d
capacitors to provide excitation for the motor/generator, it works surprisingly well!

In the village were getting a steady, regulated 228 volts output at 54 Hz. While we found
we could generate up to 3 kW (7.5 amps at 400 volts at the generator), weve throttled it
back to about 1.6 kW to keep more water in the stream.

This project involved collaboration by a lot of different groups: residents of Huai Kra
Thing village, the Border Green Energy Team
1
(BGET), ZOA Refugee Care, students
from the Engineering Study Program (ESP) in Mae La refugee camp, students from the
Institute for Village Studies and Spring Street high school in the USA, Bikash Pandey
(Winrock Nepal) and Robert Landau. The project was funded with contributions from the
UNDP/GEF small grant program, the Robert & Patricia Switzer Foundation, Green
Empowerment, and the Institute for Village Studies.

Work on site started on the last week of January 2006 with villagers (under the direction
of Surat, Watit, Polchai, Andrew, and Yoteen (BGET)) clearing two different possible
headrace/penstock routes. Villagers, Polchai (ZOA), and Chris (Palang Thai) made the
final selection based on concerns that the other option would have required construction
on an unstable slope that risked pipe breakage in the long term. The final choice did
require considerable civil works: a 5-meter deep trench through about 30 meters of
hillside, and an extended pipe elevation section for 50 meters that also crossed over the
stream.

Every day 20 villagers came out to work. We also had 6 wonderful students from the
Mae La Refugee Camp Engineering Studies Program (ESP). Chris arrived with a group
of 8 US college students from the Institute for Village Studies on 1 Feb, and halfway
through the week the college students were replaced by an equal number of high school
students from the Spring Street high school in Washington State, USA.

Polchai and Andrew directed work on the dam. Surat directed work on the pipeline.
Yoteen led a group doing village wiring. Watit provided logistics, coordination, and
political relations support. Chris worked on the power house with BGET volunteer
Stephen Brink.

Power house work was slowed by a 2-meter diameter log wedged from bank to bank just
upstream from the planned powerhouse site. We felt that there was a significant chance

1
BGET is a joint project of the Taipei Overseas Peace Service (TOPS), Palang Thai, Green Empowerment,
the Karen Network for Culture and Environment. the log might come loose in a wet season flood and crush the powerhouse. Villagers and
students worked together to cut the log in half with a two-person cross-cut saw and an
axe. We were able to push one of the pieces downstream somewhat, but the other
remained a hazard. We decided to move the powerhouse slightly downstream to avoid
getting crushed during a flood by the remaining section of log, which was still wedged
somewhat precariously.

Drawing on Charleys (group leader from the Institute for Village Studies) and the
villagers cement expertise we made a cement pad roughly 1.5 meters * 1.5 meters for the
generator/turbine, and built a powerhouse around it. The generator/turbine was bolted to
six 7/16 diameter bolts sunk in the concrete.

Power is produced by the 4 kW motor run as a generator. To provide excitation we used
two capacitors, one valued 50 uF and the other 25 uF in a C-2C wiring arrangement
with 50 uF on one phase, 25 uF on another, and none on the third (Figure 1). We then
drew single-phase 380 volt power off of the 25 uF phase. We transmit the 380 volt
electricity about 500 meters to a control house near the village school. There, the
electricity is transformed by a custom-made 380 volt-to-235 volt 3 kW transformer. A
Nepali-made electronic load controller (ELC) shunts excess power to a bank of three 1
kW ballast resistors (heating elements). The regulated 220 volt power then is transmitted
throughout the village to the clinic, school, community center, two churches, and village
headmans house on a set of single-phase, insulated aluminum wires.
15A
10A
To
Village
Total
Current
235V
3000W
ELC
Ballast
Current
3kW
Ballast Load
380V
Motor Run
Capacitors
in Box
6A
4 kVA 380V
C
25�F
2C
50�F

Figure 1: System schematic. The system uses a C-2C capacitor arrangement to provide single-
phase power from a 3-phase generator. We transmit power at 380 volts, and step it down to 235 volts
near the village. A diversion load controller ensures that voltage is constant.

The final evening after the project was commissioned we had a big party with Karen
villagers, American students, Swedish volunteer Fredrick Bjarneg�rd, Sam Lai (TOPS),
local Forestry Department officials, and a group of Taiwanese computer university
students. Amid the festivities, we lit up by the micro-hydro project, the villagers
successfully powered a 4-inch power planer using electricity from the project.

The photos below tell the story better than words:



Figure 2: Trench for headrace pipe cut by villagers. The trench extends for about 20 meters.


Figure 3: Sediment trap


Figure 4: Villagers carrying the >100 kg turbine/generator about 0.6 km to the site.

Figure 5. Surat sets bamboo form boards for cement pad that will hold the generator/turbine.

Figure 6: Chris poses by generator/turbine, now bolted to the cement pad. Chris left hand rests on
the pump outlet, which will serve as the inlet when operated as a turbine.
Figure 7: Saw Sunday and Naw Gigi from the Mae La refugee camp ESP program wire the three-
phase 400 volt motor/generator terminals.


Figure 8: Spring street students and volunteer Stephen build bamboo walls at the powerhouse.

Figure 9: Completed dam. The dam is just high enough to ensure that the pipe inlets are submerged.


Figure 10: Surat, Polchai and Chris connecting turbine to penstock pipe
Figure 11: Connecting the penstock to the generator required careful alignment and some tricky
angles.

Figure 12: Andrew Pascale and Fahren hold the bucket for a flow measurement, while Alice uses a
stopwatch to measure how long it takes to fill up.

Figure 13: Poor communication and a bad glue joint led to a nearly disastrous pipe rupture inside
the powerhouse, completely drenching all the electronics and tools. Amazingly, no one was hurt and
almost of all of the electronics were unharmed.

Figure 14: Water outflow at tailrace (10 liters/second) when turbine is generating 1.6 kW.
Figure 15: capacitor box and switch box at the power house. When the photo was taken the
generator was generating 4 amps at 400 volts. We were able to push it to 7.5 amps (3 kW) but have
decided at this point to let more water flow in the stream since the village does not yet need more
than 1.6 kW.

Figure 16: ELC and ballast load in metal cage.
Figure 17: Andrew worked with Mae La refugee camp Engineering Studies Program (ESP) students
to build solar ovens tested on the final day of the project.


Figure 18: Lights in the community center powered by micro-hydro


Figure 19: Post project party