Makeshift Wave Powered Cooling Mat

Visiting the beach with friends is lots of fun! swimming, surfing, sunbathing, etc...

However, there's one key element about going to the beach on a hot day with friends that is crucial: Staying cool in the hot sun. Now, if you are someone who is hooked up to non-waterproof medical equipment or bodily ports such as an IV PICC-line, or bandages that can't get wet, then the whole concept of even visiting the beach with friends quickly becomes a choice between staying cool and wet then getting medical complications, or staying home, or enduring the blazing sun.

Of course, it is possible to to dip one's legs in a pool with being submerged too far or sit on a cold damp towel to stay cool, but that is more difficult in a lake or ocean environment with splashing waves.

I say this from personal past experience with a port! Unless you are blessed enough to have a medical helper who is very skilled at waterproofing and sterilizing bandages, it is a challenge!

That is why I wrote this instructable; to show and help others build a makeshift wave powered hydrothermal cooling system for staying cool in the hot beach without getting wet.

I think people who lay in the hot sun while tanning would appreciate this cooling mat invention as well.

How does it work?

The waves move the handle of a water pump which pumps cool water to a heat exchanger underneath your beach towel, chair, or mat where you lay. The hose stays insulated because it is buried a few inches below the surface of the beach. You stay dry though! The water then gets pumped back into the ocean.

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• Beach Towel, Mat, or something thin to sit or lay on and have the sealed heat exchanger coil run underneath.
• Dual Action Pump or Bilge Pump- This kind pumps on both the up and down motions.
• Hose or Tubing at least 25 feet (about 7.5 meters) long - You could use a expandable garden hose, or really any fairly wide hardware store hose. Bury it under the sand to stay somewhat insulated.
• Hot glue sticks
• Hot glue gun
• Something that floats and cannot capsize - inflatable floating toy, empty PET bottle, or styrofoam block
• Two Somethings that sinks as an anchor weight - rocks, bricks, sinkers, anything that is heavy and sinks to the bottom soundly. the second sinker will be attached to the float and just helps it work on the down stroke.
• Zip Ties

Use some zip ties to fasten a weight to each end of the pump. You may only need one weight as an anchor.

Zip tie your float to the end of the pump opposite to the anchor weight. If your float is inflatable, inflate it, then just tie the zip through the inflatable's cap loop.

Preheat the glue gun.

Then, stuff the end of the hose part way into the pump hose and glue it in place. Fill in the excess space with hot glue till it is thoroughly sealed while still letting water flow through the center.

You might want to test for leaks before heading to the beach using a bucket of water!

Wind the hose about 3/4 down in a zig-zag pattern or spiral pattern. Lay your mat on top of that, then take the remaining short end of the hose so it drains away a short distance from the water.

Toss the pump rig out at the depth where the anchor weight touches the bottom, but the float can still ride the waves.

Bury the rest of the hose barely under the sand as a short of insulator.

The winding hose under the towel or mat is flowing with moving water from the lake or ocean which acts as a heat exchanger with your body.

It should start pumping water up under the mat and back away without getting you wet!

If you have followed all the steps then congratulations! You have made your own wave powered cooling mat!

Unfortunately due to unforeseen events it looks like I will not be able to travel a wavy ocean or lake this summer, and so I have not tested my device in a very wavy environment yet. It has only been tested in a tub.

If you've made one or have made a remix of it, or even if you need any troubleshooting, please test it out show us in the comments below!

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I hope y'all enjoy the rest of your summer!