Feasibility of Bio-Gasification Technology for Rural Off-Grid - - PowerPoint PPT Presentation

Feasibility of Bio-Gasification Technology for Rural Off-Grid Electrification in Namibia

Palyomwene Mutilifa (NUST)

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Background

• Bush Encroachment!
• Biomass Gasification is a thermochemical conversion process through which

combustible material such as biomass, is subjected to partial combustion in the presence of limited supply of air

• The combustible gas is composed primarily of carbon monoxide (CO), Hydrogen

(H2) and methane (CH4) as fuels.

• Ancient Technology:
• Street lights in the 1800s
• 900 000 Cars ran on 1900s

BOTH FROM WOOD GAS

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Background

Gasifier Unit Conversion Unit Cleaning and Cooling unit

Wood

Charcoal

Biomass Gasification CAN provides clean alternative source of base load electricity

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76%

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Existing Gasification Plant In Namibia

Name Location Manufacturer Type of Gasifier Biomass Rated Output Status

CBEND Farm Pierre, Outjo Ankur Scientific Energy Technologies Pty. Ltd Downdraft fixed bed Woodchip / woodblock 250 kW Shut down Makarra Briquette Otjiwarongo Local Updraft fixed bed Charcoal 42.4 kW Shut down Makarra Charcoal Otjiwarongo Local Downdraft fixed bed Charcoal 44 kW Running NUST Trailer NUST, Windhoek Carbo Consult & Engineering (Pty) Ltd Updraft fixed bed Wood / Charcoal 15 kW Running

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Existing Gasification Plant In Namibia: CBEND

• Project costed N$14 000 000.00
• 1.0-1.1 N$/kW Levellised cost
• Created 30 Jobs

Challenges Recommendations Wood Preparation Equipment Reliable and efficient wood preparation methods Heat loss not stored as source of Thermal Energy Heat loss should be captured for energy application Usage of Refrigeration system(15 kw) The electricity generated should be in directly fed to off-grid communities rather than the national grid. Only 50kW/250kW was registered

• Gasification system on such a large scale are simply not feasible for

rural Namibia (Andrew, Richard, Robert, & Wang, 2011).

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Existing Gasification Plant In Namibia: Makarra Briquette

No. Parameter Unity Value 1 Operational Hours h 23 2 Operational days day 6 3 Capital cost (Technology & Installation) N$ 25 000.00 4 Biomass Cost N$/t 1500.00 5 Required Biomass t/yr. 45 8 Diesel cost saved N$/yr. 811 200.00 9 Total fuel cost N$/yr. 448 350.00 10 Producer Gas: Diesel Ratio

• 77:23

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• Approx. Biomass Collection Radius

Km 0.5

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Peak Load Kw 20

• Problems: Lack of technical knowledge, maintenance, Instrumentations, Mismanagement of tar, ash
• The plant was expanded in April 2019 & is now powered by CENORED and planning to switch to

solar power by 2020.

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Existing Gasification Plant In Namibia: Makarra Charcoal

No. Parameter Unity Value 1 Operational Hours h 8 2 Operational days day 5 3 Capital cost (Technology & Installation) N$ 45 000.00 4 Biomass Cost N$/t 1500.00 5 Required Biomass t/yr. 4 10 Producer Gas: Diesel Ratio

• 25:85

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• Approx. Biomass Collection Radius

Km 0.05

• Lack of constant monitoring at the

grate, Frequent shaking

• Poor gas filtering system :

Mattress Foam

• Lack of Instrumentation

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Existing Gasification Plant In Namibia: NUST TRAILER

• ¼ systems to run on Petrol
• On average, petrol engine running on

combustible gas produces 0.55-0.75 kWh

• f energy from 1kg of biomass

(Rajvanshi, 1986).

• Excellent gas clean-up systems (Cyclone,

wet charcoal & wood shaving).

• Still being renovated for experimental

purposes

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Feasibility for Rural Off-grid Electrification

Barriers Feedstock quality and availability Constraint Technology Limitation Lack of Viable Business Model Limited Operator technical capacity Poor access to manufacturer support and spare parts

"The barriers facing gasification are meanwhile too significant and wide-ranging for research to make a significant difference to uptake. Gasification-related research is therefore not deemed worth supporting“ (LTS, 2017)

Disagree!

Abundant Biomass Training Local Manufacturers

• Feedstock ash Content
• Different Feedstocks

Kernel shell exudes acidic oil

• Lack of instrumentations
• International manufacturer
• Installing Capacity>100 kW
• Fulfils HPP-to increase the

provision of rural electrification by 50%.

• Gasification Awareness

Feasible In Namibia Fuel Wood works well with gasifiers (Dimpl,2011)

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Feasibility for Rural Off-grid Electrification

Plant Maintenance Once a week 312 days/yr. Instrumentation Downdraft gasifier 70% Syngas Engine deration 30%

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Feasibility for Rural Off-grid Electrification: Woodfeedstock

1000 2000 3000 4000 5000 5kw 30kw 100kw

N$1000

Net Present Value

• 1000000
• 500000

500000 1000000 1500000 2000000 2500000 3000000 1.00 2.00 3.00 4.00 5.00 6.00 7.00 8.00 9.00 10.00

N$ Years

Cash Flow

5 kw 10 kw 30 kw 50 kw 100 kw

0.00 5.00 10.00 15.00 20.00 1 IRR (%)

Internal Rate of Return (%)

100kw 50kw 30kw 10kw 5kw

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0.0 2.0 4.0 6.0 8.0 10.0 12.0 14.0 16.0 18.0 5kw 30kw 100kw

N$/kWh

Production Cost

Diesel Generator Production Cost 200 400 600 800 1000

5KW 10KW 30KW 50KW 100KW

COST (N$1000 )

INVESTMENT COSTS

3 5 16 26 52 10 20 30 40 50 60 1

Total Number of Household Supplied

100 kw 50 kw 40 kw 10 kw 5 kw

Feasibility for Rural Off-grid Electrification: Woodfeedstock

500 1000 500000 1000000 1500000 5kw 10kw 30kw 50kw 100kw

(t/y) (t)

Feedstock Consumption per Plant

Biomass consumption (t/year) <10% of Biomass Available

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2000 4000 6000 8000 10000 12000 14000 5kw 10kw 30kw 50kw 100kw

N$1000

Net Present Value

Wood Charcoal 0.0 10.0 20.0 30.0 40.0 50.0 60.0 5kw 10kw 30kw 50kw 100kw

Internal Rate of Return

Wood Charcoal 100 200 300 400 500 600 700 800 900 1000

N$1000

Investment Cost

Wood Charcoal

Feasibility for Rural Off-grid Electrification: Charcoal Vs. Wood

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Feasibility for Rural Off-grid Electrification: Charcoal Vs. Wood

5 10 15 20 25 30 35 40 45 50 5kw 10kw 30kw 50kw 100kw

N$/kWh

Production Cost

Wood Charcoal 10 20 30 40 50 60 5kw 10kw 30kw 50kw 100kw

• No. of Households

Total Number of Household Supplied

Charcoal Wood

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Feasibility for Rural Off-grid Electrification

Marula Kernel

• Drought-resistant tree that is widely

distributed in sub-Saharan tropical Africa.

• Mostly found in the northern part of

Namibia.

• Dry kernels are used as source of fire as

well as fertilizer.

• 80 000 households, 5 estimated Trees.

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1km Distance

5kw 10kw 30kw 50kw 100kw Production Cost (N$/kwh) 15.82 8.27 4.53 3.77 3.02 Investment Costs (N$1000) 45.98 84.28 262.17 433.29 862.08 Net Present Value (N$1000) 1309.4 1341.64 2007.22 2678.23 4076.81 Internal rate of Return(%) 17.16 9.72 4.79 3.91 3.05 Biomass consumption (t/year) 39.04 78.07 234.22 390.36 780.72 Biomass Available (t) 15.00 45.00 195.00 300.00 600.00 No Of Households 1 3 13 20 40

• Distribution Cost
• Transportation Cost

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Feasible for Small scale <10kW Feasibility for Rural Off-grid Electrification

Feasibility for Rural Off-grid Electrification

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• For as long us the plant is maintained, monitored &

understood locally, small scale plant will always be feasible.

• ELECTRICITY IS THE PASSWORD!
• Establishment
• f

Policies to effortlessly influence the integration

• f

biomass gasification with

• ther

existing renewable technology.

Feasibility of Bio-Gasification Technology for Rural Off-Grid Electrification in Namibia

Thank You!