Seed Storage

Seed StorageAnthony Re, Kevin Zeng

Objectives Statement• Families in Honduras do not have seeds for

their own gardens• No way to store seeds for long durations• Objective: Create an effective storage

unit for long-term seed storage and create a method of managing humidity

Storage Requirements• Low Temperature and Humidity• General relationship:• F° + Relative Humidity <=100

• Goal: below 40 F and 60% RH

Idea Development Started out with many ideas

Vacuum sealed jars Refrigeration Silica gels Oxygen absorbing packets 10 foot deep crawlspace for storage More expensive ideas

DIY Dehumidifieraterials• 2 tier system• Top layer absorbs water from air using dissicant (rock

salt, charcoal)• Bottom layer collects water and should be dumped

regularly

Final Design• Refrigerator Available• Use in conjunction with Jar/Duct

Tape and DIY Dehumidifier

DIY dehumidifier trays.

Issues Encountered• 1 week into the project, Larry, our contact switched us to a

different refrigerator that was smaller

• Original Refrigerator Dimensions Freezer compartment-H-14", W-25", D-14"Refrigerator compartment H-42", W-26", D-20"

• New Refrigerator Dimensions Freezer compartment-H-12", W-13", D-13"Refrigerator compartment-H-30", W-13", D-13“(Desiccator Barely fit 12.5”x12.5”)

• It did not work as efficiently

Test 1 : Humidity and Temp.

• Original Refrigerator was perfect• New Refrigerator had much higher humidity and temperature

o Needed to request for original refrigerator

Day Temperature (°F) Humidity (%) Total Fridge1 38 15 532 38 17 553 37 13 504 38 15 535 39 16 55

Day Temperature (°F) Humidity (%) Humidity in Jar (%) Total Fridge Total Jar1 51 55 33 106 842 52 52 35 104 87

OriginalRefrigerator

NewRefrigerator

Test 2 : Power Usage

• Used outlet power meter• Power factor - Power/VA (apparent power)

o 0.63 is normal for appliances• ~60 USD/Yr

o A bit expensiveo Based on 0.25 USD/kWH

Voltage Power Factor VA Power (W) USD/Day USD/Wk USD/Mo USD/Yr

109 0.63 180 112 0.15 1.125 4.85 59.125

Outcome/Conclusion• Ask to use original refrigerator

o Accepted so there should be no problem in seed storage• Successful project

o Effective technology Cooling + desiccation in one device

• Would have been much more difficult for a Honduran familyo No refrigeratoro No power (even though it is very cheap)

Materials/Costs

• Would be much more costly if refrigerator weren’t available• Upkeep cost ($60 USD/Yr.) is a lot

o Average refrigerator is 400W o 150 W solar panel is $150, need 4o Most efficient is still to buy electricity

Material Obtained In Cost (USD)Plastic Trays

(2) US 20

Charcoal Honduras providedRefrigerator Honduras provided

Jars Honduras providedDuct Tape Honduras provided

Hygrometer 8Total US 28

Recommendations1. Power the refrigerator using solar or

alternative energy source

2. Use smaller refrigerator if space is too large

3. Test to make sure seeds will survive a whole year

Acknowledgements• Roger Dzwonczyk (daily support)• Miriam Cater (daily support)• Larry Overholt (created opportunity for this project, guidance and

foreign liaison)• Angie Overholt (created opportunity for this project, guidance and

foreign liaison)• Dr. John Merrill (created opportunity for this project)

Questions?