Energy and Water Use in Arizona Agriculture

Thomas L. Acker, Chelsea Atwater Edana French, Mark Glauth,

And Dean Howard Smith

Why This Study?

• Increasing energy and water concerns in Arizona are the driving forces to improve the efficiency of agricultural production within the state.

• The analysis is “from seed to the edge of the field.”

The Goal Of The Research Project

• Identify and quantify all water and direct fossil fuel-based energy uses from – The production of the initial seed, – Through the treatments of the soil– Various chemical introductions, – All the way until the crop is harvested and loaded

for transportation.

Importance to Arizona Farming

• Real energy costs have been increasing in recent years and are likely to continue to do so in the foreseeable future.

• The extended draught combined with unprecedented population growth in Arizona is causing increasing concerns about water management.

Existing Ag Sector

• Approximately 900,000 acres • A variety of fruits, vegetables, grains, hay and

cotton• Approximately 4.9 million acre feet of water • Energy used has an approximate high range of

3.6x1013 BTU or roughly 1,204 MW.

How Much Energy is That?

• Equivalent of about 2 Cholla Power plants operating at full capacity for one year.

• Alternatively this is the energy in 290,000,000 gallons of gasoline

• Around 38,652 tanker trucks of gasoline.• Produces 536,000 TONS of CO2

The Process

• List the various operations• Machine hours per operation• Number of operations

– Some are shared so not all integers• Diesel consumption per hour

– Varies as different machines are used– No hand or contract operations

• Diesel/acre = Machine hours/acre*Times*Diesel/hours.

Cabbage as an Exemplar

Land Preparation and Growing Operations Month Operation Machine Hours Times Diesel/hr Diesel/acreAug Rip 0.225 0.5 16.13 1.81Aug Plow 0.45 1.0 18.33 8.25Aug Disk 0.225 3.0 19.35 13.06Aug Laser Level 0.45 0.5 15.62 3.52Sep Soil fertility 0 1.0 0 0.00Sep Herbicide (ground) 0.225 1.0 5.75 1.29Sep List 0.225 1.0 11.39 2.56Sep Plant 0.6 1.0 12.31 7.39Sep Insecticide (ground) 0.150 1.0 7.61 1.14Sep Buck Rows 0.05 5.0 5.36 1.21Sep Irrigate 0.000 7.0 0 0.00Sep Disk Ends 0.045 5.0 7.61 1.71Sep Insecticide (ground) 0.150 1.0 7.28 1.09Sep Thinning 0.000 1.0 0 0.00Sep Cultivate/side dress 0.180 2.0 15.30 5.51Sep Fertilizer (ground) 0.450 2.0 10.52 9.47Sep Hand Weeding 0.000 2.0 0 0.00Sep Insecticide (ground) 0.225 1.0 6.49 1.46Sep Cultivate 0.563 2.0 7.64 8.60Oct Fertilizer (ground) 0.450 2.0 5.75 5.18Nov Insecticide (ground) 0.225 1.0 6.49 1.46Dec Harvest/field pack 0.000 1.0 0 0.00Dec Haul, custom 0.000 1.0 0 0.00Dec Disk Residue 0.225 1.0 19.35 4.35Operations total diesel/acre 79.06

Irrigation

• Between 25 acre inches or 2.08 acre feet and 42 acre inches or 3.5 acre feet.

• 123.01 BTU/cubic foot of water• 139,000 BTU/gallon diesel

Irrigation high range 18,753,800 btu/acre 134.92 gal/acre

low range 11,162,976 btu/acre 80.31 gal/acre

Chemicals• Estimates for the amount of each

chemical types and the amount of coverage were determined.– Varies by crop

• Since the former study used pounds per acre and the latter study used MJ/kg, a series of conversions were necessary to determine the energy used per acre.

High

  total acres   Energy Use per kg

  3400 Pounds/acre MJ/kg BTU/acre

Fertilizer % Coverage  Nitrogen 0.96 182 75.63 5.92E+06

Phosphorus 0.77 178 15.8 1.21E+06

Pesticide 0.85 7.42 326.34 1.04E+06

Herbicide 0.57 4.82 252.36 5.23E+05

Other Chemicals 0.58 2.54 252.36 2.76E+05

Total       8.98E+06

Low

  total acres    Energy Use per kg  3400 Pounds/acre MJ/kg BTU/acre

Fertilizer % Coverage

Nitrogen 0.96 148 75.63 4.82E+06

Phosphorus 0.77 107 15.8 7.28E+05

Pesticide 0.85 1.48 326.34 2.08E+05

Herbicide 0.57 1.58 252.36 1.71E+05

Other Chemicals 0.58 0.00 252.36 0

Total       5.92E+06

Eat Your Cabbage

• Sturdy, abundant and inexpensive, cabbage is a longstanding dietary staple throughout the world and is so widely cultivated and stores so well that it is available throughout the year.

Converting into diesel equivalents the high and low range for the embodied fossil fuels in the various chemicals is shown in Table 4.

Chemicals

high range 8,975,576 btu/acre 64.57 gal/acre

low range 5,924,090 btu/acre 42.62 gal/acre

Seeds

• A high estimate for the required seeds per acre is 156,000 (Cabbage Production in California) and a low value from the Arizona crop budget is 90,000.

• An average embodied energy value is 20.64 MJ/kg of seeds.

• An estimate for the amount of cabbage seeds per pound is 126,000.

• A Units Nightmare!

Seedshigh range 10,986 btu/acre 0.08 gal/acre

low range 6,338 btu/acre 0.05 gal/acre

Total Operations for CabbageOperationsacres 3,400total diesel 268,807head/acre 10,647diesel/head 0.00743btu/head 1,032Kcal/head 4,096

• 139,000 btu/gallon• 3.97 Kcal/btu

Seafood Cabbage Pancakes

2 cups of all-purpose flour 1 teaspoon of baking powder 1 teaspoon of salt 1 cup of vegetable broth or Dashi 2 cups of shredded white cabbage 1 Egg 2 cups of Master Seafood Mixture Salt, to taste Freshly-ground white pepper Canola oil,  for cooking 1/4 cup of Oyster sauce 1/2 cup of Bonito Flakes, for garnish

Energy Needed to Produce Cabbage

Total Diesel Highacres 3,400total diesel 791,537head/acre 10,647diesel/head 0.02187btu/head 3,039Kcal/head 12,061

Total Diesel Lowacres 3,400total diesel 594,174head/acre 10,647diesel/head 0.01641btu/head 2,282Kcal/head 9,054

Cabbage CassaroleEach Servings: 1/2 cupExchanges 1 Vegetable 1/2 meat Chol 67 mg Calories 58 Carbo 5 gm Protein 5 gm Fat 2 gm Fiber Tr. Sodium 342 mg

A Simple Energy Budget• The estimated amount of embodied fossil fuel in each head of

cabbage grown in Arizona is between 9,054 and 12,061 kilocalories.

• A meaningful comparison for these values is the USDA standard of 2,000 Kcal of food per person per day!

• As such the amount of energy needed to keep the typical American going for 6 days as food intake is the same as the energy necessary to produce a single head of cabbage

Water Use

"How I Lost 55 Pounds" Amazing Chinese Weight Loss Secret. As Seen On CNN, NBC, CBS & Fox News

Water UseAcres 3,400feet high 3.50feet Low 2.08Gallons/acre High 1,140,480Gallons/acre Low 678,857Total Gallons High 3,877,631,898Total Gallons Low 2,308,114,225Head/acre 10,647Water/head High 107 gallonsWater/head Low 64 gallons

Other Crops

OperationsCrop acres diesel/acre head/acre diesel/head btu/head Kcal/headBroccoli 9,900 142 9,728 0.0146 2,031 8,059Cabbage 3,400 79 10,647 0.0074 1,032 4,096Cantalopes 17,700 76 12,165 0.0000 866 3,438Cauliflower 4,600 98 11,460 0.0085 1,183 4,694Chiles Peppers 6,800 50 11,460 0.0044 611 2,423Dry Onions 1,600 72 36,000 0.0020 279 1,107Head Lettuce 900 131 27,888 0.0047 654 2,596Honeydews 2,500 72 6,488 0.0112 1,551 6,155Leaf Lettuce 7,100 131 27,888 0.0047 654 2,596Potato 6,200 227 29,200 0.0078 1,080 4,288Romaine 17,300 122 27,888 0.0044 611 2,423Spinach 6,000 60 27,888 0.0021 298 1,184Watermelons 6,400 150 44,000 0.0034 475 1,886

Operations Only• Broccoli 8,059 Kcal/head• Honeydew 6,155

Kcal/melon• Remember a calorie is

the amount of energy needed to heat 1 gram of water.

• You weigh a lot more than 1 gram, so we measure food in Kilocalories or Kcal.

High Estimates for DieselTotal Diesel High

Crop acres total diesel head/acre diesel/head btu/head Kcal/headBroccoli 9,900 2,823,894 9,728 0.0293 4,076 16,173Cabbage 3,400 791,537 10,647 0.0219 3,039 12,061Cantaloupes 17,700 4,336,552 12,165 0.0201 2,799 11,109Cauliflower 4,600 1,129,660 11,460 0.0214 2,979 11,820Chiles Peppers 5,400 954,899 6,800 0.0260 3,615 14,344Dry Onions 1,600 388,114 36,000 0.0067 937 3,717Head Lettuce 900 358,438 27,888 0.0143 1,985 7,877Honeydews 2,500 491,586 6,488 0.0303 4,213 16,717Leaf Lettuce 7,100 2,827,674 27,888 0.0143 1,985 7,877Potato 6,200 2,978,368 29,200 0.0165 2,287 9,074Romaine 17,300 5,897,631 27,888 0.0122 1,699 6,743Spinach 6,000 1,017,796 27,888 0.0061 845 3,355Watermelons 6,400 1,960,460 44,000 0.0070 968 3,840

Low Estimates for DieselTotal Diesel Low

Crop acres total diesel head/acre diesel/head btu/head Kcal/headBroccoli 9,900 2,582,073 9,728 0.0268 3,727 14,788Cabbage 3,400 594,174 10,647 0.0164 2,282 9,054Cantaloupes 17,700 3,603,554 12,165 0.0167 2,326 9,231Cauliflower 4,600 1,012,567 11,460 0.0192 2,670 10,595Chiles Peppers 5,400 585,251 6,800 0.0159 2,215 8,791Dry Onions 1,600 301,605 36,000 0.0052 728 2,888Head Lettuce 900 293,422 27,888 0.0117 1,625 6,448Honeydews 2,500 397,349 6,488 0.0245 3,405 13,513Leaf Lettuce 7,100 2,314,773 27,888 0.0117 1,625 6,448Potato 6,200 2,304,763 29,200 0.0127 1,770 7,022Romaine 17,300 5,500,610 27,888 0.0114 1,585 6,289Spinach 6,000 748,221 27,888 0.0045 622 2,466Watermelons 6,400 1,583,453 44,000 0.0056 782 3,102

Total Diesel Consumption

• You are what you eat.• You are Oil!• Honeydew 15,000 -

20,400 Kcal per melon• Leaf Lettuce Garnish

7-9,000 Kcal/head

Water Use Per UnitWater Use

CropAcre feet

high/acAcre feet

Low/acTotal Gallons

HighTotal Gallons

LowWater/head

HighWater/head

Low

Broccoli 2.83 1.88 9.1.E+09 6.0.E+09 95 63

Cabbage 3.50 2.08 3.9.E+09 2.3.E+09 107 64

Cantaloupes 3.33 1.67 1.9.E+10 9.6.E+09 89 45

Cauliflower 3.08 2.08 4.6.E+09 3.1.E+09 88 59

Chiles Peppers 4.50 1.82 1.0.E+10 4.0.E+09 128 52

Dry Onions 2.75 1.94 1.4.E+09 1.0.E+09 25 18

Head Lettuce 4.29 3.42 1.3.E+09 1.0.E+09 50 40

Honeydews 3.33 1.86 2.7.E+09 1.5.E+09 167 93

Leaf Lettuce 4.29 3.42 9.9.E+09 7.9.E+09 50 40

Potato 5.00 2.03 1.0.E+10 4.1.E+09 56 23

Romaine 4.29 3.42 2.4.E+10 1.9.E+10 50 40

Spinach 3.00 1.25 5.9.E+09 2.4.E+09 35 15

Watermelons 4.17 1.86 8.7.E+09 3.9.E+09 31 14

Water Use Totals

CropTotal acre feet

highTotal acre feet

low

Broccoli 28,050 18,563

Cabbage 11,900 7,083

Cantaloupes 59,000 29,500

Cauliflower 14,183 9,583

Chiles Peppers 30,600 12,365

Dry Onions 4,400 3,107

Head Lettuce 3,863 3,075

Honeydews 8,333 4,638

Leaf Lettuce 30,471 24,258

Potato 31,000 12,555

Romaine 74,246 59,108

Spinach 18,000 7,500

Watermelons 26,667 11,872

Total 340,713 203,207

Variations in EstimatesVariations

Crop Diesel Water

Broccoli 1.13 1.51

Cabbage 1.38 1.68

Cantalopes 1.28 2.00

Cauliflower 1.16 1.48

Chiles Peppers 1.78 2.47

Dry Onions 1.30 1.42

Head Lettuce 1.23 1.26

Honeydews 1.31 1.80

Leaf Lettuce 1.23 1.26

Potato 1.37 2.47

Romaine 1.09 1.26

Spinach 1.48 2.40

Watermelons 1.33 2.25

Water Use

• High values are more likely correct for arid Arizona.

• 1 bunch spinach avg. = 25 gallons• 400 glasses of water

Servings

CropSize

ounces Kcal refuseunit weightpounds

Broccoli 3.2 31 0.39 0.52

Cabbage 3.1 21 0.2 2.89

Cantaloupes 1.9 19 0.49 3.78

Cauliflower 3.5 25 0.61 2.27

Chiles Peppers 2.6 30 0.27 0.41

Dry Onions 3 36 0.1 0.55

Head Lettuce 1.9 8 0.05 1.64

Honeydews 4.4 45 0.54 3.27

Leaf Lettuce 1.9 8 0.05 1.04

Potato 2.6 58 0 0.85

Romaine 1.7 8 0.06 1.66

Spinach 1.1 7 0.28 0.80

Watermelons 4.3 37 0.48 15.76

Calculations

• Average weight= total weight/sample size• Weight/unit = average weight*16• Useable/unit=weight/unit *(1- refuse%)• Serving/unit= (useable/unit)/ serving size

A Day Shopping 9/29/07Crop

sample size

sample ounces useable serve/unit

Broccoli 31 8.4 5.1 1.6

Cabbage 25 46.2 36.9 11.9

Cantaloupes 31 60.4 30.8 16.2

Cauliflower 22 36.4 14.2 4.1

Chiles Peppers 31 6.6 4.8 1.8

Dry Onions 37 8.8 8.0 2.7

Head Lettuce 31 26.2 24.9 13.1

Honeydews 8 52.3 24.0 5.5

Leaf Lettuce 20 16.7 15.9 8.4

Potato 31 13.6 13.6 5.2

Romaine 25 26.5 24.9 14.6

Spinach 13 12.8 9.2 8.4

Watermelons/pound 10 16.0 8.3 1.9

Energy Used in Production

CropKcal/serve

operationsKcal/serve

highKcal/serve

lowKcal/serve

avg

Broccoli 5041 11432 10120 10776

Cabbage 344 1212 879 1045

Cantaloupes 212 807 632 719

Cauliflower 1158 3397 2939 3168

Chiles Peppers 1312 6141 3444 4792

Dry Onions 417 1610 1236 1423

Head Lettuce 198 685 559 622

Honeydews 1127 3740 2852 3296

Leaf Lettuce 311 1076 878 977

Potato 819 1969 1437 1703

Romaine 165 536 490 513

Spinach 142 494 334 414

Watermelons 975 2338 1760 2049

Water Used in Production

Cropwater/serve

highwater/serve

lowwater/serve

avg

Broccoli 59.4 39.3 49.3

Cabbage 9.0 5.4 7.2

Cantaloupes 5.5 2.8 4.1

Cauliflower 21.6 14.6 18.1

Chiles Peppers 69.3 28.0 48.6

Dry Onions 9.4 6.6 8.0

Head Lettuce 3.8 3.0 3.4

Honeydews 30.6 17.1 23.9

Leaf Lettuce 6.0 4.8 5.4

Potato 10.7 4.3 7.5

Romaine 3.4 2.7 3.1

Spinach 4.2 1.7 3.0

Watermelons 15.9 7.1 11.5

Efficiency

• Kcal of production energy/Kcal of food energy

• Gallons of water/Kcal of food energy

• 8 ounce glasses

Cropenergy efficiency

water efficiency

glasses of water

Broccoli 347.6 1.591 25.5

Cabbage 49.8 0.342 5.5

Cantaloupes 37.9 0.217 3.5

Cauliflower 126.7 0.725 11.6

Chiles Peppers 159.7 1.621 25.9

Dry Onions 39.5 0.222 3.6

Head Lettuce 77.8 0.429 6.9

Honeydews 73.2 0.530 8.5

Leaf Lettuce 122.2 0.674 10.8

Potato 29.4 0.129 2.1

Romaine 64.1 0.384 6.2

Spinach 59.2 0.424 6.8

Watermelons 55.4 0.311 5.0

Maybe President Bush Was Correct!

• No Broccoli• 350 Kcal for each Kcal of food energy• 25 glasses of water for each Kcal of food• Next Project: Nutritional efficiency

Nutrient Amount DV(%) NutrientDensity

World's HealthiestFoods Rating

vitamin C 123.40 mg 205.7 84.8 excellentvitamin K 155.20 mcg 194.0 79.9 excellentvitamin A 2280.72 IU 45.6 18.8 excellentfolate 93.91 mcg 23.5 9.7 excellentdietary fiber 4.68 g 18.7 7.7 excellentmanganese 0.34 mg 17.0 7.0 very goodtryptophan 0.05 g 15.6 6.4 very goodpotassium 505.44 mg 14.4 6.0 very good

“From Seed To Edge Of The Field.”

• Does not include – Human labor– Washing– Refrigerating– Packaging– Transporting– Storing– Cooking

We value the world in which we work and live. We support our local schools, and donate generously to a number of charitable organizations in our community and throughout our industry.We respect and value the environment in which we grow our products. All of our fresh vegetable products are natural, containing no genetically modified organisms.

Making Agriculture BetterFarmers are people