Do I have a Hydro Site?

 

This is a complicated question.  The answer depends on many things, such as; permits, your neighbors concerns, environmental issues, enough vertical fall enough volume of water, pipe loss and electrical transmission problems, and of course cost.  Hydro is probably the least expensive way of producing power.  It can be built for, as low as, $2,000 if user installed.  Most folks are not that lucky, figure on spending somewhat more.  The biggest mistake you can make is letting cost govern engineering decisions at this stage.  Let’s look at what is possible from the site and then see what the cost is and then scale it back if you don't need that much power or can't afford that much expense.  After all, hydro doesn't necessarily have to provide all the power you need.  Most systems usually include some solar and a back-up generator.

 

Definition of terms and units of measure

 

Head:         is the vertical component or elevation change between the intake and the hydro-generator measured in feet or pounds per square inch (PSI) of pressure at the nozzle in the hydro.  For those of you on the metric system, you will have to make your own conversions. 1 PSI = 2.31 feet of head. 1 foot of head = .433 PSI

 

Flow:          is the quantity of water flowing through the nozzles in the hydro.  Leaks don’t count.  Most residential sized systems are measured in gallons per minute (GPM).  Larger systems are measured in CFS (cubic feet per second). 450 GPM. = I CFS

 

Static Head:        Head measurement at 0 flow rate

 

Dynamic Head: the "net" head under actual working conditions.  This # is always less than static head and is a result of friction losses in the penstock.  

 

Volts:          is a unit of electrical force

 

Amps:        is a unit of electrical current or volume

 

Watts:        is a unit of power and is a product of amps times volts, for example: 4 amps at 12 volts = 48 watts.

 

Ohms:        is a unit of electrical impedance.  Ohms law states that 12 volts through 4 ohms impedance will allow 3 amps of current to flow.  It will be necessary to understand voltage drop in a run of wire and Ohms law is fundamental.

 

KWH & AH:         By convention: amps, volts, and watts are instantaneous measurements of electrical energy.  Over time, we commonly use: watt hours, kilowatt hours, and amp hours.  Since the voltage on your home system is of one voltage and relatively constant it serves no purpose to use the first two terms, at least on the DC side of your electrical system.  Amp hours is easier to understand and keep track of, for example, if the hydro is  producing 5 amps for 24 hours you have produced (5 X 24) Amp hours into the battery to be used by an inverter, DC or appliances.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

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