Energy, environmental and economic analysis of electric vapour compression and gas driven absorption heat pumps for single-family houses

Marcello Aprile,Rossano Scoccia,Tommaso Toppi,Giorgio Villa

doi:10.1051/e3sconf/202131206001

Abstract

The aim of this paper is to compare energy consumptions, CO2 emissions, and operative costs of condensing boilers, electric vapour compression heat pumps and gas driven absorption heat pumps to provide space heating and domestic hot water. The analysis is performed for 140 m2 single-family houses in five different Italian cities whose envelope features depend on the location. For each location, two different envelope conditions are considered. The first one is a non-insulated building, while the second one is the same building, but an external thermal insulation is added on vertical walls and roof. To avoid internal renovation, radiators are maintained as emission system. Combined dynamic simulations are performed to appreciate building and system interactions. A 6 second time step is set to evaluate properly interactions and the DHW profile demand. In addition, the GHP dynamic model is a grey box model experimentally validated. The results show that electric vapour compression heat pumps reach the highest non-renewable primary energy savings (>32%) compared to condensing boilers, but their operative costs are higher due to the higher specific cost of electricity in Italy. Gas driven absorption heat pumps achieve a lower consumption reduction than electric heat pumps (>22%), but they have also the minimum operative cost among the three technologies.

Highlights

European buildings represent about 40% of the overall EU28 energy consumption and 36% of greenhouse gas emissions [1]
Electric vapour compression heat pump: (EHP) gives the possibility to obtain a reduction of non-renewable primary energy consumption between 32% and 46%, while gas driven absorption heat pump (GHP) is able to achieve savings between 22% and 28%. - For the “Renovated Building”, the energy consumptions are strongly reduced compared to the previous ones due to the envelope insulation
Results show that the non-renewable primary energy saving gaps between GHP and EHP are different in Old and Renovated Buildings

Summary

Introduction

European buildings represent about 40% of the overall EU28 energy consumption and 36% of greenhouse gas emissions [1]. For countries with a capillary gas distribution infrastructure, the gas driven heat pump provides the possibility to use renewable energy avoiding a load shift from natural gas to electricity, as it would be required installing electric vapour compression heat pumps. Both GHP and EHP are not able to produce domestic hot water instantaneously as boilers, a water storage is required. The aim of this paper is to compare the non-renewable primary energy consumptions, CO2 emissions, and operative costs of condensing boilers, electric vapour compression heat pumps and gas driven absorption heat pumps to provide space heating and domestic hot water. An additional improvement, compared to previous works [3] [4], is the use of combined simulations of building and system to appreciate the interaction between them

Objectives

Results

Conclusion