Dear Victron fans,
I once spent half a Sunday figuring out what the Victron Dynamic ESS pricing formula should look like with an Engie Dynamic contract here in Flanders.
In the meantime, I have learned that fewer than 1% of Flemish households have a dynamic contract. It shows: support is nonexistent, nobody understands anything, the app provides incorrect information…
But after a great deal of searching, I now finally have it 100% clear. I hope this helps you move forward? Please leave a comment or reply?
First, let’s take a look at the Engie contract:
When studying this contract, I learned the following:
The figures 10.809 and 6.596
Do not belong in the formula. They are the estimated annual price in euro cents per kWh that Engie used as an example/estimate at the time it prepared the tariff sheet.
It is a legal requirement for suppliers to show an estimate of what an average consumer would pay over the course of an entire year.
Units:
- The Engie contract lists everything in EURO CENT/kWh.
- Victron DESS lists everything in EURO/kWh.
- The eSPOT is in EURO/MWh.
All values, including Victron’s P value, are in euros/kWh.
All values from your Engie contract therefore need to be entered divided by 100 in Victron DESS.
Example: 1.3163 euro cents/kWh must be entered in Victron as: 1.3163/100 = 0.013163
Grid charges and taxes (from Fluvius).
These are fixed amounts per month:
- the minimum contribution for the capacity tariff (equivalent to a 2.5 kW peak, which amounts to approximately €9 per month).
- Variable distribution tariff (Fluvius Iverlek).
- Federal excise duty (average).
- Other small contributions.
- the fixed annual charge: 100.70
You pay these fixed grid charges anyway, regardless of whether you consume or inject electricity, or do neither. That is why we do not take them into account in our pricing formula.
Final formula
The overall formula is:
((espot * a ) + B) * 6% VAT
My contract lists the following values:
A value = 1.3163
B value = 0.1019
( p * 1.019 + 0.013163 ) *1.06 + 0.0106 + 0.01582
Explanation:
The pricing formula states that it is exclusive of VAT.
At the top of the contract it says: “Prices including 6% VAT”
From this, I understand that the 6% VAT only needs to be added to the formula.
P:
The eSPOT index, but now in euros per kWh; no further conversion is needed.
1.019:
the B value is 0.1019. This is the conversion that Engie applies to the eSPOT price.
The eSPOT price is in euros per MWh. Engie converts this to euro cents/kWh for your Engie contract. Converting from MWh to kWh means dividing by 1000, and converting from euros to euro cents means multiplying by 100. Together, that means dividing by 10. Hence the 0.10. Then there is an additional small charge of 1.9%.
The variable p used by Victron is already the converted EPEX price in euros per kWh (€/kWh). So no further conversion is needed here. However, the 1.9% surcharge still needs to be added. That is why we use x 1.019 here.
0.013163:
The A value of 1.3163 euro cents /1000
1.06:
The pricing formula still needs to have 6% VAT applied to it
0.0106:
Green electricity option, 1.06 euro cents/kWh = 0.0106 euros/kWh
0.01582:
Green electricity cost, 1.582 euro cents/kWh = 0.01582 euros/kWh
And for injection:
p - 0.013050
Explanation:
P:
the eSPOT index, but now in euros per kWh; no further conversion is needed.
-0.013050: the A value from the formula.
The B value is now 0.1000, or divided by 10, with no additional charges, but Victron has already performed that conversion, so nothing needs to be entered.