Why and How to Build a Fiber Foamie

During covid, I built a fully solar-powered off-grid micro-camper called a squaredrop. I designed it to tow behind my Honda Civic. I traveled over 22,000 miles to 35 national parks in 28 states. You can see the whole adventure at movingcabin.com.

What’s a Squaredrop?

A squaredrop is sort of like a teardrop trailer but more square. This means more room inside as well as more room outside for solar panels. The impact on towing efficiency is very small as long as the camper is not wider or taller than the tow vehicle.

I did design my camper to charge an electric vehicle, the Sondors Metacycle which I originally intended to buy. But a lot happened at home and I decided to postpone the rest of the national parks until after grad school and spend some time with my family.

Moving On Up

Since then, I traded in my Honda Civic and bought an electric car (The Chevy Bolt) which can tow and has great range!

@cjtrowbridgeI got a solar powered electric vehicle! ⚡♬ original sound – CJ Trowbridge

What’s Wrong With The First One?

My first-gen squaredrop camper is great but not perfect. It’s very overengineered. I built it to be extremely durable. It is made of 3/4 inch pressure treated plywood over a 2×6 deckboard frame and insulated with one inch polyisocyanurate foam, and then it’s painted with white flex seal.  On top of that, every joint is steel bracketed. So it’s fire proof, water proof, and it would probably survive a highway-speed rollover. But it’s also very heavy and too maximalistic.

So I decided to build something extremely light and extremely minimal that can still charge an electric vehicle. Another thing I wanted to improve on was the hubs and tires. The first-gen squaredrop has a top speed of 60mph which is super not ideal for transcontinental jaunts.

What’s A Foamie?

A foamie is a camper that’s built from foam instead of wood, and then it’s wrapped in something like fiberglass or more often “poor man’s fiberglass.” The construction technique is called composite core construction.

Here’s a really good and comprehensive explanation of the composite core construction technique…

Basically if you take a foam structure and wrap it in something stronger like fiberglass, then the whole structure acts like a solid piece of fiberglass. It’s a super cheap and very strong construction technique.

A foamie is just a camper that is made from this technique. Here’s an example timelapse of the construction process for a foamie…

What To Wrap It With?

The most popular way to wrap a foamie is with what’s called “poor man’s fiberglass.” This is what’s demonstrated in the video just above. Basically you wrap the foamie in canvas that’s been saturated in wood glue. Once it dries, it’s extremely strong. And then you can simply paint over it and you have a good looking and highly durable foamie camper.

I want to use carbon fiber instead. This is much lighter, much stronger, and much sexier. The technique is very similar, and the composite core construction video above explains the technique and best practices for doing something like carbon fiber or even fiberglass instead of the “poor man’s fiberglass.”

Design Inspirations

I almost feel like this motorcycle camper trailer is too big.


This is actually a carbon fiber teardrop, and it’s cute but the pure teardrop shape is boring because you can’t really put solar on it. Also the dark color means it will be extremely hot inside all the time.


I really like the angles on this one, and the styling on the side with the panels. I think this would be a good general aesthetic, but again the dark color means it will always be hot inside. And instead of a roof rack, I would put as much solar as I can fit.


This is basically perfect except it needs solar, and I’d definitely paint the ugly red trailer.  Also, it looks a little tall. I happen to know that this trailer frame is the 4×8 harbor freight frame. It looks like the trailer is five feet tall or more. I would want it to be a little shorter so that it is more efficient to tow.


This is a project I volunteered on earlier this year. I really like the way the structure is not tall enough to stand up in; the design forces you to spend at least some time outside, but provides shelter when it’s necessary.


On that note, I am interested in designing something similar to a single cell from a capsule hotel. It should have a bed, some basic lights, HVAC, and that’s basically it. I don’t need the full kitchen which I included in the first generation but almost never really used. The car has lots of space in the back for my bear-proof cooler if I feel the need to bring cold things.

Closed Loop Water System with Integrated Biogas Capture

I propose to build a simple proof of concept system which simultaneously solves many problems associated with water use sustainability.

Key Problems With Current Strategies

Essentially all municipal sewage systems around the world are still using the prehistoric systems pioneered in the indus valley civilization over 6,000 years ago.

We take fresh water, use and pollute it in our homes, then dump it into the sewer. Once in the sewer, municipalities dilute the sewage, sterilize it, and then dump it into the rivers and the ocean. This pollutes the rivers and ocean, wastes valuable organic solids, and drains our limited sources for fresh water.

There is a better way, and it’s far less complicated. If we are going to take water from aquifers, then it should go back to the aquifers rather than being dumped into the rivers or oceans.

Uses of Water

The first step in a more sustainable alternative system is a well which draws water up from the aquifer. That water is then filtered and used for three initial purposes:

    • Drinking
    • Bathing
    • Washing Hands

The water that does down the drains in sinks and showers is routed to a gray water holding tank where it is reused for flushing toilets. Overflow from the gray water tank simply flows into the digester.


Effluent flows into the biogas digester. Effluent includes all sewage from toilets and waterless urinals as well as household compost and any overflow from the gray water holding tank.

Quick Note On Bacteria: There are two kinds of bacteria, aerobic and anaerobic. All bacteria can survive only with or without oxygen. Aerobic bacteria can only survive with oxygen. Anaerobic bacteria can only survive without oxygen. The way cities sterilize sewage today is to simply deprive it of oxygen for a while, and then give it a lot of oxygen for a while. No bacteria can survive both stages of this process, so the sewage becomes completely sterilized.


Quick Note on Biogas: Biogas is methane, the same thing as natural gas. It can be used for anything natural gas can be used for: cooking, heating, generating electricity, etc.

A biogas digester is basically just an airtight anaerobic holding tank which uses bacteria to break down organic substances from compost or sewage and then it captures and store the biogas produced by this process. When sewage is deprived of oxygen, the anaerobic bacteria thrive, producing methane or biogas. Once they have eaten up all the organic material they can, they wait for more to enter the tank, and then begin producing biogas once again.

Some digesters will use something like a garbage disposal to help chew up the solid materials coming into the tank, accelerating the process of breaking it down for digestion.

Biogas is the most significant greenhouse gas contributing to climate change. It is 100x worse than carbon dioxide, so capturing it for use as fuel means reducing by 99% the impact of simply letting this gas escape into the atmosphere. Currently our municipal sewage processing systems simply pipe all that biogas out into the atmosphere, wasting an incredible amount of valuable biogas.

Effluent Filtration

Now that the system has digested the sewage, it can flow out through a multistage filtration process. The first step in filtration is to separate the liquids from the solids. The second step is to sterilize both the liquids and the solids the same way every municipal sewage system in the world does, through alternating aerobic/anaerobic processes which kill all the bacteria. Since we have already processed the sewage in a biogas digester, the anaerobic stage of sterilization is already done. We simply need to pump oxygen into the sludge coming out of the digester in order to completely sterilize it. For good measure, we can also pass it through an ultraviolet filter to add a layer of redundancy to the sterilization process.

Return To Sender

Now the sterilized liquid can be routed into a bioswale. This is similar to a septic system but far superior for several key reasons. Because a bioswale does not need to manage solid waste, it does not “get full” and therefore requires no regular maintenance. It captures any heavy metals using bioremediation techniques, and uses sunlight to denature any remaining complex organic molecules like drugs and hormones. The remaining pure water seeps down into the aquifer (a sufficient distance from the well), replenishing what we took from the aquifer.

Closed Loop

This system is a closed loop, meaning that it does not take water from the aquifer and dump it into the rivers and ocean. Instead it purifies that water  and returns it to the source. This means the system will keep working indefinitely in contrast to current municipal systems which simply destroy each source of water before moving on to find a new source to destroy.


The other huge benefit of this system is that the biogas being produced in the digester can be used to heat the water for hand washing and showers as well as powering cooking stoves and electric power generators.

One person’s sewage produces two hours of cooking biogas per day. A community using a system such as I have outlined here produces far more power than they need. In fact there are examples of farms that use biogas digesters to power all their buildings, equipment, and vehicles. The amount of biogas energy being wasted by current techniques is enormous.

Black Gold

We talked earlier about the solid wastes being extracted from the liquids flowing out of the digester. These solids are commonly composted with wood chips. This process takes a long time, a year or more. The solids are simply deposited in a holding pile along with wood chips, then they compost just like humanure or other composting toilet technologies.

After they are done composting, that literal sewage is converted to valuable mineral-rich soil ready to be used to grow food. This process can leverage the urban process to accelerate efforts like reforestation, or even the conversion of deserts into farmland and gardens. Everywhere there are people using toilets, the surrounding land could easily be made fertile using this method.

A Tighter Loop

Because this proposal relies on the use of aquifers as storage facilities where wells and bioswales draw and deposit fresh water, it relies on the assumption that you have an aquifer to leverage. This is not actually necessary in all cases. You could simply use additional stages of filtration such as distillation and/or bioreactors to purify the water sufficiently that it can immediately be reused rather than being dumped back into the aquifer. This more radical solution would be appropriate for extreme desert climates where the “yuck factor” is outweighed by basic survival needs.

For now, the aquifer replenishment method seems the easier sell!

OurSpace: Distributed Serverless Anti-Hierarchical Social Media

The main idea is to use something like IPFS to establish a distributed non-hierarchical alternative to both the web and the incumbent social media institutions while also creating a resilient alternative which would form a thick protocol on top of which people can then construct and extend interfaces like apps or websites.

Imagine I have an RSS or JSON file representing my personal feed of social posts (text, images, video, audio, etc.) This is served over IPFS and/or other similar protocols such as GitTorrent, Tor, or simple HTTP.

Ideally, there would be a simple process for connecting a person’s persistent identity to a standard way of accessing their feed file via whatever means. So for example, I could use my Ethereum wallet address like a username (People already do this using QR Codes on Snapchat), and then people could automatically look up how to find my feed file via whatever network and protocol they are using. A simple DHT could link my public wallet address to the IPFS address for my feed file, and the GitTorrent address, the HTTP address, and/or a Tor address. So that everything works regardless of what network you are using.

I especially like the idea of using an Ethereum wallet address as a username because it would mean that authentication via metamask or something like that would already be a simple process which is widely adopted plus already being based on a strong distributed system. It would also make it easy to send money to people. Many activist content creators use their whole bio section to post their venmo, cash app, paypal, etc. This would greatly simplify that process.

For synchronous communication, there are already protocols like Tox which facilitate entirely distributed, serverless, end-to-end-encrypted direct messaging as well as voice and video calling.

It’s easy to see how this concept could supplant tools like facebook, twitter, whatsapp, etc. It would be objectively better from basically every perspective, plus it would mean people can easily write their own clients featuring whatever kind of aggregation, curation, etc they prefer. It could easily be extended to focus on extreme security and anonymity or as a  very public and resilient content management system for a blog. There are so many directions and so much potential!

Existing Examples and Case Studies

Here is an example of a very similar approach to implementing a podcast player;



The Hard Part

It’s very easy to publish data on IPFS or bittorrent or whatever. You get a unique hash which anyone can use to access what you have published. So Maybe you publish the index file for a website and then inside the file it links to all the other resources which you have also published.

(This all already works. See the example linked above.)

The hard part is revisions. If you change anything, then your original hash doesn’t work for the new revision and so you need a way to connect users to the current hash in order for them to find your current content.

I have thought a lot about this over the last few months and I have read extensively about the theory around the different ideas people have come up with to solve this problem.

GitTorrent is already a good solution to versioning but it still requires DNS as far as I can tell from reading the documentation. DNS is a hierarchical and fragile and high-latency system so that’s not a good fit for this.

DHT means distributed hash table. This is a distributed KVS or key/value store so you put some data and you get a hash which you can share and that will let people find the data. This is what a magnet links to. The data that the magnet’s hash points to in the DHT KVS is the list of hashes for the pieces of the torrent which you can then find from peers and assemble into whatever you’re trying to download.

This DHT KVS paradigm is very close to a good match, but there are still several problems to address.

Quick aside; one of the main fundamental arguments I wanted to make with this project is that is should always be trivially easy to send money to any user. Lots of people put their venmo/cashapp/paypal/etc on their bio on social media. I want that to be built into this project. So it would be really exciting to use an ethereum wallet public address as the central identifier of each user. This also has the benefit that a wide range of production-quality cryptography tools already exists around ethereum wallets. For example, metamask can easily sign things for you using your wallet. (Signing examples)

Okay so imagine this; a distributed hash table which has no unique primary key and has four columns:

  • First the primary key is the ethereum wallet public address for the users.
  • The second column is the publication timestamp for the main index or rss file or whatever their main file is.
  • Third, the current IPFS hash of their main file so that everyone can find it.
  • Last, it stores an ethereum signature to prove that the IPFS hash and publication timestamp belong to the ethereum wallet public address listed.

This means anyone can quickly and easily update their content and publish with extremely low latency to the entire fully-distributed network.

Following a given user (like we do on facebook or twitter) means your own app is going to automatically download and mirror their content (just like a podcast app would) and this means others can access that content from you, so the more followers you have the more easily accessible your content becomes.

What’s in a main file?

I really like the idea of using RSS with XSLT or something like it to serve a simple rss file that could also be styled as a webpage or blog. But really this file could be anything.

Meta tags in the file can link to things like the list of accounts you’re following, your secure protonmail address, your Tox address so that people can send you secure instant text, voice, and video calls. These could also all be hashed so that it’s possible to search for all the people whose email or phone number you have without them having to expose their phone numbers or emails to the network.

Then of course there is the social content you wish to publish in your feed.

All of these things can be integrated into apps so that users can seamlessly browse a list of popular or suggested mutual friends based on observable connections and then find accounts to follow.

Security and Privacy

IPFS is not secure. Anyone with the hash can download the file, just like with torrents. So it makes sense to include an option for end-to-end encryption for those who want to have their content be visible only to friends.

Simpler Usernames

It’s easy to imagine using domain names as a way to link to ethereum wallet public addresses. It could be as simple as having those addresses linked on the website or it could be a DNS text entry or some other kind of DNS record.

This would mean you are not reliant at all on DNS except as an optional shortcut to allow people to find your address without sharing the QR code or text address.

DIY Biogas Digester Research

Small biodigester build video


IBC Tote based digester design

  • Using a garbage disposal as an input grinder
  • Algae mitigation
  • Tank insulation


Larger build

  • hydrogen sulfide filter to clean the methane
  • flashback arrestor
  • methane storage with inverted barrel in water for pressure and isolation.

Community-Scale Biogas Digester

Includes condenser (yellow) which removes evaporated water from biogas.

California Farm Case Study

At 40 minutes in if farmer talks about how the biogas collected from cow manure is enough to power the farm and all the vehicles



Compressing Biogas for use as CNG Alternative