P15484 Solar Assisted Essential Oil Distiller System Level Design - - PDF document

P15484 – Solar Assisted Essential Oil Distiller System Level Design Pre-Read

October 2, 2014 Manual Solar Tracking Concept Elimination

Figure 1: Oil Yield Requirements to Break Even

Industry standard oil yields range from 0.3%-2%. If solar tracking system were performed manually the distiller would have to produce oil at a yield rate much higher than industry standard. Heat Source Concept Analysis The team collected all criteria the customer might be interested in:

• 1. % of solar/renewable energy

The sun was assumed to be sufficiently intense 6 hours per day. For the 48 hour cycle this means 25% of the cycle has intense sunlight, 50% for the 2, 12 hour session cycle.

• 2. Initial cost

Benchmarked products were used to estimate the heating sub-system cost. A cost per Watt was calculated so that the cost could be scaled to the necessary Wattage. For some concepts, a best fit line on benchmarked products was used to determine this cost per Watt. Example:

Process Time (Days) % of Energy From Propane Yield Necessary to Break Even (no Human Powered Tracking) Yield Necessary to Break Even (Human Powered Tracking Tracking) 4 5% 1.0% 5.3% 4 10% 1.1% 5.4% 4 15% 1.2% 5.5% 4 20% 1.3% 5.6% 4 25% 1.4% 5.7% 3 30% 1.3% 4.5% 3 35% 1.4% 4.6% 3 40% 1.5% 4.7% 3 45% 1.6% 4.8% 3 50% 1.7% 4.9% 2 55% 1.6% 3.8% 2 60% 1.7% 3.9% 2 65% 1.8% 4.0% 2 70% 1.9% 4.1% 2 75% 2.0% 4.2% 1 80% 1.9% 3.0% 1 85% 2.0% 3.1% 1 90% 2.1% 3.2% 1 95% 2.2% 3.3% 1 100% 2.3% 3.4%

y = 3.2374x R² = 0.7967 500 1000 1500 2000 100 200 300 400 Cost ($) Energy (W)

Cost Vs Energy Produced (Evacuated Tubes)

• 3. Operating cost
• a. Gas (propane) required

All energy required to boil water that is not supplied by the sun will be supplied by propane.

• b. Labor cost

Labor was based off a rate of $6 per 8 hour day. Concepts requiring propane were assumed to require 10 minutes of labor while concepts requiring manual tracking were assumed to require 1 hour of labor per cycle (see known values and assumptions).

• 4. Hypothetical payback period

It is expected that a working system will be purchased by grants and thus will not need to be paid

• back. However, the payback period provides a basis for comparison between concepts.
• 5. Annual savings vs just propane

The cost to operate the concept was subtracted from the cost of running the system on only propane, which acts as a datum for this analysis. No quantitative priority was given to any of the criteria.

1, 48 hour session – 25% intense sunlight – 111W Required

Photovoltaic Evac Tube Parabolic Reflector Parabolic Reflector w/ Tracker Flat Plate Solar Trough Solar Trough w/ Tracker Water Lens Fresnel Lens Fresnel Lens w/ Tracker Propane Percent renewable* 100% 25% 25% 25% 25% 25% 15% 25% 25% 25% 25% 25% 0% Percent from propane* 0% 75% 75% 75% 75% 75% 85% 75% 75% 75% 75% 75% 100% Initital cost (not including propane components) $1,200 $359 $227 $99 $80 $300 $228 $132 $332 $265 $211 $290 $ - Gallons of propane/cycle 0.000 0.163 0.163 0.163 0.163 0.163 0.185 0.163 0.163 0.163 0.163 0.163 0.217 Labor hours required/cycle 0.167 1.167 0.167 1.167 0.167 0.167 1.167 0.167 2.167 1.167 0.167 Payback period (yrs) 6.49 11.61 NEVER 3.20 NEVER 9.70 18.08 NEVER 10.74 NEVER NEVER 9.38 0.00 Payback period (yrs, assuming gas is free) 6.49 2.13 3.28 0.59 1.15 1.78 1.35 1.91 1.97 NEVER 3.05 1.72 0.00 Annual savings vs propane $183.12 $29.25 $(69.75) $29.25 $(69.75) $29.25 $10.94 $(69.75) $29.25 $(168.75) $(69.75) $29.25 $(0.00)

2, 12 hour sessions – 50% intense sunlight – 222W Required

Photovoltaic Evac Tube Parabolic Reflector Parabolic Reflector w/ Tracker Flat Plate Solar Trough Solar Trough w/ Tracker Water Lens Fresnel Lens Fresnel Lens w/ Tracker Propane Percent renewable* 100% 50% 25% 50% 50% 50% 15% 50% 50% 50% 50% 50% 0% Percent from propane* 0% 50% 75% 50% 50% 50% 85% 50% 50% 50% 50% 50% 100% Initital cost (not including propane components) $1,500 $647 $517 $395 $ 80 $300 $910 $132 $332 $270 $237 $316 $ - Gallons of propane/cycle 0.000 0.109 0.163 0.109 0.109 0.109 0.185 0.109 0.109 0.109 0.109 0.109 0.217 Labor hours required/cycle 0.167 1.167 0.167 1.167 0.167 0.167 1.167 1.167 2.167 1.167 0.167 Payback period (yrs) 8.12 8.43 NEVER 5.15 NEVER 3.91 72.15 NEVER NEVER NEVER NEVER 4.12 0.00 Payback period (yrs, assuming gas is free) 8.12 3.85 7.46 2.35 1.15 1.78 5.41 1.91 4.79 NEVER 3.42 1.88 0.00 Annual savings vs propane $183.12 $75.03 $(69.75) $75.03 $(23.97) $75.03 $10.94 $(23.97) $ (23.97) $(122.97) $(23.97) $75.03 $(0.00) Known values & assumptions Comments / notes Total Energy Req (MJ): 19.3 Propane Cost per Gallon: $6.38 $25/tank at approx 4.7 gal/tank Distillation cycles per year: 132 4 months of prime season, 120 days, 60 distillations + 60% in the slower season, 8 months, 72 distillations Labor rate in Haiti ($/hour): $0.75 Assume $6 / day Oil yield: 2% Oil yield per cycle ($): $1.40 Processing 1 lb of plant material at 1% yield, vetiver oil sale price = $70/lb -> $0.70 per cycle Energy per gallon of propane (MJ): 88.80 http://www.extension.iastate.edu/agdm/wholefarm/html/c6-87.html 100% propane annual cost ($): 183.12 19.3MJ per cycle / 88.8MJ/gal = 0.217gal per cycle .217gal/cycle x $6.38/gal x 132 cycles = $183.04 Labor hours for tracking + propane: 1.17 5 minutes to adjust tracking each half hour for 6 hours per day + 5 minutes to turn propane on&off 2 times = 70 minutes Labor hours for just propane: 0.17 5 minutes to turn propane on&off 2 times = 10 minutes Initial cost of propane: $90.00 $30 tank + $60 burner & hose

Morphological Analysis Table System Level Alternatives

Functions 1 2 3 4 5 6 7 8 9 10 11

Convert Energy Boil Water Condense Water Direct Steam Through Plant Material Separate Oil Insulate

Spray Foam Foam Pipe Wrap Fiberglass Insulation Tape Insulation Sheet Insulation Contain entire system

Convert Energy Boil H2O Condenser Direct Steam Separate Oil Insulate Picked This Combination for: A Reflector + Methane Pressure cooker Coil bath Dry steam, one tube Separatory funnel Spray foam Best Options B Evacuated tube Pressure cooker Cool coil Wet-dry steam Floatation separator Pipe foam Next Best Options C Photo voltaic battery Heat exchane boiler Air cooled tube Fan directed steam Centrifuge None Worst D Methane burner Pot Flat top Wet-dry steam Turkey baster None Cheapest E Lens Gold nano-particles Cool coil dry steam Floatation separator Spray foam Most Expensive F Methane Pressure cooker Air cooled Wet-dry steam Separatory funnel Spray foam General Option G Flat plate Pressure cooker Cone and bowl 2 layered Height drain Foam tape General Option H Evac Tube + Methane Pot Flat top Wet-dry steam Turkey baster None Option D + Evacuated tube (Post 1st Pugh run through) I Propane / Electricity Chamber / pot air cooled Wet-dry steam Separatory funnel None Homebrewer Ben Reflector + Methane Pressure cooker w/drip feed Aircooled Dry steam Separatory funnel Spray foam Ben's option Peter Evac Tube + Methane Pot w/ drip feed Coil bath Dry steam Separatory funnel Spray foam Peter's pick John Reflector + Methane Pressure cooker Water cooled cone Wet-dry steam Separatory funnel Spray foam John's pick Nate Flat plate + Methane Pressure cooker Coil bath Wet-dry steam Separatory funnel Spray foam Nate's pick Bruno Reflector + Methane Pressure + pot Coil bath Wet-dry steam Seperatory funnel Spray foam Bruno's pick Alternatives