Low Temperature Space Heating Systems

1. Low Temperature Space Heating Systems Dr. Evgueniy Entchev CMX 2012 Learning Forum March 22, 2012

2. Drake Landing Solar Community • Largest Solar Community project in North America • Location Okotoks, Alberta - 20 km south of Calgary • Subdivision of 52 homes space and water heated by solar

4. End-user space heating utilization system The designed system must be able to : • Provide comfort while utilizing renewable source • Work with fluid incoming temperature from 65oC – 35oC • Provide heat recovery from the exhaust house air HW in Supply Plenum HW out Tw1 Tw2 Ta1 Heating Coil Ta7 Return Plenum Ta2 Blower Ta6 Ta5 Preheated air temperature House exhaust air HRV Ta4 To outside Fresh air Ta3

5. Air Handler To achieve the required versatility - vary 3 parameters • Air flow • Water Flow • Water Temperature

6. Design of low temperature AH • Ability to vary the air flow as a function of the incoming fluid temperature • Use baffles to provide an ~ even air distribution over the coil • Use high efficient blower motors - ECM to save energy • Re- design the heating coil to get as max heat as possible at given air flow velocity

7. Design of low temperature AH • Use highly insulated stratified tank • Use high efficient DC water pumps • Vary the water flow as a function of the outdoor temperature to preserve the stratification in the tank

8. 2 1 6 1 2 3 4 5 8 7 Stack Fuel Flow Stack Temp. Stack Current Stack Air Flow Stack Air Inlet Temp. Burner Fuel Flow Burner Combustion Temp. Stack Voltage Burner Air Flow Burner Air Inlet Temp. Input Layer (8 inputs) 1 Hidden Layer (10 neurons) Output Layer (2 outputs) Design of low temperature AH • Use at least 3 control set points 35oC, 50oC, 65oC • Use AI learning algorithms to optimize the system operation and comfort delivery • Utilize as many modulating devices

10. Thank You!