Posted by Jeff Id on May 12, 2010
I really enjoy Willis Eschenbach’s posts on WUWT. He’s a good writer and makes reading fun. Today he’s put one up on the super cloud maker ships which launch water into the air to increase cloud cover and save us all from global warming doom.
Bill Gates invested in the project apparently, but Willis found some of the basic numbers to do some calculation on the invention.
The ship launches 10 tons of water per second to 3000 ft altitude.
The machines, developed by a San Francisco-based research group called Silver Lining, turn seawater into tiny particles that can be shot up over 3,000 feet in the air. The particles increase the density of clouds by increasing the amount of nuclei contained within. Silver Lining’s floating machines can suck up ten tons of water per second.
Willis did a quick calculation for how much power it would take to launch the wter at 100 psi.
Next, how much fuel will this use? The basic equation for pumps is:
Water flow (in liters per second) = 5.43 x pump power (kilowatts) / pressure (bars)
So to pump 10,000 litres per second (neglecting efficiency losses) with a pressure of 3 bars (100 psi) will require about 5,500 kilowatts.
Willis’s calculation is off by a bit. I don’t know about you but my 100 psi garden hose has difficulty launching water much over 20 ft, can you imagine the fun your kids would have in the yard if you could spray up to 3000 ft??
Just for fun, I ran the wattage required to lift 10 tons to 3000 ft every second.
power = (weight * height)/second
= (20,000lb *4.448 N / lb)(3000ft*.3048m/ft)/1 second
= 81,345,000 = 81 million watts (MW)
If you start looking at engine and pump efficiency, you can multiply this number by 4 or more times. Let’s say they got everything right though and you only loose half due to efficiency and need 160 MW per ship to launch the water.
It would require about 200,000 horsepower of engine and pump.
Actually the engine efficiency is said to be 50% at the highest settings. So, if we take my above calculations and look at pump losses, energy for vaporization and running the engines at less than full power, 6 of these engines is probably a more accurate calculation.