Peter Coyle

I had a great chat with the Power Tree’s inventor, Honey – she had made a model of the tree, and we talked about how she came up with her idea.  I shared how I planned to make her idea real, and everyone involved in the video call was excited to see how it comes together!

So.. over to me to make it happen.

I’ve had a busy 2 weeks bringing together all the different bits I’ve been working on.  I’ve been sanding and spraying solar panel mounts.  Gluing wires into them.  Solder wires for solar panels.  Thermoforming branches.  Twisting metal wires to give the branches strength.  Designing, cutting, masking, and spraying a plastic cover for the generator.  Figuring out and wiring the generator.  Designing, 3D printing, and spraying a collar for the bottom of the tree.  Putting it all together!

There was so much more than I expected, but it was fun to work on, and... it works!

Recently, I’ve been looking at the power tree’s generator and its’ leaves!

Generator  -

The generator will show how much power the tree is making and convert it into something that we can use to power other things!

To show how much power is being created, I’ve included several meters that measure voltage and amps.  These are two of the main ways of measuring electricity, and if you multiply them together you get watts a measurement of power (and light bulbs).  This means we can use the meters to tell how powerful the power tree is!

I’m going to use lots of solar panels on the power tree so I’m including a clever little circuit called a “buck/boost convertor”.  The buck/boost convertor will take all the power coming from the solar panels and create a consistent output.  Exactly what I need to power things!

To show the power tree working I’m including a small fan that will come on when the power tree is in the sun!

Leaves -

I’m using 3D printing to create the solar panel leaves.    

Each leaf will be joined to the tree by a stiff wire that runs down each branch.  This means each branch and solar panel can be repositioned to best catch the sun.  This type of metal wire structure is often used by animators for their models so they can create stop motion animation - they call them armatures.  

The leaves themselves will be printed at Octo Design (where I work).  We have a 3D printer, that we use for prototyping our designs before they are manufactured.  Our printer creates 3D models by melting a liquid with a laser!  It creates the model in slices, one on top of the other.   Once the print is complete, it needs treating with heat and UV light before it can be used. 

I created several designs for the leaves on the computer, before printing a prototype of my favourite.   I was happy with the results, so I’m now printing all the leaves I need for the power tree.  Once these are printed, I should have all the parts I need to make the power tree!!

I’ve recently been looking at branches and solar panels for the power tree!

Branches – 

After a little experimenting, I found I could make tubes for the branches by thermoforming sheet plastic. 

Thermoforming, is where you heat plastic to make it bendy and hold it in a new shape.  When it cools it stays in the new shape!

To make branches, I needed to find just the right thickness of material – thick enough that it will be strong, but thin enough that I can roll it into tubes.  I found rolling the tubes like they roll paper straws made them very strong.

Next, I have to decide how to best join the branches!

Solar Panels – 

I want the power tree to generate a useful amount of energy – so I’ve found small solar panels I can use for the leaves.  To help me choose the right solar panels, I worked out how much power each one would give, and how many solar panels I thought the tree should have. 

I bought some panels to test and found that the amount of power the supply varies a lot depending on the time of the day, and how bright it is.  I, therefore, decided I need what is called a “buck/boost convertor”.  This takes a varying power source, and creates a constant voltage – this can then be used to power things.

Next I will have to decide what to connect to our power tree!  I could possibly add a battery, so we can store the power when it is sunny, and use it across the whole day.