/5_Andaroodi

Standardization of civil engineering works of small hydropower plants (development of an optimisation tool) Settling basin Channel Forebay

Intake

Penstock

M. Andaroodi Lausanne 30.06.2005

ÉC OLE PO LY TEC H NIQU E FÉ DÉRALE D E LAUSAN NE

SECTIONS • Purpose • Scope of work • Intake • Settling basin • Next steps

ÉC OLE PO LY TEC H NIQU E FÉ DÉRALE D E LAUSAN NE

PURPOSE Purpose Scope of work Intake Settling basin Next steps

¾ Standardization of main structures of SHP as a function of design parameters (e.g. Q) with focus on high head power plants ¾ Development of typical design drawings for the main hydraulic structures ¾ Implementation of the standardized structures in a general applicable optimization tool for the layout of the hydropower plant

ÉC OLE PO LY TEC H NIQU E FÉ DÉRALE D E LAUSAN NE

SCOPE OF WORK Purpose Standardization of civil engineering works of small hydropower plants

Scope of work Intake Settling basin

Design criteria for the main components of SHP

Next steps

Intake

Settling basin

Canal

Forebay basin

Penstock

Standardization as a function of design parameters

Civil works: Standardization of geometry: Dimension of structures Construction details

Sample design drawings Concrete volume Formwork surface Reinforcement Estimation of excavation

Construction cost functions

ÉC OLE PO LY TEC H NIQU E FÉ DÉRALE D E LAUSAN NE

SCOPE OF WORK Purpose Scope of work Intake Settling basin Next steps

Existing optimization tool ''POPEHYE'' :

Implementation of standardized structures and costs in optimization strategies

Review and generalization Preparation of an english version

Derivation of general rules for optimization tools

Final results Design charts, tables and drawings Recommendations

Settling Basin Intake Canal

Forebay

Weir + Fishway

stoc Pen

Outl et C

han nel

k

Line Power

Table of Command Power House Residual Discharge Turbine & Generator

POPEHYE Main component of a small hydropower plant ÉC OLE PO LY TEC H NIQU E FÉ DÉRALE D E LAUSAN NE

INTAKE Purpose Scope of work Intake Settling basin Next steps

Purpose Divert water into a waterway leading to the power plant

Conventional type Bottom intake : It consists of a canal built in streambed and covered by a trashrack with a downward sloping profile.

Drop intake, Tyrolian type Sluiceway Intake

Trashrack

Tyrolian Intake

ÉC OLE PO LY TEC H NIQU E FÉ DÉRALE D E LAUSAN NE

INTAKE Purpose Scope of work Intake Settling basin Next steps

Design critera Tyrolian intake : Dimensions are based on the following formula: Qe =

2 ⋅c ⋅ μ⋅ B b ⋅ L ⋅ 2⋅g⋅h 3

b

Flow

écoulem ent fluvial

L : intake length over the grids (m) B : intake width (m) Q : design flow (m3/s) β : grid slope hcr : critical depth (m) h : water depth in start point of grid (m) μ : discharge coefficient (grill shape) c : grid coefficient (a/b, β)

6.00

L

hcr h

3.00

3.00

3.00

a

grille

grill

β

1.00

Qe μ = 0 62

Assumptions

1.00

Grid, a/b=0.5

0 65

1.0

2.0

Q=0.5 m3/s , a/b=0.5

a : 2 to 4 cm a/b : 1/3 , 1/2 , 2/3 β : 30 to 45o

1.9

S1

0.8

S2

S1 S2<S1

Recommendations: Extension of the calculated length by 20% for more security because of possible partial grid obstruction

1.65

9Intake position 9Stepped side walls ÉC OLE PO LY TEC H NIQU E FÉ DÉRALE D E LAUSAN NE

INTAKE Purpose Scope of work

Geometry of tyrolian intake

Intake Next steps

Width and Length of intake for different design discharges (0.25 to 3.0 m3/s).

a/b=0.5 , β=35o (grid slope: 70%)

Tyrolian Intake , a/b=0.50 , β =35o 4.5

Width

4.0

L=2.6m B=1.9m

Width and Lenght [m]

Settling basin

Lenght

3.5 3.0 2.5 2.0 1.5 1.0 0.0

0.5

1.0

1.5

2.0

2.5

3.0

Discharge [m 3/s]

Q=1.0 m3/s ÉC OLE PO LY TEC H NIQU E FÉ DÉRALE D E LAUSAN NE

INTAKE Purpose

Civil works

Scope of work

Sluiceway

Intake

9Concrete, Reinforcement

Settling basin

9Form work, Excavation

Next steps

Intake

Structures: Intake+Sluiceway+Side walls+Spillway

350

0

300

2,000

450

0

400 100

250

6,000

150

8,000

100

10,000

300

3

2

200

250 300 200

Form work 400

150 Excavation

100

500

12,000

50

Form work [m ]

200

Excavation [m ]

4,000 Reinforcement [kg]

3

Concrete volume [m ]

350

50 14,000

0 5

10

15

20

25

30

600

0 5

10

River width [m] Con_rock

Con_aluv.

15

20

25

30

River width [m]

Reinf_rock

Reinf_aluv.

Exc_rock

Exc_aluv.

Form_rock

Form_aluv.

Q=0.5 m3/s , a/b=0.5 , β=35o , m=1 ÉC OLE PO LY TEC H NIQU E FÉ DÉRALE D E LAUSAN NE

SETTLING BASIN Purpose Scope of work Intake Settling basin Next steps

Purpose Separate the undesired sediment carried by the flow from the water.

Conventional type Longitudinal settling basin : It consists of one or more chambers of sufficient length to allow the sediment particles to settle down.

Canal

Grids

Settling chamber

Weir

Settling basin Büchi type Transition section Flushing part and Diposition of sediments

Flushing gate

9 It has to be drained almost completely whenever it is flushed out. This may cause disturbance to power production.

ÉC OLE PO LY TEC H NIQU E FÉ DÉRALE D E LAUSAN NE

SETTLING BASIN Purpose Scope of work

Conventional type

Metallic plate

Intake Settling basin, Bieri type

Settling basin Next steps Canal

Grids

Hydraulic system

Settling basin

Flushing device (Metal plates)

Flushing channel

Weir

Flushing gate

9 The Bieri Settling basin ensures energy production even during the flushing procedure.

9 The sediments which settle in the settling basin are flushed vertically through the opening into the flushing channel and back to the river. The flushing water volume is therefore kept to a minimum.

9 Sensors permit fully automatic operation.

ÉC OLE PO LY TEC H NIQU E FÉ DÉRALE D E LAUSAN NE

SETTLING BASIN Purpose Scope of work

Design of Settling basin:

Intake

Length L, width B and depth H of the basin must fulfill the following conditions:

Settling basin Next steps

L≥

Q vD ⋅B

Grids grille tranquilisatrices

VT < Vcr B<= 2h (typically 1.25 to 1.50h) B<= L/8 B : basin width (m) canal Channel Q : design flow (m3/s) d’amenée (section VD : settling velocity (m/s) rectangulaire) VT : mean flow velocity (m/s) Vcr : critical flow velocity in basin (m/s)

Flushingde device (Metal plates) dispositif dessablage, purgeur

h

t → JS

→ retour rivière Back àtolariver

Flushing channel chenal de purge L dessableur Settling basin

transition

vanne de purge Flushing gate

Js=3%

Settling velocity Design grain size : 0.2 to 0.3 mm Empirical formula of Zanke is used for Settling velocity

Recommendations:

B

h t

4 5

a

Extension of the calculated basin length by 10% to 20% in b order to compensate the excessive turbulence in approach flow.

Decision upon having two or more basins instead of one for high discharges

dispositif de dessablage, Flushing device purgeur chenal de purge Flushing channel

ÉC OLE PO LY TEC H NIQU E FÉ DÉRALE D E LAUSAN NE

SETTLING BASIN Purpose Scope of work

Geometry of sediment trap

Intake

Width and Height of settling basin for different design discharges (0.25 to 3.0 m3/s).

Settling basin Next steps

Design grain size as 0.2 and 0.3 mm has been considered.

4.5

5.0

d=0.3mm

d=0.2mm

H=2.3m

4.0 width and Heightof settling basin [m]

B=2.9m

width and Heightof settling basin [m]

4.5 4.0 3.5 3.0 2.5 Width Height

2.0

3.5 3.0

B=2.65m

2.5 Width

H=2.15m

2.0

Height

1.5

1.5

1.0

1.0 0.0

0.5

1.0

1.5

2.0 3

Discharge (m /s)

Q=1.0 m3/s

2.5

3.0

0.0

0.5

1.0

1.5

2.0

2.5

3.0

3

Discharge (m /s)

Q=1.0 m3/s ÉC OLE PO LY TEC H NIQU E FÉ DÉRALE D E LAUSAN NE

SETTLING BASIN Purpose Scope of work

Geometry of sediment trap

Intake Next steps

Design grain size as 0.2 and 0.3 mm has been considered.

Length of settling basin for different design discharges (0.25 to 3.0 m3/s).

55

L 50 45

L=35m L=24m

Lenght of settling basin [m]

Settling basin

40 35 30 25

d=0.3 mm

20

d=0.2 mm 15 10 0.0

0.5

1.0

1.5

2.0

2.5

3.0

3

Discharge (m /s)

Q=1.0 m3/s ÉC OLE PO LY TEC H NIQU E FÉ DÉRALE D E LAUSAN NE

SETTLING BASIN Purpose

Next steps

Weight of steel bars [kg]

Volume of concrete is estimated for different design discharges (0.25 to 3.0 m3/s).

Reinforcement of concrete has been estimated for different discharges (0.25 to 3.0 m3/s).

400

0

Con. St. Power (St.) Power (Con.)

350 300

2,000 4,000

1.2903

St = 3433.5Q

250

6,000

2

R = 0.9998 200

8,000

d=0.3mm 150

10,000

100

12,000

Con = 85.836Q

50

Reinforcement [kg]

Settling basin

3

Intake

Volume of concrete [m3]

Concrete volume [m ]

Scope of work

1.2903

14,000

2

R = 0.9998

0

16,000

0.0

0.5

1.0

1.5

2.0

2.5

3.0

3

Discharge [m /s] ÉC OLE PO LY TEC H NIQU E FÉ DÉRALE D E LAUSAN NE

SETTLING BASIN Purpose

Form work surface of concrete is estimated for different discharges (0.25 to 3.0 m3/s).

2100

0 0.8807

Form = 500.56Q 2

R = 0.9998

1800

200

1500

400 2

Next steps

Excavation volume is estimated for different discharges (0.25 to 3.0 m3/s).

Form work [m ]

Settling basin

Form work surface [m2]

3

Intake

Excavation volume [m3]

Excavation [m ]

Scope of work

1200

600 Exc. Form.

900 600

Power (Form.)

Exc = 466.1Q1.3473 R2 = 0.9999

Power (Exc.) 1000

d=0.3mm

300

800

1200

0

1400

0.0

0.5

1.0

1.5

2.0

2.5

3.0

3

Discharge [m /s] ÉC OLE PO LY TEC H NIQU E FÉ DÉRALE D E LAUSAN NE

SETTLING BASIN Purpose Scope of work Settling basin Next steps

Total cost [CHF]

1,000,000

9Concrete

900,000

9Reinforcement

800,000

9Form work

700,000

9Excavation 9Study of SHP 9Site installation

Total cost [CHF]

Intake

1.2652

Cost = 242400Q 2

R = 0.9999

600,000 500,000 400,000

Total cost

300,000

POPEHYE Power (Total cost)

200,000 2

For different discharges (0.25 to 3.0 m3/s) and design grain size (d=0.3 mm)

POPEHYE : 5000F/m

100,000 0 0.0

0.5

1.0

1.5

2.0

2.5

3.0

3

Discharge (m /s)

Concrete Reinrforcement 3 Kg m CHF 250 2.5

Excavation 3 m 250

Form work 2 m 50

Study Installation % % 10 30 ÉC OLE PO LY TEC H NIQU E FÉ DÉRALE D E LAUSAN NE

NEXT STEPS Purpose Scope of work Intake Settling basin Next steps

Forebay and Penstock Validation of the work concepts by engineering companies Typical maps for a series of discharges Construction details Optimization process and upgrade of POPEHYE

ÉC OLE PO LY TEC H NIQU E FÉ DÉRALE D E LAUSAN NE

Thanks for your attention!

ÉC OLE PO LY TEC H NIQU E FÉ DÉRALE D E LAUSAN NE