Adaptive Maze Finding a project through a changing maze of complications Project Team: Krista Miller Sohaib Hasan John Helme

Excess Thermal Energy From Solar Panels Primary Problem: Solar panels installed in the Alternative Energy Laboratory can be damaged if heated to temperatures above 180° F. Secondary Problem : The alternative Energy Laboratory can be come uncomfortably warm on hot summer days.

Solution Overview Energy Dumping System: –Dissipate excess heat by routing the solar panel output through underground coils. Energy Conversion System: –Dissipate excess heat by converting it to other forms of energy: Mechanical Energy – Stirling Engine Electrical Energy – Seebeck device Energy Blocking System: –Cover solar panels to reduce energy input.

Energy Dumping System Install valves and pipes to allow the output of the solar panels to run through underground pipes

Energy Dumping System Advantages –System is always on. –Few components. –Convection currents maybe used to allow the system to work without motors, sensors or switches. Disadvantages –Excess energy is lost –To simple to earn an acceptable grade. –Excavation and plumbing maybe to expensive.

Energy Conversion Systems How much excess energy is available? Q = cm(T 1 -T 2 )Q= Heat = energy c= specific heat c water = 4.186j/g°C For one kg of waterT1 = 90°F= 32.2°C Q=3669kJT2 = 180°F=90°C

Energy Conversion Systems How much power is being added to the system? Panel Characteristics Quantity10 Area2.96m 2 EfficiencyUp to 70% Solar insolation for Vermont = 400W/m 2 Power new = Quantity * Area * Efficiency * Solar insolation = 8288W

Energy Conversion– Stirling Engine The stirling engine uses a temperature differential cause gases to expand and compress. This expansion and compression is used to drive one or more cylinders.

Stirling Engine Advantages –High efficiency engine –Direct conversion from thermal energy to mechanical energy –Mechanical energy could be applied to cooling the facility Disadvantages –Very complicated and experimental –May require higher temperatures to work without using special gases –May not dissipate enough energy to keep the panels cool

Energy Conversion –Seebeck Device A voltage is created when there is a temperature difference between two different metals or semiconductors. V = (S B -S A ) * (T 2 -T 1 ) V = Voltage generated S = Thermoelectric Power Coefficient for materials A and B T = Temperature at junctions 1 and 2

Seebeck Device Seebeck Power Generation Module Output T 1 = 150°C, T 2 = 50°C5.8 W Price (each)$43.95 Approximate cost to generate 50W with a temperature difference of 50° $880.00

Seebeck Device Advantage –Thermal energy is converted to electrical energy –Electrical energy can be applied to other applications in the facility Disadvantage –Expensive –Will not dissipate enough energy to keep solar panels cool

Energy Blocking System Solar panels will be covered before the critical temperature of 180°F is reached. Covers will stop the panels from continuing to heat.

Energy Blocking System Advantages –Definitive control of solar panel heating process –Uses electro- mechanical devices and systems. Disadvantages –Potential energy is not acquired

Solution Summary SolutionResolves Problem Economically Feasible Conserves Energy Uses Electro- mechanical systems Dump heat into ground YesNo Sterling Engine No – limited heat dissipation UnknownYes Seebeck Device No – limited heat dissipation NoYes Energy Blocking Yes NoYes

Heat Blocking System Overview Water Temperature Sensor Motor to raise/lower panel Panel Assembly Controller Panel Setting Sensor

System Control Panels Idle Start Panels Down Incremental Raise Panels Incremental Lower Panels Temp >160° and Temp > previous Temp and Time Interval complete Temp <150° and Temp <previous Temp and Time Interval complete