Efficient Heat Generation for Resorts

Abstract

This study compares the energy efficiency of two processes covering the thermal energy demand of a swimming pool: a combined heat and power (CHP) unit on the one hand, and a heat pump with internal combustion engine on the other hand. The thermal energy demand of the swimming pool was 1438 kWh per day (78% heating the pool and 22% providing hot water for showers), owing to temperate climate in the city of Toluca in central Mexico; a mean annual temperature of 13.5 °C (10.5 °C in January and 15.7 °C in June) offers a large potential of renewable thermal energy stored in the atmosphere. Its utilization in heat pumps driven by thermal combustion engines can provide energy below 60 °C; this temperature level provides hot water for showers while a lower temperature level of about 40°C heats up the pool water and swimming hall. Depending on outdoor temperature, which defines the load for the units, the efficiency in terms of total primary energy consumption is better for the CHP solution (100% and 80% load) and is better for the heat pump in the case of a 57% load. The energy losses for the CHP unit on-site are equivalent to half the losses caused by extraction and distribution of natural gas under current circumstances in Mexico. The results provide a decision tool.

Cogeneration Process Technical Viability for an Apartment Building: Case Study in Mexico

“…In the "showers" stage, hot water is used in the apartment's showers, washing machines, as well as bathroom and kitchen sinks. A heat exchanger (21; center-left area Figure 10) is used to obtain the hot water which is fed with saturated steam from the evaporator of the recovery boiler to achieve the hot water flow required for the building at 60 • C. Each process shaft (13,18,22,41,42) represents the hot water requirement for a section of the building, according to the number of people living in an apartment. The "hot air" stage is shown, which meets the needs of hot air by using a heat exchanger, where the hot water flow from the recovery boiler comes into contact, countercurrent wise, with the air that heats up from room temperature conditions on to 23 • C. Flows are separated per building and thereafter, the processes (30, 54, 56, 57 and 92) are distinguished according to living/dining room volume of <80 m 3 and between 80 and 144 m 3 .…”

“…A housing complex in central Mexico is presented as a case study. Weber et al [41] compares the energy efficiency of two processes covering the thermal energy demand of a swimming pool: a CHP unit on the one hand, and a heat pump with internal combustion engine on the other. The energy losses for the CHP unit on-site are equivalent to half the losses caused by extraction and distribution of natural gas under current circumstances in Mexico.…”