Besides the Solar and Heating Calculator, the ZEV Calculator is part of the Eturnity calculator repertoire. And the ZEV model (association for self-consumption) is becoming more and more of a trend in Switzerland, which we are also noticing at Eturnity.

Accordingly, we have given our Eturnity ZEV Calculator an update with many new functions:

1. Adjustment of the calculation basis for ZEV Calculator

Within a ZEV, the electricity producer can sell the electricity directly to the electricity consumer, e.g. the tenant. This saves costs, because the price of the self-produced electricity is usually lower than the externally purchased electricity. The profit can be shared between the parties.

What is new now:

  • It is possible to split the savings between the parties (e.g. landlord and tenant) with regard to the electricity production costs (compared to the external electricity purchase).

→ No tax savings are included in the calculation.

→ The calculation basis is in accordance with the “Guidelines for self-consumption” (in German) and the “Calculation of production costs of photovoltaic systems for ZEV” by Swissolar (in German).

2. introduction of a ZEV retrofit option

  • Existing PV plants can now be calculated as ZEV plants for a future merger.

→ This is made possible by the retrofit option in the new ZEV Calculator, which optionally converts a digital upgrade and modernisation of the existing PV system into a ZEV.

3. revision of the existing ZEV Calculator

The Eturnity ZEV Calculator has been additionally revised in terms of use and appearance:

  • The ZEV systems are added and defined in the Eturnity Expert library in the menu item Solar Calculator.

→ I.e. These are mapped analogously to the heating and solar calculator solutions and ZEV-specific components can be recorded.

  • The income over the lifetime of a PV system from the perspective of an investor is made visible and is divided into the following 3 components:

→ Income from the electricity cost savings of the ZEV

→ Income from the financing of the PV system incl. ZEV

→ Income from charging the production costs (without financing costs) to the ZEV participants.

4. introduction of own PDFs in the ZEV Calculator

Until now, it was not possible to create your own PDF documents in the ZEV Calculator; we have now changed this.

What does the PDF document contain?

  • Autonomy & Independence
  • Explanation of the ZEV model
  • ZEV economic efficiency
  • CO2 balance
  • Tenant information sheet and next steps

→ The PDF is also available for the retrofit version

Test the ZEV Calculator here

We answer your questions

If you have any questions about the ZEV Calculator updates, please feel free to contact our consulting team. We look forward to presenting the innovations to you:

Tel.: +41 81 511 64 64

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Bettina Enser

Bettina Enser is responsible for marketing and communications at Eturnity AG. She provides insights into topics related to the marketing of renewable energy systems. If you have any questions regarding the article, please contact