A ONE-YEAR ENERGY EFFICIENCY COMPARISON STUDY BETWEEN TWO WATER HEATER SYSTEMS-ONE USING A CONDENSING TYPE GAS WATER HEATER SYSTEM AND THE OTHER USING CO2 HEAT PUMP WATER HEATER SYSTEM

Comparison of Two Gas Coolers in CO2 Heat Pump Water Heater

Performance study on solar assisted heat pump water heater using CO2 in a transcritical cycle

This study reports the numerical analyses of a CO2 transcritical cycle on solar assisted heat pump water heating system in which evacuated tube U-pipe solar collector is utilized as an evaporator. This simulation model can predict operating characteristics for moderate meteorological conditions of North Dakota. The main purpose of this work is to simulate the overall performance of the heat pum...

Experimental Study on the Performance of Water Source Trans-Critical CO2 Heat Pump Water Heater

The effect of the discharge pressure on the performance of the trans-critical CO2 heat pump with a low gas-cooler outlet temperature is experimentally investigated on a test rig of water source heat-pump water heater. The optimal discharge pressure of the trans-critical CO2 heat pump is investigated under different external operation conditions. When the tap-water temperature is low, the charac...

Energy Efficiency Improvement in a Water Heater with a Run-Around Heat Exchanger System

A significant portion of the energy consumed by home appliances that uses hot water is used for heating cold supply water. Such home appliances generally use supply water at a temperature lower than the ambient temperature. Thus, the water is normally heated from below the ambient temperature to its designed maximum temperature by the appliance, often using natural gas or an electrical heater. ...

Geyser Pump Solar Water Heater System Modeling Design Optimization

Solar thermal water heating systems reduce household energy bills by using the free solar radiation provided by the sun to heat water for residential needs. In order to eliminate the need for electricity to run a pump to drive the fluid circulation in these systems, fluid buoyancy effects can be employed to move the fluid from lower elevations to higher elevations. There are several operational...