A work crew of seven rallied to the Mendicino Ecological Learning Center to complete a number of projects on the 1800 Watt micro hydro system. We began the day with a divide and conquer game plan in order accomplish as much as possible with the amount of time volunteers had to offer today.

New to the project were Carlos and Tim. They came prepared and set to work digging out the spot where the screened intake box will be installed. The work involved digging a shallow hole with a pick and leveling the ground with a shovel. When the box is placed into the water rock will be set against it to secure it in the hole. As you will be able to tell from the picture the two men were able to get into the drainage and work with relative ease due to the minimal amount of water currently in the drainage. Locals are considering this a “special occasion” because December usually brings a lot of precipitation and more volume and flow to the site. This unseasonably dry and sunny weather is the main reason we are able to proceed with a micro hydro project at this time of the year.

Max and I worked together to connect three-inch hard pipe to the intake box. We connected two sections of twenty foot long pipe. At the end of these sections we will put a Y-joint that will split the flow into two and reduce the pipe diameter into two-inch. This reduction in diameter is intended to increase the pressure in the lines.

Ben joined with Carlos and Tim to carry the hydro-turbine down to the site in which it will be installed and generate electricity. After Max and I arrived to the site of the hydro turbine, Max decided where he wanted the installation. We dug a hole the width of the barrel that the generator is sitting on and to a depth of about two and a half feet deep. The turbine was placed inside a hole and backfilled to firmly secure it in that location. We dug an additional trench and installed a length of flexible tubing to the bottom of the turbine housing that is intended to redirect the water back to the stream once it winds through the generator.

Ben worked by himself to cut off bent, inflexible portions of tubing with the intention of uniting them with straight sections. He used two hose clamps on each side of the connection to guarantee a secure union. The reason the end sections needed to be cut off was because the hose had been pre-coiled for so long that it would not relax at the end. When we made connections with the bent line it was awkwardly and incompletely attached, and therefore, did not appear secure. When the bend was cut off we could be more confident that we had ensured a quality connection of the lines.

While Ben was connecting the tubing together, Gerry, and I rounded out the day by designating the final path of the water transmission lines. We wanted to make sure that the lines did not overlap on top of each other and that they followed as direct a path as possible-always flowing downhill. We pounded steel rebar stakes into the ground and tied both lengths of tubing to the rebar with doubled over, thickened wire. Our best asset in securing the path of the tubing was using natural objects such as live trees, fallen trees, and rocks. These objects are heavy and rooted in the hillside. They will act as the best option for securing the tubing and keeping it out of the drainage.

Tim and Carlos Digging Spot For Screened Intake Box (Unseasonably Dry Conditions)

Screened Intake Box With Forty Feet of 3-inch Hard Pipe Attached

Hydro Turbine Placed Inside Its Hole to Secure it In Place

Example of Bent Connection (We Want To Avoid This)

Example of Using a Natural Anchor To Secure Water Transmission Lines

There was nice weather today to begin what I consider nothing short of a rodeo. After marking the path that the water transmissions line were to follow, it was time to lay out the tubing. We are using rolls of 2-inch in diameter polyethylene tubing rated to 80PSI. The tubing is used to take the water out of the stream and channel it down into the turbine where it is then returned back to the stream. Starting from a level spot about 700 feet uphill we began to unroll the transmission lines.

We had a hardy work crew of three ready to undertake the project of laying the lines from start to finish. The project is like a rodeo because the 300ft rolls each weigh about 170-200lbs and are made of polyethylene, which when cold and pre-coiled for a number of months does not want to easily relax into a flat path. The tubing is slippery when wet and can really be a trial to move. However, we had skill on our side, because Ben possesses an uncanny ability to judge how a roll will uncoil without creating significantly tensioned bends. I cannot explain how he can see this; however, we would orient the roll the way Ben suggested and work together to unroll it. The rolls can be handled by two people, but it works quite well with three. Although we only need to cover 700 ft, we are running two transmission lines. This means that we actually laid out 1400 feet of tubing!

When we are done placing the tubing we walk back and make sure it follows the contour of the land so that we can take advantage of two specific things. First we want to stay with the contour of the natural landscape to ensure that the pipe is moving as downhill as possible. The second thing to take advantage of are natural supports including live and fallen trees, stumps, and rocks to anchor the tubing and make certain that it does not fall into the drainage. We hope that the pieces of steel rebar that we drive into the ground also hold the pipe in place; however, I personally have my doubts. This is because most of the land that we are walking on is primarily rock that has had years of erosion deposit very unstable and shallow loam soil. We pound into the soil about 8-10 inches then hit solid rock. That is why utilizing trees and rocks as our anchors will be the best long term bet when determining the permanent path of the water transmission lines.

When the day was done we were able to lay out all of the water transmission lines, from intake site to the turbine site. When work resumes the goal will be to connect the lines together, install the screened intake box, and connect the hard 3-inch pipe that extends from the intake box into a Y-joint and to the 2-inch tubing.

Christoffer and Ben Rolling Out Tubing

Three of Us Having a Rodeo As We Fit The Tube Between Two Trees

Two Tubes Laid Out By Hand (Better Than a Machine Could Do)

In Places Like This We Could Move The Rolls On "Tube-Tracks"

As part of our efforts to help communities adapt to an energy constrained world, the Post Carbon Institute is teaming with community members to support and facilitate the creation of alternative energy sources. This time, Christoffer Hansen, Energy Farm Development Specialist for the Post Carbon Institute, headed for the hills to consult and participate in the installation of a micro-hydro system. The energy generator, a Harris impulse turbine, is located some 700ft below the intake box, fitted with four nozzles ready to deliver up to 1800 Watts of continuous energy. The water source for this turbine is located on private property and utilizes seasonal rain runoff. The water enters a screened sluice (intake box) connected to a 3-inch tube, runs about 20 ft and hits a Y-joint splitting the flow into two 2-inch polyethylene tubes that run the full length down, down, down, to the water turbine. When the water reaches the turbine it is again channeled into 1-inch tubing that finally shoots water out a ¼-inch jet. The jet stream(s) of water shoots onto a wheel. This wheel is connected to an alternator and spins very fast, generating electricity. The electrical output is 440 Volts, which is considered high voltage. The high voltage is necessary because the electrical transmission lines travel about a half mile from the turbine to the inverter and battery bank at the Mendicino Ecological Learning Center.

Today we worked under scattered showers to initiate the sighting and installation of the water transmission routes, pipes, and intake box, and turbine. We carried down the final two rolls of 300ft long, 2-inch polyethylene tubing. As mentioned above, the system splits the water flow into two pipes. Therefore, there is a total of over 1400 ft. of tubing that needs to be laid and spliced together. After dropping off the rolls we set out to locate the site of the turbine and begin determining the path, uphill, to the intake box.

This process involved finding the straightest water transmission route possible from the spot of the turbine to a place up stream with higher elevation. The ultimate goal here is to pick a path that eliminates any large curves or rises in the pipe so that the turbine is rammed with the smoothest, most direct flow of water possible. After determining the final descent to the turbine, we kept walking upstream (uphill) placing flags at 50-foot intervals along our desired route. We would always look behind us to be certain that the flag we were about to plant was above the flag sitting 50-feet behind us. Finally, we reached a level spot where the water begins its descent down the 700 foot drainage. This level spot is where the screened intake box will be installed.

Crucial choices that had to be made involved deciding whether or not to start the transmission lines higher upstream where natural geography could have compromised the velocity of the water flow. We decided against starting higher upstream because there was some uphill spots to navigate and places where the lines had to cross the drainage in order to maintain the downhill path toward the turbine. When sighting water transmission lines it is not length that is important; instead it is vertical drop. We opted for the most level spot to place the intake box and secure a sure cascade down the drainage.

Welcome to the Mendicino Ecological Learning Center!

Four Nozzle Impulse Turbine (1800 Watt max output)

Ben and Max Ready To Take 300ft Roll To the Site

The Site of the Intake (The Beginning of the Descent)