User:Vincecate/Pipe Spar

Looking at Red Hawk Spar and thinking about using standard pipes to make a spar. Could have 1 pipe or maybe a group of 3 or 7 pipes.

First lets look at a single 36 inch sched-40 stainless steel pipe. This is probably 0.375 inch thick (nearly 1 cm). The density of stainless steel is about 8000 Kg/m^3 or 8 grams/cc. At 36 inches diameter it is about 287 cm in circumference. If we have a pipe 150 meters long this is 8*287*150*100=34440000 grams or 34,440 Kg. Stainless costs around $5/Kg with a pipe being a bit more than this.

If we have 20 meters above water we have 130 meters underwater. Displacement for 3 foot diameter pipe is 1.5*1.5*3.141592 = 7.069 cubic-feet per foot of pipe. With 426.5 feet underwater and each cubic foot of water is 60 lbs, then 7.069 * 426.5 * 60 = 180,885 lbs or 82,048 Kg.

After taking out the weight of the pipe, we have 82,048-34,440= 47,608 Kg for ballast and living space. If we use half for ballast then we have 47,608/2 = 23,804 Kg for living space.

Could use a thicker pipe and still have interesting size living space. Can also brace the joint between the pipe and the living space. Lots of lift really.

The pipe is closed off with an air valve so we can use the pipe as a huge air tank for Compressed Air Energy Storage. Can use solar to power air pump. Generator runs on air pressure. Plenty of energy storage for a family. Some energy is lost making cold air, but we probably can use the cold air to cool the house instead of an air conditioner.

If there was rough weather coming might want to keep high pressure in the tank. The high pressure air can give the spar extra strength by keeping the pipe from ever buckling.

A computer will measure air going in and out of the tank and sound an alarm if the pressure is changing from what it should be. Would also want the computer to monitor the height of the house above the water and sound an alarm if it ever started going down.