astra with photovoltaics
Everyone planning to build a new house or to renovate an old one has to opt for a heating system. There is a multitude of different possibilities. In terms of investment and operation costs, the astra natural stone heating in combination with a photovoltaic installation is an advantageous alternative to other heating systems.
The energy generated by the photovoltaic installation is not only used for the heating but also for the household electricity. Thus, when looking at the energy costs, the total energy demand has to be taken into account that means energy for household electricity, heating and warm water.
In the following example we have calculated the investment and operation costs of an astra natural stone heating combined with a photovoltaic installation.
The calculation is based on a newly built family home with 146 sqm of heated surface.
All prices including 19% VAT
|astra natural stone heating, including installation,
ready to use
|Warm water, 300 l stand-alone water tank,
ready to use
|Photovoltaic installation, 5.35 kWp, ready to use||10.000 €|
Our calculation of the total energy costs for a newly built family home with 146 sqm of heated surface is based on the following values:
|Average heat requirement||50 W/sqm|
|Total heat requirement||7.28 kW|
|Annual energy requirement for heating and warm water||8,760 kW/h|
|Annual energy requirement for household electricity||3,500 kW/h|
|Costs per kW/h for heating electricity (special rate HT/NT)||0.20 € incl. VAT|
|Costs per kW/h for household electricity||0.26 € inkl. VAT|
|Buyback price per kW/h||0.124 € incl. VAT|
Requirement heating, warm water and
Covered by PV installation
Electricity costs per month
|January||4.16||129||1,757||7 %||342 €||396 €|
|February||8.82||247||1,758||14 %||317 €||396 €|
|March||14.39||446||1,241||36 %||170 €||266 €|
|April||20.83||625||892||70 %||59 €||196 €|
|Mai||21.48||666||741||90 %||17 €||166 €|
|June||23.40||702||292||Überschuss||-51 €||76 €|
|July||21.71||673||292||Überschuss||-47 €||76 €|
|August||19.16||594||552||Überschuss||-5 €||128 €|
|September||15.80||474||741||64 %||60 €||166 €|
|Oktober||9.90||307||991||31 %||149 €||216 €|
|November||5.17||155||1,241||12 %||234 €||266 €|
|December||3.32||103||1,758||6 %||347 €||369 €|
|Per year|| 5,121 kW/h
|| 12,256 kW/h
||1,592 €||2,663 €|
With a 5.35 kW/p photovoltaic installation it is possible to save approximately 40 % of the annual energy costs. An additional energy storage device or a bigger PV installation will even increase the savings.
Comparing the annual energy costs of 1,600 € for household electricity, heating and warm water as well as the low additional costs (operating costs) with other heating systems and acting on a 20 years run-time, the astra natural stone heating system combined with a PV installation is one of the most advantageous, future-oriented and healthiest heating systems on the market.