Flying Only with the Heat of the Sun

If you picture a flying machine, you probably imagine a craft which is heavier than air, somehow kept aloft with wings or propellers. Heavier-than-air flight dominates discourses about aviation. “Sustainable” crafts are designed to be as light as possible (whilst remaining heavier than air), so that they require less energy from whatever renewable source they use for lift. These machines include human-powered planes such as those using pedals to rotate a propeller. Lighter still are kites and gliders, which remain heavier than air, but rely on air resistance and lighter air around them to fly.

Less discussed are flying machines which are lighter than the air they fly through because the weight of their materials and passengers is counterbalanced by the hot air or light gases they contain. [1] Perhaps this is because most of us experience flight in passenger airliners, not Zeppelins. In theory, making lighter-than-air flight sustainable is simple: heat a container full of air with sunlight so that it rises. In January 2020, Leticia Noemi Marqués flew freely in the Aerocene Pacha solar balloon, the first Fédération Aéronautique Internationale certified fully-solar, untethered, manned flight. Previous flights of this kind went uncertified or relied on propane burners or inflation generators [2]. Aerocene Pacha flies on solar energy not from solar panels or batteries but absorbed directly in the envelope (the fabric of the balloon). [Read more…]

Remaking Suburbia

Quoted from: Trainer, Ted. “Remaking settlements for sustainability: the Simpler Way.” Journal of Political Ecology 26.1 (2019): 202-223.

In view of the global resource and ecological situation, per-capita resource consumption rates in the rich world probably need to be reduced by 90%. This can only be done if there is a “de-growth” transition to some kind of Simpler Way centered on mostly small, highly self-sufficient and self-governing communities in control of local economies within a culture that is not focused on material wealth.

It is not surprising that the viability of such a vision is typically regarded as implausible. The aim of this study is to show that normal outer city suburbs could be restructured along the lines required to cut global impacts by the necessary amount, while improving the quality of life. Data on typical Australian consumption rates, food production yields, suburban geographies, etc. is used to estimate the achievable reductions.

The theoretical conclusion that such reductions could be made aligns with a study of the Dancing Rabbit Eco-village in northeast Missouri. Heavy cuts in resource consumption cannot be made without extreme change in economic, political, settlement and cultural systems.

The Chukudu is a cargo scooter built entirely from wood

Image: Lahminewski Lab, CC BY-SA 4.0.

From the Wikipedia page, which summarizes and links to all sources that are available online:

The chukudu is a two-wheeled handmade vehicle used in the east of the Democratic Republic of Congo. It is made of wood, and is used for transporting cargo. The chukudu generally has an angular frame, two small wheels (often of wood, sometimes wrapped with rubber), handlebars, and a pad for the operator to place their knee on while propelling the vehicle with their leg. On a descent, the rider stands on the deck like a kick scooter. On flat ground, the rider can put one knee on the deck and push the ground by the other foot like a knee scooter. Rubber mud flaps and shock absorber springs may be added.

In Goma, where chukudus form the “backbone of the local transportation system”, chukudus are made of hard mumba wood and eucalyptus wood, with scrap tires for wheel treads. These chukudus take one to three days to build, and last two to three years. The most commonly used size is about six and one half feet long, and carries a load of 1000 lbs. However, the largest chukudus can carry up to 800 kilograms of weight.

A small chukudu can be built in about three hours, using dimensional lumber and materials available in a hardware store. The chukudu is customizable to carry different types of cargo. To haul firewood some chukudus have a hole drilled in the middle of the sitting deck, and the operator can insert a stick to hold firewood in place. Others have a large basket to carry various loads.

Chukudus image colection.


Thanks to Spencer Cappallo.

The Sailboat as a Research Lab for Resilience and Self-Reliance

The hundred rabbits research lab does experiments on resilience and self-reliance through low-tech solutions. The two-headed team practice what they preach: the lab is located on a small sailboat that has been traveling across the oceans since 2016. Among other things, their website contains a lot of practical information for those who want to go off-the-grid, whether it is on land or on water. Because they run a design studio and create free and open source software, there’s also sound advice on how to work off-the-grid efficiently.

Inventor harvests methane gas from ditches and ponds to power his moped

Shallow ponds and ditches are producers of greenhouse gases, especially methane, which is released by the breakdown or decay of organic material. Gijs Schalkx harvests this methane from ponds — by hand — and uses it to power his moped. Eight hours of hoeing in a ditch supplies him with enough fuel to ride his vehicle for 20 km. He calls it “a quest on keeping the combustion engine alive in a fossil free future”. [Read more…]

Low Tech Webring Directory

The Low Tech Webring Directory is for homepages of people who are interested in low tech, small game tools, and other forms of Web 1.0 inspired creativity.