Note: Are you going to be modelling fees for this incentive? You should check out our article on Modelling SREC Variable and Holdback Fees first as they may impact the values that you set up here.
The modelling of SRECs for the Illinois Adjustable Block Program for Small System Sizes (<=10kW) is written up in an article here. However, the modelling of larger systems sizes (>10kW) is more complicated and therefore requires some more set up which is outlined in this article.
There are two options that are available to model this in OpenSolar.
This option is more simple to set up and it will model the solution except for the modelling of the timing of the quarterly payments. This will not greatly impact the net cost and financials (1.5% error for 10kW and 0.04% error for 200kW on the total net cost to the customer), however it does impact the repayments graph.
However, you are able to explain this to the customer This can be explained in the disclaimers (Control>Proposal Templates>Edit>Proposal Content>Disclaimers) or contract in the installers account.
In order to set this up:
- Set up one incentive (for each of the system size ranges) for 20% of the total incentive which will be paid to the customer (home owner).
- Go to Control>Incentives>Create and enter the fields shown below
- Calculate the $/unit as: $/kW AC = AC/DC ratio * 20% * ( Current Block Price of REC * 16.42% * 8760 [hr/year] * 15 [years] ) / 1000. So for the case of 10-25kW (assuming block 1 and an AC/DC ratio of 0.88) it would be: 0.88*0.2*(78.7*0.1642*8760*15)/1000 = 298.32. Note: this amount should be less if there is a 5% holdback fee.
- Convert the
- Ensure the incentive is to the customer
- Save
- Repeat for all other system size ranges updating the relevant fields (such as title, $/unit, min max limits)
- Set up another incentive (for each of the system size ranges) for the remaining 80% which will be to the customer and therefore reduce the net cost of the system overall.
- Go to Control>Incentives>Create and enter the fields shown below
- Calculate the $/unit as: $/kW AC = AC/DC ratio * 80% * ( Current Block Price of REC * 16.42% * 8760 [hr/year] * 15 [years] ) / 1000. So for the case of 10-25kW (assuming block 1 and an AC/DC ratio of 0.88) it would be: 0.88*0.8*(78.7*0.1642*8760*15)/1000 = 1195.39. Note, this amount should be less if there is a 5% holdback fee. Simply multiply by 0.95 if the holdback fee is 5%.
- Ensure the incentive is to the customer
- Save
- Repeat for all other system size ranges updating the relevant fields (such as title, $/unit, min max limits)
Note: These will automatically apply in studio when you design systems.
You will also need to set up a disclaimer to explain to the customer that 80% of the incentive is repaid quarterly from the start of year 2 to the end of year 5.
This is how it will appear in the proposal:
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This is a more complicated set-up but will properly model the repayments fully.
- In the same way as option 1, the initial 20% incentive should be set up for each of the system size ranges. This will be applied automatically
- Set up the repayments for each of the system size ranges
- Go to Control>Other Components>Create>Enable additional costs and fill it out as follows:
- Calculate the $/kW as follows: $/kW AC = AC/DC ratio * 80% * ( Current Block Price of REC * 16.42% * 8760 [hr/year] * 15 [years] ) / 1000 / 16 [quarters], so for 10-25kW (assuming an AC/DC ratio of 0.88) it would be: $/kW = 0.88*80% * ( 78.7 * 16.42% * 8760 [hr/year] * 15 [years] ) / 1000 / 16 [quarters] = 74.7 Note, this amount should be less if there is a 5% holdback fee. Simply multiply by 0.95 if the holdback fee is 5%.
- Save
- Repeat for all other system size ranges
This is how it will look in MyEnergy:
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To apply in studio, go to Other Components on the left hand side bar and add in the relevant component to model the payments. You will need to do this manually for each design.
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