> For the complete documentation index, see [llms.txt](https://docs.altum.ai/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.altum.ai/verduurzamen/verduurzaming-api-v2-delta-appartementen/kostenindicatoren.md).

# Kostenindicatoren

Afhankelijk van de ketenpartner die de installatie van de maatregelen uitvoert, is het mogelijk om standaardwaarden voor kosten en berekeningen te overschrijven door deze als invoer mee te geven.

### Algemene aannames 2026

<table data-header-hidden><thead><tr><th width="323.99993896484375">Naam</th><th width="82">Type</th><th width="194.333251953125">Omschrijving</th><th width="90.6666259765625">Standaard</th><th>Opmerking</th></tr></thead><tbody><tr><td>fixed_gas_price</td><td>float</td><td>From CBS, Vaste gaskosten. Transporttarief + vast leverlingstarief</td><td>360.98</td><td>In €/jaar</td></tr><tr><td>variable_gas_price</td><td>float</td><td>From CBS, Variabele prijs excl. belasting. Variabel leveringstarief contractprijs</td><td>0.5783</td><td>In €/m^3</td></tr><tr><td>energy_tax_gas</td><td>float</td><td>From CBS, Energiebelasting op gas</td><td>0.72680</td><td>In €/m^3</td></tr><tr><td>fixed_electricity_price</td><td>float</td><td>From CBS, Vaste elektriciteitsprijs. Transporttarief + vast leveringstarief</td><td>589.82</td><td>In €/jaar</td></tr><tr><td>variable_electricity_price</td><td>float</td><td>From CBS, Variabele prijs excl. belasting. Variabel leveringstarief contractprijs</td><td>0.1387</td><td>In €/kWh</td></tr><tr><td>energy_tax_electricity</td><td>float</td><td>From CBS, Energiebelasting op elektriciteit</td><td>0.11085</td><td>In €/kWh</td></tr><tr><td>fixed_heat_price</td><td>float</td><td>Van Vattenvall, tarieven 2025</td><td>760.77</td><td>In €/jaar</td></tr><tr><td>energy_tax_heat</td><td>float</td><td>Belasting op verbruikte externe warmte.</td><td>0</td><td>In €/GJ</td></tr><tr><td>variable_heat_price</td><td>float</td><td>Van Vattenfall, inclusief huur van de afleverset.</td><td>43.79</td><td>In €/GJ</td></tr><tr><td>tax_credit</td><td>float</td><td>From CBS, Vermindering energiebelasting</td><td>628.96</td><td>In €/jaar</td></tr><tr><td>feed_in_compensation</td><td>float</td><td>Opbrengst per kWh die wordt teruggeleverd aan het net.</td><td>0.1331</td><td>In €/kWh</td></tr><tr><td>feed_in_cost</td><td>float</td><td>Kosten per kWh die wordt teruggeleverd aan het net.</td><td>0.125</td><td>In €/kWh</td></tr><tr><td>fixed_solar_panel_cost</td><td>float</td><td>Jaarlijkse extra kosten van de energieleverancier als je zonnepanelen hebt.</td><td>0</td><td>In €/jaar</td></tr><tr><td>netting_percentage</td><td>float</td><td>Het aandeel van de opgewekte elektriciteit dat wordt teruggeleverd aan het net en meetelt voor de salderingsregeling.</td><td>0.65</td><td>%</td></tr><tr><td>gas_yearly_price_increase</td><td>float</td><td>Verwachte procentuele stijging van de gasprijs.</td><td>0.03</td><td>%</td></tr><tr><td>electricity_yearly_price_increase</td><td>float</td><td>Verwachte procentuele stijging van de elektriciteitsprijs.</td><td>0.02</td><td>%</td></tr><tr><td>external_heating_yearly_price_increase</td><td>float</td><td>Verwachte procentuele stijging van de prijs voor externe warmte.</td><td>0.03</td><td>%</td></tr><tr><td>term</td><td>integer</td><td>De termijn in jaren die wordt gebruikt voor de berekening van het rendement op de investering.</td><td>25</td><td>In jaar</td></tr><tr><td>discount_rate</td><td>float</td><td>Rekenrente (~inflatie) die wordt gebruikt in de berekening van het rendement op de investering.</td><td>0.04</td><td>%</td></tr><tr><td>tax_rate</td><td>float</td><td>Algemene BTW</td><td>1.21</td><td>%</td></tr><tr><td>custom_costs</td><td>dict</td><td>N.t.b.</td><td>{}</td><td></td></tr></tbody></table>

**Invoer schema**

```
"cost_indicators": {
      {
        "name": value
      }}
```

**Voorbeeld**

```
{
  "postcode": "2771DS",
  "housenumber": 87,
  "houseaddition": "",
  "cost_indicators": {
    "fixed_gas_price": 337.89,
    "variable_gas_price": 0.6595,
    "energy_tax_gas": 0.69957,
    "fixed_electricity_price": 575.76,
    "variable_electricity_price": 0.1470,
    "energy_tax_electricity": 0.12286,
    "fixed_heat_price": 760.77,
    "energy_tax_heat": 0,
    "variable_heat_price": 43.79,
    "tax_credit": 635.19,
    "feed_in_compensation": 0.1331,
    "feed_in_cost": 0.125,
    "fixed_solar_panel_cost": 0,
    "netting_percentage": 0.65,
    "gas_yearly_price_increase": 0.03,
    "electricity_yearly_price_increase": 0.02,
    "external_heating_yearly_price_increase": 0.03,
    "term": 25,
    "discount_rate": 0.04,
    "tax_rate": 1.21
  }
}
```


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