Energy Saving
After twenty years of constant evolution, improving our system, after several hundred realisations, houses built according to it surpass several times the most demanding standards for energy efficiency. Demand for primary energy for houses in Krzywa Iwiczna ranges from 30 to 40 kWh/m2*year, for houses in Kędzierówka 20-30 kWh/m²*year. Standard reference level is 150 – 180 kWh/m²*year. These are probably the warmest houses built in series in Poland and the first world league. We want to be the leader.
In our own laboratory, we conduct a series of research works aiming at further reducing the energy needs of our houses. The research are realised together with Warsaw University of Technology (especially with the Institute of Thermal Technology) and with the Institute of Technology in Delft, the Netherlands. Now, we realise the program of going below the level of 15 kWh/m² (from where passive houses start) while maintaining prices of affordable houses. We will probably achieve the goal in the next estate. The next program will involve building houses independent of the state power grid.
Sources of energy savings:
- 20% urban planning - compact, economical buildings;
- 5% architecture - compact solids, orientation to the sun: of the functional arrangement of houses, arrangement and size of glazings;
- 15% skeletal structure, very good thermal insulation;
- 20% central heating system, based on biofuel - fireplace with a water jacket cooperating with the water heat tank;
- 15% devices for recovering heat from wastewater, cooperating with solar collectors;
- 10% - external partitions with very low diffusion resistance (gas permeation). Natural gas exchange through the partitions significantly reduces the need for house ventilation.
When building a highly energy-efficient houses the most serious problems do not lie in the area of technology, but in the area of economics and psychology. How to design a house that would not look like a reactor or "a machine for living"? Therefore, we believe that a harmonious combination of all the necessary elements is our main achievement. Probably, an important role for the acceptance of our houses plays a moderation in exposing technology and modernization, and balancing the cultural areas by traditional architecture and urbanism.
