Introducing Synthwave

Introducing Synthwave

Now that we’ve validated the core concept, it’s time to spin Synthwave into its own mission with the goal of building a real, working, electrochemical Direct Ocean Capture machine.

In addition to all of the normal mission functions (recruiting, organizing, publishing, etc.) it will need to tackle three core engineering areas.

Degassing + Measurement

The ability to efficiently degas the electrolyte is the biggest unknown right now. How can we degas a given volume? How do we measure what kind of gas is being removed, and how much? If we’re removing CO2, how do we store it?

Being efficient is key, as I suspect the vacuum pump will be our biggest energy draw. The electrolyte needs to be degassed twice, and I suspect the resulting CO2 will need to be compressed.

Cell Design

The next biggest unknown is the design of the cell itself. It’s going to be tricky: We know there need to be two cells with two sets of electrodes. There are multiple steps to the process: How do we manage the timing?

It should be possible to design a flow cell. This should be the goal, although there may need to be a few intermediate steps along the way. Figuring out the development roadmap should be one of the first things we tackle.

Cost Optimization

There are two aspects to cost optimization: The overall cost of the ‘developer kit’, and the technoeconomic efficiency of the cell itself. Both are important, but for different reasons. Keeping the cost of materials low is key for recruiting other hackers and collaborators. Ensuring the process is cost-competitive is key to actual widespread adoption.

Where to go from here?

Ideally, we can recruit volunteers to help us on the above problem areas. We should aim to break experiments into small pieces (for example, we don’t need the full Synthwave setup to test our ability to degas water and measure the output).

In order to continue forward momentum, I’ll aim for weekly updates on this forum. Should we have enough interest, we can pull in some other project planning tools, but for now I’d prefer to keep our software load to a minimum.

Please reply here or contact me on Discord if you’d like to contribute!

Here’s a (very) rough diagram of Synthwave 1.0. Adding it here for posterity. Don’t make fun :joy:

1 Like

The official List of Materials has been moved to the GitHub repo!

1 Like

Quick update from Synthwave HQ!

The prototype is coming along nicely, with only a few changes to the BOM so far.

I’ve posted the 3D Models and software to GitHub. I haven’t had time to write any documentation yet, but I’ll get to that once I create a page.

One loose end I probably won’t address until I build another one: How to secure all of these pumps and solenoids to the 3d printed shell.

The current design allows you to screw M2 screws directly into it. (I had to drill these out a tiny bit in order to get the screws to bite properly. But it works fine.)

I’d like to update the design to use theaded inserts. These are way more durable and user-friendly, but will require some trial and error to get right.

Two big updates!

First, the custom PCB is complete and has been ordered from OSHPark. It should be here in about 14 days.

Second, I’ve completed a minor redesign of the shell that improves durability while making it easier to mount components and route tubing. I’ll be printing this overnight with the goal of assembling the second prototype later in the week.

Finally, I decided that my idea to use threaded inserts wasn’t worth the added complexity. While it would certainly improve the toughness of the finished product, I’ve found that properly sized mounting holes work almost as well.

Just completed a round of updates to the 3D model. This version does a few things:

  • Adds a new partial-lid version that uses approximately 30% less filament and takes less time to print.
  • Makes the rear wall a bit more sleek and better sized to the new PCB
  • Adds a second hole to make the tubing easier to route. This also allows the containers to be filled from the bottom up, which hopefully reduces air bubbles.
  • Standardizes the screw holes at 1.9mm diameter. In my testing, I found that this offered the most consistent fit for M2 screws.
  • Rearranges the placement of the pumps and valves so that the entire apparatus can fit upside down into a 5 gallon bucket for easy storage.
  • Improves the fit and finish of the lid, and allows it to fit on either side for both storage and operation.
  • Add mounting holes for custom PCB (see previous post)
  • Add “synthwave” lettering for coolness purposes
  • Change release solenoid valves to 1/2" NPT fittings instead of 3/4"

Finally, I’ve decided not to use threaded inserts. While they’re great for certain things, they’re just way too fiddly for something that takes this long to print.