SOLAR FOOD DRYER

1
SOLAR FOOD DRYER
Presented by Steven Van Horn 26 April 2002
2
SOLAR FOOD DRYER OVERVIEW

• Introduction
• Requirements
• Design
• Hardware
• Software
• Results
• Sacramento, CA
• Daytona Beach, FL
• Optimization
• Summary

3
SOLAR FOOD DRYER INTRODUCTION

• Solar drying oldest method of food preservation
• Until canning developed in 18th century drying
  virtually only method of food preservation
• Dried foods have 1/3 to 1/6 bulk of raw, canned,
  frozen foods
• Dried foods have 1/6 weight of fresh food
• Dried foods increase proteins, fats,
  carbohydrates decrease vitamins
• Solar Drying Technology helps developing world
  today
• Removes moisture preventing decay and spoilage
• Allows food to be transportable
• Makes difference between waste and value of
  surplus

4
SOLAR FOOD DRYER REQUIREMENTS and GOALS

• Provide drying for variety of crops, fish, meats
• Operable in variety solar climates
• Provide portable unit
• Readily available hardware
• Small footprint
• Goal Drying Area 10X footprint
• Maintain healthy temperatures
• 130-180oF(55-82oC) Destroys bacteria, enzymes,
  fungi, eggs, larvae
• Lower than 180oF- Food begins cooking
• Reasonable cost

5
SOLAR FOOD DRYER DESIGN
Qload
It
TC2
Tr
Qu

• FACTORS
• TEMPERATURE
• AIRFLOW
• RELATIVE HUMIDITY

Qfs
Qex
Ta
TC1
T
6
SOLAR FOOD DRYER SOFTWARE DESIGN

• Calc It
• Calc Qu
• Calc TC1
• Q (mcp)c(TC2-TC1)
• Q(mcp)a(T-Tr)
• Q e(mcp)a(TC2-Tr)
• Q AcFrtaKtaIt-FrUl(TC1-Ta)
• TC1A((1/(mcp)c-1/e(mcp)a) BTa(1/(mcp)c-1/e(mcp
  )a Tr
• B(1/(mcp)c-1/e(mcp)a)-1
• where A AcFrtaKtaIt and B AcFrUl
• If Qugt0 Then Qu Qfs, Else Qfs0
• Calc Qload
• Calc Qex
• Calc Tr
• Tr Tr (Qin/(mcp)- Qout/(mcp)

7
SOLAR FOOD DRYER HARDWARE DESIGN
PV COLLECTOR
SOLAR COLLECTOR
BUILDING STICK CONSTRUCTION(8x4x12) R15.2,
320FT3 VOLUME
35 RACKS SCREENED HINGED
CAR WATER PUMP
CAR RADIATOR FAN
8
SOLAR FOOD DRYER RESULTS
9
SOLAR FOOD DRYER OPTIMIZATION
10
SOLAR FOOD DRYER OPTIMIZATION
DRYER TEMP
11
SOLAR FOOD DRYER SUMMARY

• Potential solar dryer for many applications
  crops, fish, meat
• Low efficiency (37)
• Not sensitive to gamma (30o)
• Operates within healthy temperatures
  130-180oF(55-82oC)
• Model demonstrated operable in variety solar
  climates
• Dayton, OH
• Sacramento, CA
• Daytona Beach, FL
• Solar dryer unit portable either pallet or
  mobile possibilities
• Small footprint 32 ft2(3 m2)
• Exceeded Goal of 10x drying area 368 ft2 (34
  m2)
• Reasonable cost 2200
• Solar parts 44 cost (970)
• Good Candidate for Exchange Program with foreign
  university Applies Thermodynamic, Renewable
  Energy Systems, Design of Experiments