DoradoVista - Small Hydro Power Project:

The goal of this Small Hydro project is to produce alternative energy to be used for powering the DoradoVista ranch with a surplus of Renewable Hydropower Energy to potentially sell on the grid:

For a great primer on Small Hydro Power (SHP), take a look at these "pdf" files from the "European Small Hydropower Association":


Small Hydro Power Guide Part 1:
Part_1_Guide_on_how_to_develop_a_small_hydropower_plant-_Final.pdf

Small Hydro Power Guide Part 2:
Part_2_Guide_on_how_to_develop_a_small_hydropower_plant-_Final-2.pdf

 

Note: These 'pdf'  download files are pretty big at about 100 to 200 pages each. Be ready with the bandwidth and disk space.  They have lots of cool graphics, explanations and pictures even if you don't understand the engineering math.

The ESHA Small Hydro Guide is by far the best guide I have found with regard to setting up a small hydro and many of the issues that surround successful renewable energy generation.  Take a look at the European Small Hydropower Association --ESHA web site for lots more information*, even if you aren't looking at setting one up.  Of course each region of the world has its own set of issues and regulations to work out as well.  I'll be providing more on that later.

For recent Small Hydro Power News see this page:  www.DoradoVista.com/Hydro_News.php

The technology and science of Small Hydro power is quite interesting on its own merit. Our system design is based on an instream or "run of the river" Hydropower model in which the water diversion is very small and allows fish, water and material to bypass the hydro generator intake. The intake draws in a sufficient amount of water to generate power while passing the remaining flow down the original Instream path including major floods.

Simple Hydro Power model:

    (Head(ft) x Flow in Cubic Feet per Second) / 11.8   = P = KW output.  or
    (Head(ft) x Flow in Cubic Feet per Second) / 8.8     = HP output. 

    Then take KW output x Hrs producing x Generating Rate ($/KWH) =  $

Keep in mind that the actual power generated here will be reduced by friction and electrical losses by some 15% or more depending on the mechanical and electrical efficiency of the actual hydropower equipment installation. You must include this efficiency factor in any Hydropower design model for it to give a good economic return on investment or ROI. This is a common place to make a mistake when considering the purchase of Small or Micro Hydropower equipment.

The planned DoradoVista Ranch system is based on a renewable energy resource; "Run Of River" Hydro power. The water is not stored except for head regulation and intake requirements, any excess water passes the intake and continues downstream also known as "Instream hydro power." There is also an instream flow requirement that sets a minimum flow for continued health of the stream critters between the intake and power house. 

In our case we will start with a Canyon Hydro -- 350 kW Pelton wheel shown above. This unit has a 350KW GE induction generator with servo control and grid switching gear. It is a 28 inch pitch Pelton wheel with a single 4.125 inch dia. nozzle (3.5 in effective jet) which can be upgraded to a two jet unit for more flow and therefore power.

Our potential head (intake to outlet height difference) is less than the Pelton turbine design head so we will seek to increase water flow rates to partially compensate for power output loss. Increasing flow is not as effective as increased head, so we should seek any means possible to increase head first, then optimize the Hydro system for more flow.

To adjust the hydro turbine generator speed we will need to change gear ratios in the reduction gearbox so the flow velocity to Pelton Wheel RPM is correct for 60hz. The variable needle jet control combined with the extra nozzle and use of the pelton turbine gives us a better range of efficiencies for our variable instream flow regime. A crossflow hydropower generation unit or possibly a francis turbine would probably be a better match for the lower head, but they have less efficiency over such a wide range of flows. Again efficiency is important for our ROI to be decent.

Another concern for overall hydro generator system efficiency is the maintenance of minimum flows as shown in a variable stream Flow Duration Curve or FDC. An FDC shows the historic flow levels vs frequency of occurance in a max to min pareto chart. These FDC charts are used to determine the right size of Hydro generator system, Weir and Penstock size. Many streams have flash floods that would be impractical to harness due to the low frequency of occurrence. This is usually at the point where economic return for larger penstocks and generators cannot be justified. For example our creek shows this type of pattern. It would take a 15 MW generator to harness the peak flows every 3 years, but the need would be for less than a few days. Thats not cost effective.

With Run of River designs a basic principle is to retain the ecology of the stream bed while tapping into extra instream energy in the higher stream flows when they exist. Good Turbine to Generator efficiency allows us to tap energy right down to the minimum residual stream flow and still get the energy out economically. Below the minimum instream flow we let the remaining water pass by the system. This practice retains the balance of flora and fauna in the stream reach between the hydropower system intake weir and turbine outlet at the power house. It may mean that the system turns off annually based on rainfall and snow patterns.


The goal is to produce renewable energy with Net Zero green house gas and a minimum of ecological impact.  Just add water! Our DoradoVista Ranch creek has a history of sufficient flows for a significant part of the year such that it should reasonably generate predictable electric power for about 9 months per year. The 3 month late summer season will typically be used as down time for maintenance of the equipment. This will maintain a minimum instream flow to keep the creek ecologically balanced and healthy.

The ranch property owned by DoradoVista,  Inc. has a significant portion of the available head (170 ft out of a total of 350 ft) and water flows sufficient to be considered as a likely site for small hydro development, according to the "Idaho National Labs – INL, Hydro Power Prospector".  The INL web site has more on hydropower prospecting:  http://hydropower.inel.gov/prospector/index.shtml 

This is a great renewable Small Hydro energy resource provided by the US Government, take a look at the GIS driven resource maps for an area.  Drive it around and get the feel for the many prospects and limitations for Small Hydro in the future.  The site rates a solid five stars by DoradoVista Inc!

The Financial Goal of our Hydro system cash return is to Break Even in < 7 Yrs (BET)
       -- Model does not include finance costs otherwise so, expect typical 10 yr commercial return.
       -- System should return $ ~predictably over 5 yr interval. 

Just as Farmers know, rain is 'an act of God.' There will be times of low flow and low return of capital. The plan is to target a reasonable likelihood of return over the 5 year timeframe. By sizing penstock and support infrastructure costs accordingly this should be achievable.

The key to any Hydro success is to set up statistically optimized cash flow structure such that the system is economically viable.  We will need to keep a good multi year model of production and a good capital and operating expense budget to match! 

Save that cash from peak rainfall years to help make up for missing cash flow on low years. Our used 28 inch Pelton wheel and 4 inch jet are shown in the pictures, for scale my son is standing next to the Canyon Hydro Pelton turbine housing.

Instream hydro, Small and Micro Hydropower based on a Run of River design are the most efficient and ecologically balanced renewable energy systems available today. They are typically 4-5 x better cost to energy output and corresponding reduction in total emissions including manufacturing and installation than other renewable technologies. The key is balancing instream flows and impact against the return on investment for the total installation. Other renewable's require much higher subsidies and regulation burden reduction to come even close to the value of Small and Micro Hydropower system.

Another potential is to use the Hydroelectric power to replace expensive onsite Agricultural power usage. This will save us between 2 and 3 times the $/KWH value of the electric power we would otherwise be importing. As part of our overall plan we will be using Hydroelectric power to supply irrigation pump, process and cooling power for our berry ranch. Then the excess power will be made available for open market sales again to help support our berry ranch projects.

Don't forget to visit our Gold pages, you can start at:  www.DoradoVista.com/Prospecting_Tools.html

* You can find more material from ESHA on  SHP at the following resource web site: http://www.esha.be/