 #7901
by frohro
Replied by frohro on topic LEAC and Energy Rates on Guam
Hi Paul,
I think I found my answer. PySAM.Pvwattsv7 does not exist, but PySAM.Pvwattsv5 does.
I'd still like some examples.
Thanks,
Rob
I think I found my answer. PySAM.Pvwattsv7 does not exist, but PySAM.Pvwattsv5 does.
I'd still like some examples.
Thanks,
Rob
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- pgilman
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27 Jan 2020 10:32 #7902
by pgilman
Replied by pgilman on topic LEAC and Energy Rates on Guam
Hi Rob,
The JSON inputs file you generate with different versions of SAM are not necessarily compatible because different versions of SAM run different versions of SSC, and SSC inputs may change between versions.
As you discovered, the Beta version of SAM 2020 uses pvwattsv7 instead of pvwattsv5, and pvwattsv7 does not exist in older versions. The SAM release notes list differences between versions, and also identify the SSC version number associated with each version of SAM:
nrel.github.io/SAM/doc/releasenotes.html
As for examples, I will look into getting some posted.
Thanks,
Paul.
The JSON inputs file you generate with different versions of SAM are not necessarily compatible because different versions of SAM run different versions of SSC, and SSC inputs may change between versions.
As you discovered, the Beta version of SAM 2020 uses pvwattsv7 instead of pvwattsv5, and pvwattsv7 does not exist in older versions. The SAM release notes list differences between versions, and also identify the SSC version number associated with each version of SAM:
nrel.github.io/SAM/doc/releasenotes.html
As for examples, I will look into getting some posted.
Thanks,
Paul.
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- frohro
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27 Jan 2020 17:50 #7904
by frohro
Replied by frohro on topic LEAC and Energy Rates on Guam
Hi Paul,
I'm running into another problem. The beta version has Grid Limits, which I need, as GPA allows us only 100 kW, but the 2018 version does not have Grid Limits. It looks like this means that I need a PySam wrapper for an updated version of utilityrate5 or cashmodel. Is the PySAM wrapper updated with grid limits?
I'm able to get some ball park estimates with the 2020 beta version of SAM ignoring LEAC changes, but the issue here is that in 2022 GPA is putting in 200MW of solar generation, and this is going to approximately reduce the LEAC charges from $0.15/kWh to $0.10 or so. I really need to see what happens with the step going down to $0.08/kWh. In addition to this, GPA is doing everything they can to change the net metering to just reimbursing avoided cost, which I was hoping to model with variable charges. I'm just wondering if I should rethink my plan. What is the best way to deal with these variable rates? I'm open to any ideas.
Thanks,
Rob
I'm running into another problem. The beta version has Grid Limits, which I need, as GPA allows us only 100 kW, but the 2018 version does not have Grid Limits. It looks like this means that I need a PySam wrapper for an updated version of utilityrate5 or cashmodel. Is the PySAM wrapper updated with grid limits?
I'm able to get some ball park estimates with the 2020 beta version of SAM ignoring LEAC changes, but the issue here is that in 2022 GPA is putting in 200MW of solar generation, and this is going to approximately reduce the LEAC charges from $0.15/kWh to $0.10 or so. I really need to see what happens with the step going down to $0.08/kWh. In addition to this, GPA is doing everything they can to change the net metering to just reimbursing avoided cost, which I was hoping to model with variable charges. I'm just wondering if I should rethink my plan. What is the best way to deal with these variable rates? I'm open to any ideas.
Thanks,
Rob
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- frohro
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27 Jan 2020 23:54 #7906
by frohro
Replied by frohro on topic LEAC and Energy Rates on Guam
Hi Paul,
I found that it would be handy to be able to use the sdktool. I'm using linux and when I search my filesystem for sdktool, I find it in the source code (which I still haven't successfully built), but not in the binary installations? Where do I get a binary version?
Thanks,
Rob
I found that it would be handy to be able to use the sdktool. I'm using linux and when I search my filesystem for sdktool, I find it in the source code (which I still haven't successfully built), but not in the binary installations? Where do I get a binary version?
Thanks,
Rob
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- pgilman
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28 Jan 2020 17:10 #7909
by pgilman
Replied by pgilman on topic LEAC and Energy Rates on Guam
HI Rob,
We just released PySAM 2.0.2, which is based on SSC 233 and should include the grid limit and other new features currently available in the Beta version:
nrel-pysam.readthedocs.io/en/master/Version.html
See the SAM release notes for information about the different SAM and SSC versions:
nrel.github.io/SAM/doc/releasenotes.html
One option for dealing with changing rate structures might be to run a separate simulation for each year of the cash flow to calculate an array of annual bill savings over the financial analysis period, and then use that array as input to the cashloan module. That would make it possible to change the electricity rate inputs on a year-by-year basis.
Best regards,
Paul.
We just released PySAM 2.0.2, which is based on SSC 233 and should include the grid limit and other new features currently available in the Beta version:
nrel-pysam.readthedocs.io/en/master/Version.html
See the SAM release notes for information about the different SAM and SSC versions:
nrel.github.io/SAM/doc/releasenotes.html
One option for dealing with changing rate structures might be to run a separate simulation for each year of the cash flow to calculate an array of annual bill savings over the financial analysis period, and then use that array as input to the cashloan module. That would make it possible to change the electricity rate inputs on a year-by-year basis.
Best regards,
Paul.
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