Micro-hydro 2004

Dominica Micro-Hydro Installation

Spring 2004 EE 186/195; By Alvin Chan and Adam Meil

*** BACKGROUND INFORMATION IS GIVEN AT THE END OF THE WEBSITE: WE BEGIN WITH WHAT HAS *** *** TAKEN PLACE SINCE THE FINAL PRESENTATIONS IN THE FALL OF 2004.

Micro-Hydro

Training

On December 19 the group of students that went to Dominica received a free workshop giving a basic walkthrough and day to day itinerary for the installation of the pipes, turbine, and entire micro-hydro system. This training also provided everyone with a chance to get familiar with some more of the materials. The generator, turbine, Electronic Load Governor, and several other of the materials needed were all brought and divided up in order to bring to Dominica safely and legally.

Workshop

Turbine Unit

Generator

Electronic Load Governor (Closed)

Electronic Load Governor (Open)

Fighting the Muck

Walking the Pipeline

Flagging the Pipeline

Flagging at point of Foundation

Intake Tank - The water from in the intake tank is taken from naturally running water at a higher elevation. The entire water source is not nearly used completely

and there is no water shortage. The intake tank does allow a lot of water to flow out of it into the stream at all times. The hydroelectric complex

takes the water they need for use in the turbine and sends the rest back to the stream.

Water Pipe - This is the water pipe used by DOMLEC. It is 18" in diameter, yielding an extremely large potential flow.

Step Up Transformer - A wire from the generator first goes to a step up transformer to get the desired voltage, in this situation 11000 volts.

Old Trafalgar Turbine Unit & Valve Components - This is a picture of the original trafalgar turbine unit which was installed about 60 years ago and it looks very

similar to the unit that we are using, only on a larger scale. The valve components are very similar as well in this turbine. The main difference between

this system and the system that we installed is that our system had an ELG and this turbine used a (Mechanical) MLG.

Pressure Valve - From the pressure valve calculations as to how much power is being produced can be made. The idea is that the pressure valve stays the same

because of the load governor.

New Trafalgar Turbine Unit - This system was set up around 20 years ago and is well advanced from the previous system. The load governor is hydraulic and this

turbine unit is the one that is currently up and running at the hydroelectric complex. Again, this is very similar to the turbine that we are installing in

everything other than magnitude.

Control Room - This is the control room where troubleshooting and all that data is collected for the output of the turbine power. There was someone working in this room at all times sending and receiving data to the other DOMLEC power plants on the island.

Joint 1 - This is where the initial joint was, coming out of the intake tank. We felt that this was one of the most important points of the entire process because we had to put a joint in right away and there was a lot of instability here. We also needed to put a butterfly valve at this point so we could turn the water on and off as we pleased.

Intake & Joint 1 - In this picture you can see the intake tank and the pipe initially going out of the intake tank. It is clear to see in this picture that a maximum amount of flow through the 4 inch pipe is being used.

Joint 2 - This is about 1/3 of the way down the pipeline where there was a walkway crossing. We needed to dig to bury the pipe across the walkway and we needed two joints right after one another in order to run the pipe successfully. It is easy to see in the picture how supports were used and thrust blocks to keep the pipes stable under strenuous conditions.

Pipeline 1 - This is a picture of the pipeline 20' following the first joint. As is seen in the picture, the PVC pipe does bend some. This saved a lot of joints on the way down because the situation of having a straight pipe did not turn out to be ideal in this situation.

Turbine in House - In this picture Peter, a partner of ours, connects the valves of the turbine to the turbine inside the house.

Turbine Pipe Connection - This picture shows the pipe connected to the turbine. Note that the pipe does not go directly into the turbine. This was one of the biggest issues because we were unable to come up with a way to get the pipe to go straight into the turbine.

Clean Out & Flow - This picture shows the cleanout just prior to the foundation and also shows the flow at the bottom of the hill.

Pressure Gauge - Here the pressure gauge shows the pressure of the water through the 2 inch diameter pipe when the butterfly valve is opened at the intake tank.

ELG & Transformer Connected - This is the room after the ELG and transformer are connected.

After all of the pipes were laid down and sealed they were allowed to sit for 24 hours so the concrete from the supports and thrust blocks could dry. The only things left to do at this point was to install the turbine in its "house", connect the valves to the turbine, and wire everything up. The wiring is connected from the turbine and goes through conduit up to the electric room, at the top of the hill where it is then connected through the transformer to the ELG. The ELG then is able to govern power to the guesthouse and the dump load. The following pictures show in detail the ELG and the turbine and its valves.

The other major part of the project was to lay down the pipe from the intake tank, at the top of the hill to turbine at the foundation of the bottom of the hill. We found from the previous part of the project the line where we would be lying the pipe so the steps were simply to lay down the pipe to find out what sort of joints would be needed and to have an idea of what sort of problems we would run into. We found that the major problem in laying the pipe would be trying to stabilize the joints and the points at higher pressure.

Dump Load - Because all of the power from the turbine is not always needed a dump load has been set up. This is where extra power, governed by the ELG will be 'dumped'. The water will become very hot and is dangerous due to its high voltage.

Turbine Movie

Tasks for March, 2005: 1. Fix Final Pipe Joint - As can be seen in the picture, the final pipe joint is not attached properly and is very unstable. Upon returning we must make this final piece of the pipe stable.

2. Tighten Turbine Valves - As could be seen in the movie, there are leaks in valves of the turbine. These need to be sealed and taken care of so that a maximum flow can be taken by the turbine.

3. UV Paint - The PVC pipes that we used are exposed to sunlight and therefore will deteriate over time. Our plan is to paint them either with special UV paint or just to paint them a certain color in hopes of keeping them from deteriation.

4. Dump Load Consideration - The dump load does not necessarily need to be just wasted power. It could be used as a heating element for pretty much anything, perhaps a hot water heater in this situation.

At the conclusion of the time spent at Dominica there was a closing ceremony. At this closing ceremony were a wide variety of people. While all of the participating students were there, there were also members of the countries government as well as several representatives from DOMLEC. All of these people spoke and the media was there to cover the event. At this point, though, the task was not yet completely done and therefore we are going back to Dominica to finish the final tasks during spring break 2005.

The first step of the micro-hydro installation process was to cut or dig a line and flag for the pipe to travel from the intake tank to the place where the foundation was to be built. This was done on the very first day and gave a good idea as to how much pipe was needed and where the pipe was to be laid. This was met with some difficulty. We had previously thought we would be able to dig but quickly found out the terrain would not allow for digging in many places. The flagging was supposed to take the entire group 3 full days. We finished in about 1 day, before the group of local students even arrived to join. When the local students arrived they were put through a similar workshop to the one we were exposed to on December 19. This was led by Alvin Chan and gave the group of Dominican students involved an idea of what we were going to be doing.

While in the country we were lucky enough to be able to take an in depth tour of one of the island's hydro-electric plants. DOMLEC, the countries sole provider of energy, showed us there system. This plant supplies about 20% of the island with power. There system actually turned out to be extremely similar to what we installed at the guesthouse, only on a much larger scale. The following are pictures from the trip to DOMLEC's hydro-electric power plant.

A major component of this project was in the building of the foundation. There was no flat land near the foundation point so we needed to decide how to build a stable foundation that could protect against both weather damage and security dangers. We decided to design a foundation with 5' x 5' x 6" of concrete with steel beams around the edges. Then, using cinder blocks, making a "house" for the turbine and generator. This "house" was made with a hole for the pipe to connect to the turbine. The foundation took a lot of hard work and materials to build. The foundation was built at the bottom of the hill and all of the materials needed for building had to be carried down there. These materials included 2 tons of sand least 1 ton of stone aggregate, and about 1 hundred cinder blocks. The following pictures will take you through the process of building the foundation.

Students from the UVM and SUNY, led by Alvin Chan went to Dominica in the Eastern Caribbean in attempt to install a micro-hydro power system to a guesthouse on the island. Prior to the trip there were a lot of things that were done to have the goal of complete installation to be successful. Below are links involving planning of the trip, parts, grants, and flow calculation, all done prior to the trip.

Background

Information