RESIDENTIAL DOMESTIC HOT WATER CONSUMPTION ANALYSIS FOR MULTIFAMILY BUILDINGS SUPPLIED BY DISTRICT HEATING

The exact knowledge of domestic hot water (DHW) and heat consumption is necessary in the process of heat cost allocation and planning. In Hungary, heat cost allocation is based on summer months' heat demand. This method does not lead to an accurate result due to the fact that the DHW demand varies throughout the year. There are several studies dealing with consumption data analysis, but only some of them have exact estimations on DHW usage patterns the Central-Eastern European countries. In this paper the DHW consumption was analyzed in 115 "commi block" buildings, which are common in Central-Eastern Europe and Russia and are usually connected to the district heating network. The examined buildings are located in Budapest, Hungary. The installation of the monitoring system has started in December 2012. The consumption data is collected since March 2014. The DHW usage was calculated in different cases for every month: per heated area, per heated volume, and per flat. Average daily and annual data was also determined, the share of yearly DHW consumption over the months was calculated. The average daily and annual DHW consumption are 126 L per flat and 892 L per m(2), respectively. The average net heat consumption is 28.2 kWh/m(2) annually. Different DHW demand influencing factors were examined: the outdoor temperature and the residents' travelling habit is clearly influencing the DHW usage but no connection was found between the DHW consumption and economic indicators. The DHW consumption is approximately 30% higher in the winter than in the summer.