Solar Energy CollectionMSD 8404 01/11/08

Solar Pasteurizer

Solar Energy

Water

Collect Solar Energy

Convert to Heat

Transfer Heat to Water

Store Input Water

Receive Heat

PasteurizeHeat Back

into System

Output Pasteurized

Water

Functional Diagram for P0804 Solar Pasteurizer

Identified Sub-Systems

Pasteurize

Heat Back into System

Collect Solar Energy

Store Input Water

Convert to Heat

Flow Control

Heat Transfer

Transfer Heat to Water

Receive Heat

Solar Collector

Heat Recovery

Solar Collector Concepts

• “Flat Plate” Collectors– First Gen Type– Various Serpentine Patterns– Coiled Tube

• Evacuated Tube Collector• Parabolic Mirror and Pipe

Flat Plate Collectors

Evacuated Tube Collectors

Parabolic Mirror Collection

Collector Concept Selection Matrix

Collector ConceptsA B C D

(reference)

Segment First Gen Serpentine Flat Plate Black Coil Evac Tube

Selection Criteria Weight Rating Notes Wtd Rating Notes Wtd Rating Notes Wtd Rating Notes Wtd

Thermal Efficiency 30% 3 - 0.90 4 - 1.20 2 - 0.60 5 - 1.50

Material Cost 50% 3 - 1.50 3 - 1.50 5 - 2.50 2 - 1.00

Safety 10% 5 - 0.50 5 - 0.50 5 - 0.50 3 - 0.30

Maintenance 10% 4 - 0.40 3 - 0.30 4 - 0.40 5 - 0.50

Total Score 2.90 3.20 3.60 2.80

Rank 4 2 1 3

Continue? Yes Yes No

Flow Control

• Automotive Thermostat (First Gen)– Residential radiator thermostatic valves too expensive

• Multiple Thermostats• Manual Valve• Electronic on/off• Density• Thermal Orifice• Bimetallic strip

Flow Control Concept Selection Matrix

A B C

(Previous Design

Automotive Thermostat Multiple Thermostats Manual valve

Selection Criteria Weight Rating Notes Wtd Rating Notes Wtd Rating Notes Wtd

Reliability 35% 1 - 0.35 3 - 1.05 3 (If operated correctly) 1.05

Ease Of Use 15% 5 No Interface 0.75 5 No Interface 0.75 1 Constant Attention 0.15

Cost 25% 5 - 1.25 4 - 1.00 5 - 1.25

Safety 5% 5 - 0.25 5 - 0.25 3 - 0.15

Maintenance 15% 4 - 0.60 4 - 0.60 5 - 0.75

Warm-Up Delay 5% 2 - 0.10 2 - 0.10 3 - 0.15Total Score 3.30 3.75 3.50

Rank 5 3 4Continue? Yes No

D E F G

Electronic on/off Density Thermal Orifice Bimetallic strip

Selection Criteria Weight Rating Notes Wtd Rating Notes Wtd Rating Notes Wtd Rating Notes Wtd

Reliability 35% 5 - 1.75 4 - 1.40 4 Needs pre-filter 1.40 4 - 1.40

Ease Of Use 15% 5 No Interface 0.75 5 No Interface 0.75 5 No Interface 0.75 5 - 0.75

Cost 25% 1 Must be Overcom 0.25 3 - 0.75 5 - 1.25 3 - 0.75

Safety 5% 3 - 0.15 5 - 0.25 5 - 0.25 5 - 0.25

Maintenance 15% 5 - 0.75 4 - 0.60 2 - 0.30 1 - 0.15

Warm-Up Delay 5% 4 - 0.20 2 - 0.10 3 - 0.15 4 - 0.20Total Score 3.85 3.85 4.10 3.50

Rank 2 2 1 6Continue? Yes Yes On Research No

Heat Recovery

• First Gen (flat plate integrated heat exchange)• Coiled tube in tube• Soldered Tube• Straight tube in tube

Heat Recovery Concept Selection Matrix

Heat Exchanger ConceptsA B C D

(reference)Segment First Gen Coiled tube in tube Soldered Tube Straight tube in tube

Selection Criteria Weight Rating Notes Wtd Rating Notes Wtd Rating Notes Wtd Rating Notes Wtd

Thermal Efficiency 30% 3 - 0.90 4 - 1.20 3 - 0.90 4 - 1.20

Material Cost 50% 2 - 1.00 3 - 1.50 4 - 2.00 3 - 1.50

Safety 10% 5 - 0.50 5 - 0.50 5 - 0.50 5 - 0.50

Maintenance 10% 2 - 0.20 4 - 0.40 4 - 0.40 4 - 0.40Total Score 2.40 3.20 3.40 3.20

Rank 4 2 1 3Continue? Yes Yes Yes

Concepts

Dual-Valve Convective Loop

Serpentine w/Pipe within Pipe

Spiral Black Tube Collector w/ Braided HX

Flat Plate w/Integrated HX and Dual Valve

Batch System: Reused Plastic Bottles

Final Concept SelectionA B C

Selection Criteria Weight Rating Notes Wtd Rating Notes Wtd Rating Notes WtdReliability 20% 2 0.40 2 0.40 2 0.40Ease Of Use 10% 3 0.30 3 0.30 3 0.30Cost 25% 3 0.75 2 0.50 1 0.25Safety 25% 2 0.50 3 0.75 3 0.75Maintenance 15% 2 0.30 4 0.60 3 0.45Warm-Up Delay 5% 2 0.10 3 0.15 4 0.20

Total Score 2.35 2.70 2.35Rank 5 3 4

Continue? Yes No

SPHINX (Previous Design)

Convective loop w/ divorced heat exchanger

parabolic collector tube within a tube

D E F G

Selection Criteria Weight Rating Notes Wtd Rating Notes Wtd Rating Notes Wtd Rating Notes WtdReliability 20% 3 0.60 3 0.60 2 0.40 3 0.60Ease Of Use 10% 3 0.30 3 0.30 4 0.40 1 0.10Cost 25% 2 0.50 2 0.50 4 1.00 1 0.25Safety 25% 3 0.75 3 0.75 3 0.75 4 1.00Maintenance 15% 2 0.30 3 0.45 3 0.45 3 0.45Warm-Up Delay 5% 2 0.10 3 0.15 3 0.15 1 0.05

Total Score 2.55 2.75 3.15 2.45Rank 2 2 1 1

Continue? Yes Yes Yes No

Flat Plate, Dual valve, integrated heat

exchangerSerpentine, Pipe Within

PipeCoiled Tube, Braided

Heat exchanger Batched Bottles