Battery system + PV calculation questions

[AG_0113]

Hi,

I have severall questions in connection with your calculations for PV systems + battery storage systems for own consumption + sell to the grid:

1. How IRR of Capital Resources is calculated (please specify formula which PVSol is using)?
2. How Electricity Production Costs are calculated (please specify formula which PVSol is using)?
3. Battery Charge (Grid) (in Simulation Results, Battery System section) – Can you set up PVSol in such a way that it charges battery over the specific time (eg. in the night)? If yes -> how? If not -> what this parameter shows?
4. Service Life (Simulation Results, Battery System section) – what does it mean?
5. Minimum System Operating Period (in Financial Analysis, Overview section) -> please explain what does it mean?
6. Questions regarding Remuneration and Savings section in Financial Analysis, Overview chapter:
   1. Total Payment from Utility in First Year – please explain what does it mean and how is calculated
   2. First year savings – please explain what does it mean and how is calculated
   3. Own Use Remuneration – please explain what does it mean and how is calculated
7. Questions regarding Cash Flow section:
   1. Feed-in / Export Tariff– please explain what does it mean and how is calculated. Why this figure is different than “Total Payment from Utility in First Year” figure showed in Remuneration and Savings section in Financial Analysis, Overview chapter?
   2. Electricity savings – please explain what does it mean and how is calculated. Why this figure is different than “First year savings” figure showed in Remuneration and Savings section in Financial Analysis, Overview chapter?
8. Please explain how you calculate savings and renumeration (in Remuneration and Savings section in Financial Analysis, Overview chapter and Cash Flow section. 

Do I understand correct that:

1. savings should be electricity you produce and consume (directly or through charging / discharging battery system) x price for electricity form the grid (variable part)
2. renumeration should be electricity you produce and sell (feed-in) to the grid x price of feed-in electricity?

It looks like PVSol is calculating Feed-in / Export tariff in Cash Flow section (or Total Payment from Utility in First Year in Remuneration and Savings section in Financial Analysis, Overview chapter) as sum of Feed-in / Export Tariff and Own Use Remuneration.

It would be really helpfull,  if you can answer me my questions regarding your calculation strategy.

Thank you in advance.

AG

[AG_0113]

Can you please answer my questions? We are trying to find out, how the program calculates the values by using battery storage system. 

We think with using BASS you save only on self-stored energy and direct consumption from PV. Also all the time energy from the grid, used for charging battery is 0.

Thank you again.

AG

[developer_fw]

Hello AG_0113,

1. Please have a look at
2. The electricity production costs is the sum of costs for the lifetime over the energy produced in the lifetime. Lifetime in this case means the period you are taking as a basis https://help.valentin-software.com/pvsol/en/calculation/financial-analysis/
3. Battery charging windows are not possible at the moment
4. Service life is the estimated time, after which the battery reaches its maximum full cycles and might be exchanged, which means there might be more investments. To estimate those costs you get this lifetime estimation.
5. Do you mean the assessment period?
6. Questions regarding Remuneration and Savings section in Financial Analysis, Overview chapter:
   1. This is the value you get for feeding energy into the grid
   2. Those are the savings of energy from the grid you don't need. This value is dependent on the start date of operation.
   3. Own Use Remuneration: In some cases you have to pay for your self-generated energy. This is taken into account.
7. Questions regarding Cash Flow section:
   1. Feed-in / Export Tariff– please explain what does it mean and how is calculated. Why this figure is different than “Total Payment from Utility in First Year” figure showed in Remuneration and Savings section in Financial Analysis, Overview chapter?
      This is the money you get for feeding in energy to the grid. The figure is different since you have to pay interest rate you set in the economic efficiency calculation window
      
   2. Electricity savings – please explain what does it mean and how is calculated. Why this figure is different than “First year savings” figure showed in Remuneration and Savings section in Financial Analysis, Overview chapter?
      Electricity savings are the costs that could be saved because less electricity had to be purchased at grid costs
8. Please explain how you calculate savings and renumeration (in Remuneration and Savings section in Financial Analysis, Overview chapter and Cash Flow section. 
   The savings are the savings of the energy you did not have to pay due to your own production and the renumeration is the value you get for feeding in your surplus energy

Do I understand correct that:

1. savings should be electricity you produce and consume (directly or through charging / discharging battery system) x price for electricity form the grid (variable part)
   This is correct
2. renumeration should be electricity you produce and sell (feed-in) to the grid x price of feed-in electricity?
   This is also correct. But there also might be the renumeration costs if you have to pay those (e.g.

It looks like PVSol is calculating Feed-in / Export tariff in Cash Flow section (or Total Payment from Utility in First Year in Remuneration and Savings section in Financial Analysis, Overview chapter) as sum of Feed-in / Export Tariff and Own Use Remuneration.

This is correct and the parameters from the cashflow table take also the parameter "annual average return on capital employed" from the financial parameters into account.

 

I hope this helps to clarify your questions. Best regards,
Frederik