Hybrid Solar Dryer

Mosquito net cover

Lower cabinet, will be closed completely

Upper cabinet - 5 shelves

Solar collector

Turbine Vent

36 in

40 in

48 in

20 in 93 in

4.8 in 8 in

48 in

48 in

Clear plastic top installed at 18 degrees

Corrugated plastic painted black and installed on 9 degrees

Solar vent fanMust be imported

Total cost in Haiti: About $2200

Haiti 1st Solar Dryer Specs

Materials: Galvanized sheet metal sides, angle iron for reinforcement, metal screws for fastening. Sheet metal edges are finished to be dull, so they are not a sharp hazard.

The solar collectors have a clear plastic top and an additional layer in the middle, made from corrugated metal painted black installed at an angle of 9 degrees, sloping up towards thecabinet.

Built in modular form, so that the unit can be disassembled and moved easily. The 3 solar collectors are to be built separate from the cabinet and the cabinet built in 2 parts (upper and lower).The roof is to be built as a separate module too. Each module is to have handles foreasy carrying. The roof, upper cabinet, lower cabinet and solar collector modules are to havethe handles. 2 handles on each side of each module.

Inside the cabinet make 5 shelves, equally spaced in the vertical direction, using angle iron rims and galvanized mesh. The shelves should be sturdy and are to be non-removeable.

The cabinet is to have 2 doors in the upper cabinet that open side by side. Note, this is different than the door shown in the designs below. We are open to other door design ideas, if you feel there is a better way to make a durable access. The doors should close tightly.

Add a clear plastic window at “head level” in both doors. Fabricate a “pocket” behind one of the windows, where an oven thermometer or similar gadget could placed to measure the inside temperature and humidity and could be viewed without opening the doors.

The roof will have a solar fan (to be provided) and a chimney or turbine vent. The solar fan is to be installed on the south facing side of the roof. The side opposite of the cabinet doors.

C:\Users\S Michael McLaughlin\Dropbox\TTFF\Solar Dryer\BUILD THE HYBRID SOLAR DRYER.docx

TTFF SOLAR DRYER SPECSDesigned by Mike McLaughlin, Trees That Feed Foundation

IMPORTANT INSTRUCTIONS

April, 2019

CONSTRUCTION:

DO:

Build in modules. Six modules (3 collectors, lower cabinet, upper cabinet, roof).

Use 26 gauge galvanized sheet metal, with a metal frame for strength.

Each unit needs to be strong and rigid.

Fasten handles to each module, for easy handling.

Avoid sharp edges on the metal—severe injuries are possible at the metal edges.

Collector top angle is 18 degrees; middle layer (the corrugated layer) 12 degrees approximately.

Add a chimney or rain-proof vent, to supplement the solar fan.

Need doors at the back of both the lower cabinet and upper cabinet. Doors need to close snug.

Allow the doors to be locked. (Remember doors on the back, that is, North side of cabinet.)

Mosquito mesh at intake of solar collectors, to keep out insects.

Use silicon seal or tape along edges to make the unit airtight and watertight.

Estimate your costs in advance. TTFF can subsidize a LIMITED NUMBER of these.

Create and price out a parts list:

• 11 sheets 4’x8’ galvanized sheet metal

• Angle bars to fasten sheet metal together

• 3 sheets of clear plastic

• 3 sheets of corrugated galvanized sheet metal, painted black

• Hardware and accessories

• Solar fan and certain items may need to be imported

Very detailed engineering drawings are located at

https://www.dropbox.com/sh/t6pavktbqyn0mhl/AAA1JAKhFIT9yWyZ_K8OZY2Ka?dl=0

Note: the height of the lower cabinet module is revised to 40 inches.

DON’T:

Don’t build all in one piece.

Don’t change the design without prior discussion. Our experience has shown that every design change

has reduced the performance of the dryer.

Don’t insulate the cabinet.

C:\Users\S Michael McLaughlin\Dropbox\TTFF\Solar Dryer\BUILD THE HYBRID SOLAR DRYER.docx

Don’t disconnect the solar fan. You need air flow to move moisture out of the cabinet.

Don’t build your own shelves. Perforated aluminum trays are cheap. Only build support for trays

(suggestion: chicken wire or chain link wire).

Don’t use wood to construct. Although it’s lower cost initially, wood deteriorates with time, harbors

bacteria and is generally not food safe.

OPTIONAL:

5 shelves in upper cabinet, instead of four.

2 doors at the back, instead of one larger door.

Doors should be lockable to avoid petty theft.

OK to insulate the floor of each solar collector.

A clean-burning kerosene or propane stove/heater can be located in the lower cabinet, for use on

cloudy or rainy days.

Paint upper cabinet black, to absorb more solar heat.

INSTALLATION:

Chosen location must be sunny all day. Avoid shade.

Assemble the modules starting with the lower cabinet, then upper, then roof. Align East-West.

The modules must be fastened together securely.

The middle collector should face South (in the Northern Hemisphere).

The roof unit is square; install so that the solar fan faces South (if you are in the Caribbean, or in the

Northern Hemisphere)

Level the unit; prop up where necessary if the ground is not level.

Use tape or silicon sealer to make the cabinet airtight and watertight.

Take the roof and upper cabinet off, if a storm is approaching.

IN USE:

A full load is approximately 80 to 100 pounds of fresh fruit.

Shred or slice the fruit, spread out in flat perforated pans.

Agitate the fruit after one or two hours.

In full sun the fruit should dry in 4 to 6 hours.

C:\Users\S Michael McLaughlin\Dropbox\TTFF\Solar Dryer\BUILD THE HYBRID SOLAR DRYER.docx

PHOTOS OF ACCESSORIES:

Solar fan 365 cfm

Approx. US$65.00

Turbine vent (adjusts to vertical) 12”

Approx. US$65.00

Perforated bun pan, 18” x 13”

Approx. $US4.00

PARTS LIST FOR HYBRID SOLAR COLLECTOR

SOLAR COLLECTORS (3)

Part No.

Dimension

inches

(approx.) Description

1 48 x 92" Galv. Sheet metal; collector floor

2 92" side bar

3a 48" side bar

3b 48" side bar

4a, b, c, d 39" vertical bar

5 9" vertical bar

6 9, 39, 92" trapezium shape side panel

7 94" inner bar

8 46" x 94" corrugated sheet metal painted black

9 96" side bar

10 48" cross bar

11 48 x 96" clear plastic cover

LOWER CABINET

12 48 x 48" cabinet base

13 48" w 40" h the detailed engineering drawings are slightly different

14 48" side bar

15 40" the detailed engineering drawings are slightly different

UPPER CABINET

16 48 x 38" cabinet front panel

17a, b, c, d 38" side bar

18 48 x 38" cabinet side panel

19 48" shelf holder

27, 28, 29 magnets (?)

ROOF

20 48 x 10, 2" roof side panel, modified triangle shape

21 25" roof side bar

22 25" roof side bar

23 50 x 28" roof top solar fan

24a, b 50 x 28" roof top chimney, turbine vent

25 20" chimney shaft

26 6 x 2" chimney cap, conical

C:\Users\S Michael McLaughlin\Dropbox\TTFF\Solar Dryer\PartsListSolarDryer

Solar Collector, Assembly Guide:

Step 1) Secure Part 1 to Parts 2, 3a and 3b at the locations circled

Step 2) For Solar Collectors 1 & 3: Align Parts 4a, 4b and 5 with the assembly in Step 1 For Solar Collector 2: Align Parts 4c, 4d and 5 with the assembly in Step 1.

Step 3) Secure Parts 6 to Parts 4 and 5 at the locations circled

Step 4) Secure Parts 7 with the previous assembly at the locations circled. Note: Some of the previous screw locations in the previous step will be reused.

Step 5) Rest Part 8 on the assembly in Step 4 such that it rests on Part 5.

Step 6) Secure Parts 9 to Parts 6, 5 and 4 in the previous assembly at the locations circled.

Step 7) Secure Parts 10 and 11 to the assembly in Step 6 at the locations circled.

Step 8) Secure Part 12 to the assembly in Part 7 at the locations circled. Note: At the interface between Part 12 and Parts 10 caulk will be needed to create a seal.

Parts needed: ___ ¼-20 screws (length ¼”) and nuts

Lower Cabinet Assembly Guide: Step 9) Attach Part 12 to Parts 3a and 3b at the locations indicated (12 locations)

Step 10) Attach Parts 13 and 14 at the locations indicated. Set aside for later attachment.

Step 11) Align Parts 15a, 15b, 15c and 15d with the assembly in Step 10.

Solar Dryer Assembly: Step 12) Attach the assembly from Step 10 to the assembled solar collectors 1, 2 & 3 at the locations indicated.

Step 13) Align the assembly in Step 11 with the solar dryer assembly. Connect at the locations indicated and repeat for 15a, 15b, 15c and 15d.

Upper Cabinet Assembly Guide: Step 14) Align Parts 17a, 17b and 16 as shown and secure at the locations indicated on Parts 17b and 16 as well as the aligned clearance holes in 17a and 16. Note: do not secure the bottom holes yet; those will be used to secure the upper assembly with the lower assembly.

Step 15) Align parts 17c, 17d and 18 with the assembly in Step 16 and secure at the aligned through holes except for the bottom two holes.

Solar Dryer Assembly Guide: Step 16) Align the assembly from Step 15 with the solar dryer as shown below.

Step 17) Secure the parts in Step 16 together at the locations indicated (repeat at identical locations on 17a, 17b, 17c and 17d). Note: some bolts may need to be unscrewed and rescrewed in order to secure the parts.

Step 18) Secure Part 19 (the 15 shelf pieces) as shown below. There are three screw locations for each shelf. Some screws may have to be unscrewed and reattached where the upper cabinet connects with the lower cabinet and solar collectors.

Roof Assembly Guide: Step 19) Secure Parts 20, 21 and 22 together as shown. Note the switching of Parts 21 and 22 on the two different sides of the roof.

Step 20) Secure two Part 23s to the assembly from the previous step as shown. This is for the solar fan. Between the two Part 23s, sandwich the solar fan. Part 23 goes on top of Parts 21 and 22.

Step 21) IF USING THE WIND TURBINE: Similar to the attachment method in the step above, use two Part 24a’s to sandwich and trap the wind turbine and secure it to the roof.

IF USING THE CHIMNEY: Use only one Part 24b and secure it to the assembly in Step 20. Weld the chimney to Part 24b (where the opening is and stick the chimney about 2-3 inches below the surface of Part 24b) once it is assembled after the next step.

Chimney Assembly Guide: Step 22) To assemble the chimney, take Part 25 and cut slits on the top of the cylindrical tube such that they can be folded at an angle to support the chimney cap. (Part 26) Weld the chimney cap into place or use another simple mechanical attachment method. Solar Dryer Assembly Guide: Step 23) Align the roof assembly with the solar dryer assembly as shown below. The solar fan should face the same direction as solar collector 2.

Step 24) Attach the roof assembly and the solar dryer at the locations indicated (repeat on the opposite side).

Step 25) Attach the lower cabinet door to the solar dryer with the hinges.

Step 26) Secure Parts 27 and 28 to the upper cabinet and secure the upper cabinet door (Part 29) as shown below.

Step 27) Secure magnetic tape along Parts 28, 14 and the faces of Parts 3a, 15d and 17d that the doors of the cabinets overlap on.