Economic evaluation: Units and batch mode

[jammyc]

Hi,

Two part question:

1) How does PVsyst update costs if the project parameters (e.g. qty or size of modules) subsequently changes? Does PVsyst "remember" whether a cost was input as XX absolute, XX/Wp or XX/m²? What about if I define a custom cost item?

2) Is this also applied due to changes in batch mode, or are they lumped somewhere?

Spurious example, it is convenient to input the grid connection costs as a fixed XX, inverter price as X/unit, but module price as X/Wp. If I then change both the qty inverters and qty modules in batch mode, will the costs change as I expect?

I have historically carried out the economic evaluation as a post-simulation process, so apologies if this is obvious and I've missed it.

Thanks in advance

[Hizir Apaydin]

Hi,

Two part question:

1) How does PVsyst update costs if the project parameters (e.g. qty or size of modules) subsequently changes? Does PVsyst "remember" whether a cost was input as XX absolute, XX/Wp or XX/m²? What about if I define a custom cost item?

2) Is this also applied due to changes in batch mode, or are they lumped somewhere?

Spurious example, it is convenient to input the grid connection costs as a fixed XX, inverter price as X/unit, but module price as X/Wp. If I then change both the qty inverters and qty modules in batch mode, will the costs change as I expect?

I have historically carried out the economic evaluation as a post-simulation process, so apologies if this is obvious and I've missed it.

Thanks in advance

 

Dear jammyc,

The price type selection (global, by wc, by m2) is applied for all the costs you defined.

Let's say you define a fixed grid connection cost of 10000$. Then you want to define module price per Wp.

So you change from "Global" to "by Wp". This will automatically transform the grid installation cost price from 10000$ to a price per Wp (for example 1$ if you have an installation of 10000wp). All other costs you defined are also updated to a "by Wp" cost.

However, when you change your quantity parameters in PVsyst system Window, only system dependent costs are automatically updated in the economic evaluation (module, inverters and battery costs according to quantity).

None of the other costs are changed, even if you defined them per wp or per square meter. If you defined a custom cost item, its amount is not changed when resizing your system.

The new cost calculation for system dependent cost is done by quantity. Let's say you have defined a module cost of 1$/wp in the ecomomic evaluation. If you change your module quantity in the system, the price calculation is done according to quantity ("Global option"), even if you selected "by Wp" to initially define it. But the cost will still appears as "by wp" in the ecomomic evaluation window, but its value should have been modified.

Regarding the batch mode, the economic evaluation parameters are not modified. However you can select economic evaluation parameters as output parameters of the batch.

The updated costs will then appear in the results column of your resulting excel file. You have to check the "Number of modules" or "Number of inverters" parameters in batch simulation input parameters if you want to see the economic impact of changing these quantities in the batch output results.

Kind regards

[jammyc]

Hi Hizir,

Thanks for the response.

For various reasons I've only just had chance to have a quick play with a test project, but if I understand correctly, in batch mode:

Installation costs:

• Anything listed under "PV modules" is scaled by the qty of modules, regardless of module STC rating
• Anything listed under "Inverters" is scaled by the qty of inverters, regardless of inverter rating (etc)
• Everything else (other components, studies etc) is fixed and does not change for the entire batch

Operating costs:

• All OPEX is fixed

It looks like the quantity for inverters and module sub-costs is automatically adjusted to be equal to the inverter and module count even for the rows that are not greyed out?

[Hizir Apaydin]

On 3/16/2022 at 7:07 PM, jammyc said:

Hi Hizir,

Thanks for the response.

For various reasons I've only just had chance to have a quick play with a test project, but if I understand correctly, in batch mode:

Installation costs:

• Anything listed under "PV modules" is scaled by the qty of modules, regardless of module STC rating
• Anything listed under "Inverters" is scaled by the qty of inverters, regardless of inverter rating (etc)
• Everything else (other components, studies etc) is fixed and does not change for the entire batch

Operating costs:

• All OPEX is fixed

It looks like the quantity for inverters and module sub-costs is automatically adjusted to be equal to the inverter and module count even for the rows that are not greyed out?

Dear jammyc,

Yes that is correct. All costs related to modules and inverters are automatically updated from the system. The other installation costs and the operating costs remain fixed as the price variation may not be proportional to the module or inverter quantities (for example, multiplying the number of modules by 2 does not necessarily multiply the "environmental studies" or the "insurance" costs by 2). For a financial performance comparison between different sizes of system, manually performing the economic analysis and reviewing all individual costs for each system would be more precise than using the batch mode comparison.

Regards,