The possibility of achievement of the nZEB state of a refurbished detached house powered solely by renewable energy sources in Southern Poland

Jacek Biskupski,T Kujawa,A.A Stachel,Z Zapałowicz

doi:10.1051/e3sconf/20187001001

Abstract

This paper gives a thorough description of the two different scenarios of retrofit of an existing detached country house (with high primary energy demand) to a net zero energy building (nZEB) or near zero energy (nearZEB) by using energy form on-site RES. Using a designed piece of modelling software author pointed out two possible solutions. First one, based on a bio boiler and small on-site PV generator (on-grid) and the other based on large PV generator and three heat pumps. A 24 months test was performed in order to find out the output of both scenarios. In first period, the bio boiler delivered energy for space heating and DHW, while energy from PV was used to cover all electricity needs of the household during the 12 months testing period. In the later, the energy received from 10 kWp PV of was partly used to cover the current needs of the entire household (switchable on/off-grid system), and surplus was stored in the national electricity grid and regained later in the winter for the space heating (by a GSHP) and ventilation (ASHP) and DHW (dedicated ASHP). In both cases the system proofed the possibility to achieve the nZEB (nearZEB in first scenario) state of the household, as all (in the first near all) energy needs were covered by renewable energy produced on-site.

Highlights

The EU Directives and guidelines, stats clear that all new buildings in Europe shall be nearly or net Zero Energy Buildings from 2020 onwards
The exact definition of net Zero Energy Buildings (nZEB) and nearZEB are to be developed by members states of EU, but general definition describing them as “buildings with very low energy demand, covered mostly by energy from RES harnessed locally” which could be used in both cases
In Poland the netZEB is understand as state of zero nett energy building, where the amount of entire energy delivered to the boundary is equal the entire energy used by entire household

Summary

Introduction

The EU Directives and guidelines, (especially EPBD), stats clear that all new buildings in Europe shall be nearly or net Zero Energy Buildings (nZEB) from 2020 onwards. The exact definition of nZEB and nearZEB are to be developed by members states of EU, but general definition describing them as “buildings with very low energy demand, covered mostly by energy from RES harnessed locally” which could be used in both cases. In Poland the netZEB is understand as state of zero nett energy building (in polish “nZEB”), where the amount of entire energy delivered to the boundary is equal the entire energy used by entire household. The definition of nearZEB (in polish “niemalZEB”) is a case of a building with yearly energy demand approaching the state where all energy needs [2] are reduced beyond the state minimum demand (95 kWh/m2 year as per year 2017)

Results

Discussion

Conclusion