Hydropower 101

You are at the top of the Empire State Building in New York City. You are at the very top where no one is allowed to go (except maybe King Kong) - 1,250 feet above the street!

And you drop a bucket of water and let it fall to the street. Say the bucket is enclosed so none of the water spills out. And say that fortunately there are no people on the street.

It hits the street level– with a crash you could hear blocks away! Might even go through the sidewalk, from 1,250 feet!

Now picture Niagara Falls – it’s only 176 feet tall.

But instead of a bucket of water, 150,000 gallons of water flow over the falls every second! It’s clear that it’s not so much the height of the falls that counts as how wide they are to permit the largest volume of flow.

There are a number of waterfalls in the continental U.S. that are a great deal taller than Niagara. And in Hawaii there are a number of falls taller than 2,000 feet. Too bad Hawaii is 1,625 miles from the mainland.

As we might expect most tall waterfalls in the U.S. can be found in the west. Washington has 28 falls from 600 to 2,500 feet tall. California has 22 and Montana has 17. How many of these can claim major electricity production – hydropower?

Not many and we can see why by looking at a few of the tallest:

- Colonial Creek Falls in Washington is 2,584 feet tall with average width of 50 feet!

- Avalanche Basic Falls in Montana is 2,320 feet tall with tallest single drop of 1,000 feet and here again, only 50 feet wide.

- Sulphide Creek Falls in Washington is 2,182 feet tall in an incredibly beautiful and inaccessible area with yet another 50 or so foot width.

These are just a few of many such powerful and beautiful water panoramas that are wonderful to see but impractical or impossible to harness for hydropower production.

All the same, there are hydropower plants all around the country. There is at least one in every state including Alaska:

Washington has 34; Tennessee 19; Oregon has 18; Idaho – 16 and California 12.
However, most of these use man-made dams and we will discuss the various components of water based electricity production in Hydropower 102 to follow.