• A typical single family home uses 3,500 to 5,000 kWh a year.Backed by the source

  eIn the source · energieportal-nordheim.de

  A 140 m² single family home needs between 3,500 and 5,000 kWh of electricity a year for heating and hot water.

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• The heat pump tariff is around 28 cents per kWh.Partly backed

  sIn the source · stadtwerke-nordheim.de

  Depending on the region, heat pump tariffs are between 26 and 31 cents per kWh.

  The source gives a range of 26 to 31 cents. 28 cents is a middle value, your tariff can differ.

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• Older houses without floor heating sit at the upper end.Backed by the source

  In the source · Institut Lumen

  In unrenovated older houses the seasonal efficiency averaged 3.0, in new builds with floor heating 4.1.

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• Power costs drop by 40% after the first year.No source found

  None of the sources says this. Treat it as unconfirmed.

  This statement comes from none of the four sources. It was removed from the answer.

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