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Hurricane Awesomeness - HA Generator

by admin on Fri, 2014-01-17 00:32

Activity: Presentation

Scout Levelcc: All

During one of our meetings Mrs. Caroline brought out a little toy model of a monster truck that was powered by salt water and, we were fascinated by it so we wanted to do something that was powered by salt water. This little truck ran using a very small amount of salt water and would last about 4 hours.

The next meeting we talked about what would happen during or after hurricanes if they occurred here in Titusville Florida (Our study location).  One thing that we discussed was that people would not have power and they would need a generator to power their lights, refrigerators and other items in the house or business. We then went to work deciding on how to create electricity. After much discussion we wanted to create power in the same manner as the little truck and came up with the “H.A. Generator” project.  

The basic engineering for our generator is that we are using Copper, Aluminum, and Salt to create the generator. The electrical science behind our project is that an electrochemical reaction occurs when these three items are placed together. Electrochemistry deals with the links between chemical reactions and generation of the potential electricity (i.e. a battery that generates its own power). This includes the study of chemical changes caused by the passage of an electric current across a medium, as well as the production of electric energy by chemical reactions. Electrochemistry also embraces the study of electrolyte solutions and the chemical equilibria that occur in them. Potential energy is created when the negative ion of the salt and copper plate collects on the aluminum plate. We purchased the metals and tested the initial theory using a bucket, salt water and a meter to verify that our project would work.

At our next meeting, our engineer Mr. Louis showed us a scale model of our “first generation” salt water generator on his computer. Then we started to build a prototype of our H.A. Generator. We split up into two groups where one group programed and one group was in the workshop with adult supervision. In the workshop, we started on the model by cutting wood and when we were done cutting slits in two blocks of wood. Then we had a skinny rectangular block of wood that we screwed together on the side with one of the blocks of wood with slits in it at the top and the other at the bottom. Then we put copper and aluminum in a pattern that was copper then aluminum and so on in the slits on the wood.

We also learned about and used the following tools: 1) Radial Arm Saw; 2) Laser Alignment Tool 3) Drill Press 4) Screwdrivers and 5) Volt Meter. Later on, we had help from supervisor and made the real “H.A. Generator”.

Our initial generator was in the bucket container and had 6 sets of alternating copper and aluminum plates. This configuration of plates where connected in series and created enough amps but not enough volts because all the plates were in the same container canceling out the building of volts across plate pairs.

The basic engineering for our generator is that we are using Copper, Aluminum, and saltwater to create the generator.  The electrical science behind our project is that an electrochemical reaction occurs when these three items are placed together.  Electrochemistry deals with the links between chemical reactions and generation of the potential electricity (i.e. a battery that generates it’s own power).  This includes the study of chemical changes caused by the passage of an electric current across a medium, as well as the production of electric energy by chemical reactions.  Electrochemistry also embraces the study of electrolyte solutions and the chemical equilibria that occur in them.  Potential energy is created when the negative ion of the salt and copper plate collects on the aluminum plate.

 

Time

Across 1 plate pair

Across 1/2 plate pair

Across all plate pairs

Start

449

900

1179

2 hours later

417

630

690

2.75 hours later

443

520

539

 

Values are in millivolts

By experimenting with plates in two different buckets we found an increase in volts.  That is when we determined that we needed to have the plate pairs separated so that we can increase the volts so that we can have enough energy to power something.

With the help of our engineer the “second generation” salt water generator container was redesigned to have 8 separate cells. We again connected the plate pairs in series (It’s like stacking batteries on top of each other) which provides more volts opposed to connecting the plate pairs in parallel which provides more amps.  Following is a chart showing volts being generated by the “H.A. Generator”:

We are currently using a volt meter to determine how much power is being generated. Discussions with our engineer it was determined that we should have generated enough power to light a small motor which is three times more than our current values.

We went back to putting the plate pairs in separate containers and the voltage doubled as expected. It was determined that each cell in the generator had to be isolated or not sharing water, since the water is the carrier of the negative ions. So we need to work on the container more insuring that the generator cells are truly isolated.

We went back and isolated all the cells and the voltage across on cell is now .41 volts under a load and the entire battery has enough volts to power a led light or a buzzer. The battery can sustain it’s voltage if we keep the saltwater circulating providing a water flow for the negative ion to be transported. We added an air pump to provide this function. The power at a minimum level lasted 24hour before needing to change the saltwater.

 

Here we are learning and sharing with each other.

Let us know what you think