Economics of Using Desalination Plants in Agriculture Seminar on - - PowerPoint PPT Presentation

Slim Zekri & Salem Al-Jabri Economics of Using Desalination Plants in Agriculture

Seminar on Small Desalination Units for Agriculture Sustainability: Challenges and Opportunities 5-6 March 2018 Al Nahda resort & Spa, Barka Sultanate of Oman

Desalination

• Only 2% of Desalinated water globally is used

for agricultural purposes

Main purpose of installation of desalination units

Farm Size in Feddans Main Purpose of Desalination < 5 5 to 10 > 10 Total Agriculture 14% 2% 6% 22% Domestic 14% 0% 6% 20% Domestic + Agriculture 38% 14% 6% 58% Total 66% 16% 18% 100%

Main Crops

1 2 3 4 5

Grass Mango Lemon Palm

Is desalinated water used for intensive agriculture??

Main Purpose of Desalination % of farms having GH Total #

• f GH Total area in m2

Agriculture 4% 16 4200 Domestic + Agric 16% 25 4650 Grand Total 20% 41 8850

0.5 1 1.5 2 2.5 3

Cucumber tomato lettuce Classic products

Cost of Desalination

1.32 0.55 0.46

0.00 0.20 0.40 0.60 0.80 1.00 1.20 1.40

Max Avg Min

$/m3

Average Annual expenses per farm estimated at OR 2,400 Average cropped area = 1.7 Feddan Assuming 7,800 m3/Feddan Assuming drip irrig. Eff @ 80% Cost per Feddan =OR 1,400

Cost distribution

16% 8% 77%

Cost of Energy O&M costs Capital Cost

Cost Comparison

0.65

0.55 0.03 0.13 0.00 0.10 0.20 0.30 0.40 0.50 0.60 0.70

Average cost without electricity subsidy Average cost with electricity subsidy From wells Aflaj water price

$/m3

Average volume desalinated per year is 13,000 m3 Max = 41,500 m3 Min = 2,000 m3

International benchmarking

• In Spain irrigation water is mixed with 30%-40% of

desalinated water. Cost after mixing $0.39/m3

• 78% of farmers in Oman use pure desalinated

water for irrigation

0.65 0.29 0.63 0.40

0.00 0.10 0.20 0.30 0.40 0.50 0.60 0.70

Oman brackish GW Texas Brackish GW lowest Texas Brackish GW highest Spain Brackish groundwater

$/m3

Why Farmers can afford desalinated water in Spain

• Highly skilled full time small farmers
• Desalinated water is mixed with surface/GW
• Crop water requirement around 5,600 m3/ha
• High value crops: horticulture, Ornamental

plants, Fruit trees

• Strong cooperatives controlling part of the

marketing chain and getting a fair price for their products

• Large European market more than 400 million
• Added value 5.79 €/m3 - 1.08 €/m3 on average

Who are the Farmers using Desalination in Oman?

• Small hobby unskilled farmers
• Pure desalinated water is used by 78% at high cost
• Crop water requirement around 20,000 m3/ha
• Low value crops: dates, mango, Lemon
• Fragmented non-organized farmers
• Narrow market and difficult access to international

market due to pesticide residues and absence of cooperatives

• Cheap groundwater available for competing farmers

Conclusions

• Is desalination a priority?
• What if TWW is re-used for irrigation rather

than thrown to the sea?

• What if Centrally excess desalinated water is

used in Winter for agriculture?

Acknowledgement

• Thanks for the AFDF for funding this project