Wind electric heating and cooling system for an office application

The winter and summer air-conditioning demands of buildings strongly affect energy requirements in the civil sector. Therefore, it can be interesting and effective to search alternative solutions in this field, with the aim of saving primary energy and reducing the related greenhouse gas emissions. Systems activated by renewable energy sources could achieve both of these aims. Plants exploiting solar energy are widely studied. In this paper, an air-conditioning system driven by the electricity available from small-scale wind turbines for an office building located in Naples is analysed. Assessments with two kinds of wind turbines (5-5.5 kW), vertical and horizontal axis, are performed, also considering the coupling with one and two identical wind generators. In order to better use on-site the electricity a parametric study is proposed taking into account different battery storage system sizes (3.2-9.6 kWh). Energy and environmental performance have been evaluated through dynamic simulations, comparing the wind-activated plant with a conventional one, fed by electricity taken from the external grid and natural gas. A primary energy saving and a carbon dioxide emission reduction of 52% and 47%, respectively, are achieved in the best case. The electricity taken from the power grid reduces with the battery storage size and when two turbines are considered. With respect to generated electricity used on-site in the best case (one vertical axis wind turbine and 9.6 kWh battery capacity) 83.1% of the production fed the load, whereas, the maximum share of the load met by the wind generators is 25.1%, this takes place when two vertical axis wind turbines and 9.6 kWh battery storage are considered.