1. Stick This in Your Pipe

2. Information Found at the Following Website http://microhydropower.net/index.php

3. Pipe can be a Considerable Cost up to 40%

4. Factors to Consider surface roughness, design pressure, method of jointing, weight and ease of installation, accessibility of the site, terrain, soil type, design life and maintenance, weather conditions, availability, relative cost, likelihood of structural damage.

5. Considerations Pipes are generally supplied in standard lengths and have to be joined together on site. Penstock pipelines can either be surface mounted or buried underground. The decision will depend on the pipe material, the nature of the terrain and environmental considerations.

6. Burying Pipe Burying a pipe line removes the biggest eyesore of a hydro scheme and greatly reduces its visual impact. However, it is vital to ensure a buried penstock is properly and meticulously installed because any subsequent problems such as leaks are much harder to detect and rectify.

7. Types of Pipes The following materials can be considered for use as penstock pipes in micro hydro schemes: –mild steel, –unplastified polyvinyl chloride (uPVC), –high density polyethylene (HDPE), –spun ductile iron, –asbestos cement, –prestressed concrete, –wood stave, –glass reinforced plastic (GRP). PVC and HDPE are the most common used materials.

8. Pipe loss charts modified from Scott Suddreth’s Hydro Matrix Excel sheet

9. PIPE FRICTION LOSS Polyethylene SDR - Pressure Rated Pipe Pressure Loss from Friction in Feet of Head per 100 Feet of Pipe Flow US GPM Pipe Diameter, Inches 0.50.7511.251.522.53 40 21.510.23.021.270.44 45 26.812.73.751.590.55 50 32.515.44.551.910.67 55 18.35.431.960.81 60 21.56.42.70.94 65 23.87.413.131.08 70 28.78.493.591.24 75 32.69.674.071.4 80 10.94.581.59 85 12.25.131.77 90 13.55.711.98 95 156.312.19 100 16.56.922.42 150 34.514.75.11 200 258.7 300 18.4

10. PIPE FRICTION LOSS - PVC Class 160 PSI Plastic Pipe Pressure Loss from Friction in Feet of Head per 100 Feet of Pipe Flow US GPMPipe Diameter, Inches 11.251.522.53456810 40 11.45.891.980.780.30.090.02 45 14.27.342.480.970.370.120.04 50 17.28.923.011.20.460.140.04 55 20.510.63.591.430.550.160.05 60 24.112.54.211.660.640.180.070.02 70 16.65.612.210.850.250.090.03 80 21.37.182.831.080.320.120.04 90 8.923.521.360.390.140.07 100 10.94.281.660.480.180.070.02 150 23.29.063.51.040.370.160.05 200 15.55.961.750.620.280.070.02 250 23.49.052.650.940.420.120.05 300 12.63.731.340.580.160.05

11. Lets do some examples: Turtle Island 140 ft head 4” HDPE (High Density Poly Ethylene) Ok lets do 3” since it is on the chart. What is the best size of PVC pipe to use for 100 gpm with 100’ head? Keep loss below 5%. How about 30 ft head?