We have become very skilled at making durable and cheap products. There are also some negative side effects. One of these is that our society produces large amounts of waste, which will remain in landfills for a very long time. The manufacturing of these goods can also be harmful to the environment. This includes raw materials, refining and supply chain. It is a terrible thought, and most people don’t think about it. It’s impossible to make everything eco-friendly, but it is possible to make some things eco-friendly. This includes a strict definition that considers the availability of raw materials, reusability, and eventual disposal.
Accenture Labs and the University of California, Berkeley have created a wireless heater that can heat anything placed inside. The heater can be placed on any standard wireless charging pad. The heater comprises paper, bits and shellfish, silver nanowires and leaf skeletons. It can heat a batch of cookies up to 70 degrees Celsius, but it will eventually degrade into compost within months.
We believe there is a space for “semipermanent” technological design. If we prioritize the decomposability and functionality of materials in our design, then can we design durable interfaces that have enhanced functionality and are easy to dispose of. –Katherine W. Song et al.
One quick note about “biodegradable” items: When applied to commercial products, the meanings of “biodegradable,” ‘compostable’ and other ecological buzzwords are not necessarily consistent. While some products may technically degrade in natural conditions, this process can occur under very specific conditions and might not be practical for all end users. For the Berkeley-Accenture project, the researchers use the terms “decomposable” and “backyard-degradable” to emphasize that this thing will turn into the dirt in a matter of months if you bury it in your yard.
The skeleton of the fig leaf is the framework for the heater. Because it has fine branches, the researchers chose this because it allows heat to be distributed over a large area. You can easily skeletonize leaves yourself, but you can also buy pre-processed versions on Amazon. The chitosan gel is used to coat each leaf skeleton. This is a polymer made from leftover shellfish pieces such as shrimp shells. The coating helps to keep the skeleton in place. Next, dip the leaf skeleton in silver nanowires. These are also available off-the-shelf. Next, attach a few leaves to a kraft paper bag using paper tape and wire them together using nontoxic, conductive, silver ink. The packaging is complete by drawing a silver antenna to allow the device to receive power wirelessly. As a temperature indicator, nontoxic thermochromic pigment is possible.
The copper coil in the video is not backyard-degradable. However, it is a substitute for a silver-ink-printed coil, an established technology that researchers were not focusing on for this project. Surprisingly, the leaf is what takes the longest time to decay, but it should be done in around a year.
This heating envelope can be used in many ways. Researchers were able to heat chocolate chip cookies and stroopwafels to the perfect consistency. If that’s not enough, they suggest that the heater can be used to heat milk or juice, activate shape-changing elements, warm-up wax strips and create customized protection for what is inside. These heaters could also be used with phones that have bidirectional charging.
You don’t have to worry if some of these applications seem wasteful. All of the materials are inexpensive, readily available and easy to assemble. They will also gently return to nature in just a few months. This requires changing how we think about waste and what it means to be wasteful. The heater shown here shows that you can prioritize natural and backyard-degradable materials and structures in designing and manufacturing at least some products. It also offers a unique application space and perhaps a new category of semipermanent electronics that we can reuse and recycle guilt-free.