basic questions about hydro

[mattpower]

Greetings. There is a decent sized river that runs through my city. There are two dams along the river - one is about 8 feet tall, the other about 9 feet tall. The river is about 10 feet wide in most places, if that helps. I have no easy way of estimating the  gallons per minute, but I do have a couple of pictures and movies (at http://www.mattzone.com/hydro ) & I'm wondering if someone could help me guestimate the power generating potential of these two sites (IE: Kw/Mw output). I know at least one of these dams may be rebuilt (and narrowed) in the next year or two by my local government, and I'm wondering if it's worth suggesting a hydro installation. The local government has been fairly receptive to solar, and is building a 10 megawatt  waste-to-energy electric generation facility [ http://www.house.gov/shays/news/2006/january/janenergy.htm ].

Thanks in advance,

   -Matt

[Titantornado]

Can't calculate that from the vids and pics, but there's a good chance this has already been done for you.  Try searching USGS for the streamflow for this river

[Nando]

Just for you to know what type of power you may harvest

8 feet = 2.4 meter

Power available 2.4 * 6 = 14.4 watts/liter of water volume.

So if you have, lets say 1587 gallon/minute = 100 liter/sec

the power will be 14.4 * 100 = 1440 watts

Therefore if you have 15870 gallon/minute = 1000 l/sec = 1 M^3/sec

The generated power = 14.4 KW

I wonder how much is the cost of producing 1 KWh of energy in your area ( hydro or thermal), I may presume around 0.03 cents.

so 14.4 kwh* 0.03 $/kwh = 0.432 dollars is the production cost each hour the hydro works generating 14.4 kw, for $3784 dollars production in one year.

Regards

Nando

[mattpower]

Titantornado & Nando -

Thanks very much for your responses. I was able to find this river in the USGS site (http://waterdata.usgs.gov/ct/nwis/uv?site_no=01209901 - Rippowam river). Great resource, thanks. It looks like this river has an 8 year mean flow of 34.4 cubic feet/sec... which looks about like the number you used, Nando.

Electric energy is extremely expensive here (just had a huge rate hike in January), and we are now paying retail $0.16/kwh, supposedly $0.126 for generation costs, $.034 for distribution costs. So it looks like each of these sites could generate about $15000 - $16000 worth of electicity per year..?

[Oso]

You are miss reading the data.

That average stream flow of 34 ft3/sec is for feb 12 only. That is each feb 12 for eight years.

You need to go back to the site and get the monthly stream flow data. When you get the table with eight years of monthly averages, you will find five months of the year, numbers are below 34. July and aug are the worst, at 13.4 ft3/sec.

You then need to talk to the agencies with jurisdiction over the river (particularly Fish and game) about flow restrictions. If they will not let you divert more than 50 percent of the flow, you might end up with 6.7 ft3/sec usable.

Oso

[keithturtle]

The amount of water energy available to you is miniscule by generation standards, from a utility's perspective.   There is enough, however, to set up a small scale "proof of concept" model for, say, hydrogen production.   East coast energy needs are real, and if someone would be willing to set up a plant that would produce H2 for fueling a city bus, for example (or maybe the police chief's car), you might be onto something.   There is enough flow for that.

Keith