Scott CraigCody Maher

Jesse RossBrian Vanstratum

Problem Statement How much power is in water flow? How do we generate power from water? How much power do we need? The Site Data From the Site Available Power vs. Needed Power

Feasibility study Can we make enough

power, using this water source, to provide enough energy for one or more homes?

Located in Reynolds, GA Is a large pond with a

dam on one side Minor Mill Pond is a

watershed for Panther Creek and a collection of artesian springs

Maximum power from water flow depends on the flow rate and the pressure

The pressure is essentially the height the water falls, also called “head”

Thus the equation for max power is:P = mdotρgh, where mdot = mass flow rate and ρgh = water pressure

Turbines are used to generate power from water flow and water pressure

There are 3 main variations on hydro-turbine design

Fully immersed in water Convert water flow to

energy Work like a propeller Typically used in high

flow/low head situations

Operate in air Convert water pressure

to energy Driven by high velocity

jets of water Typically used in low

flow/high head situations

Cross-flow turbine Not entirely immersed

in water Generally operates like

an Impulse Turbine, but also converts water flow to energy

Typically used for low head/high flow

Blender: 300W Coffee Maker: 800W Washing Machine:

500W Dryer: 5000W Central A/C: 2000 –

5000W Wall A/C: 1000W

Typical residential power requirements:

Aerial view of the pond View of dam and mill house

Minor Mill Pond

Spillway One

Spillway Two

Dam

Natural Spillway

Runoff

Pond side Opposite side

Pond side Opposite Side

The Minor Mill Pond runs to the Patsiliga Creek which then dumps into the Flint River

The USGS has two gage stations monitoring flow rate one north of our site and one south of our site

By utilizing this data we can roughly estimate the flow from the surrounding tributaries

Gage Station Data from the year 2004

The two stations show the average stream flow (Cubic Feet per second) for each month in 2004.

By taking the difference of flow rates we can determine the tributary contribution.

The flow from the Minors Mill Pond will be a fraction of that contribution.

We can then generate a fraction that represents the flow contribution from our site based on the flow rate data we collected on September 30th

2006.

dt 1

1.6

1.9

1.4

1.7

1.3

1.45

1.45

1.6

1.5

1.76

1.71

1.3

1.7

1.9

1.45

1.45

1.6

1.4

1.4

1.4

s x 12 in

Average velocity at the surface of the flow

To calculate the flow rate we need the average velocity of the flow

Neglecting the friction due to air, the velocity at the surface of the flow is the maximum value of the velocity distribution of the centerline of the flow.

A look at some hydraulics texts reveals some useful equations…

vavg1

nRh

2

3 S0

1

2 Manning formula for open channel flow

vsurface vavg1

kvonKarmen

g h S0 Vanoni velocity distribution for open channel flow

We never measured the grade, SO but by virtue of two equations we can find it.

0 0.05 0.1 0.15 0.20

0.1

0.2

0.3

0.40.379

1 103

y

0.1970v avg

1

k vonKarmeng h S 0 1 2.3 log

y

h

.1 m

h

yu y( )

d

h .1 m( )0.133

m

s

Applying same methods from before:

v2 avg 0.376m

s

Vdot1 804gal

min

Vdot2 1875gal

min

Vdottotal 2678.7gal

min

In order to minimize environmental effects we only want to use half the flow from spillway two

Vdotusable1

2Vdot2 Vdot1

Vdotusable 1741gal

min

water 1000kg

m3 h 8.33ft

Pmax Vdottotal water g h

Pmax 4.209 103 W

50%

Pusable Vdotusable water g h

Pusable 1.368 103 W

Pmonthly Pusable 31 day

Pmonthly 1.018 103 kW hr

Determine what we can power with a middle Georgia micro hydro site

Very small neighborhood (7500 kW*hr/month) Just one house (1500 kW*hr/month) Preliminary useable power = 1018

kW*hr/month

Decision Matrix

Options Cost Reliability Power Generated Environmental Impact Totals

*Max Power (Two Feet of Additional Head) 2 8 10 2 22

*Max Power (Current Head) 3 9 9 2 23

Spillway 2 Preservation with Renovation 3 9 6 8 26

Preserving Existing Dams 7 4 2 10 23

75% Reduction in Spillway 2 Flow

(Renovation) 3 9 8 6 26

*Max Power = Closing of Spillway 2 for max flow