Sustainable and clean cooking energy

I am researching the topic of clean cooking fuel, and some of my topics of interest include solar ovens and biochar. Does anyone here have any experience with working with those methods, or knows somebody who does? I am looking at this through a lens of affordability, ideally being able to make my prototypes(such as a DIY solar oven, or a biochar press) with household/easily accessible objects.

Hi John,

Welcome to Permies.

I suspect much will depend upon where you live.   For example, I have a solar over, but I live in an area where the skies are frequently overcast.  We also have around 46 inches of rain each year. While the oven sees use, it’s needs to be used in combination with other options.

Welcome to the forum.

The folks at Wheaton Labs have been working with solar cooking and cooking on RMH (Rocket Mass Heaters), Rocket Stoves, and other forms of cooking.

I thought there might be some video on the subject though I am not finding them.

I would love to have the Walker Oven:

https://permies.com/t/55253/Walker-Wood-Fired-Masonry-Cookstove

Here are some threads you might find interesting:

https://permies.com/t/205298/Solar-cooking-woes-solar-cooking

https://permies.com/t/166800/rocket-ovens/Brick-Outdoor-Kitchen#1309344

https://permies.com/wiki/106011/pep-food-prep-preservation/Cook-Grain-Solar-Oven-PEP

https://permies.com/wiki/106017/pep-food-prep-preservation/Cook-Grain-Rocket-Stove-Haybox

I hope some of the folks that are using there for cooking will reply and give their thoughts.

I love this solar oven. It will cook a roast in about 3 hours in the sun in South Louisiana. Great to have when a hurricane hits and all utilities are out!

Search on AMAZON - SOL COOK All Season Solar Cooker (17) Camper

Call Sign "Boogaloo"

Welcome to Permies Wayne!

I haven't tried a solar cooker before but having some kind of backup in case of extended times of utility interruption is something I really need to work on.

Now the wheels are turning in my head!

Check out haybox thermal cookers too. You need a heat source to bring things up to temperature, but once the pot is in the haybox, they stay cooking away for hours if necessary.

I'm quite a convert!

John Hunter wrote:I am researching the topic of clean cooking fuel, ... biochar.

This was something that confused me a lot when I was first researching biochar. Biochar is specifically charred wood where as much of the volatile material has been burned off, leaving almost pure carbon. This is great for the soil, but not what I would want to cook food on.

However, the goal when making natural wood charcoal, is to burn off the elements that create smoke, but retain the volatile material to later use for cooking. It is two steps, and is particularly important for people cooking indoors over an open flame, as it will reduce the smoke which damages peoples eyes and lungs, but be aware that it still creates carbon monoxide and can kill if the area is not well ventilated.

I would absolutely research rocket cook stoves. The types that Wheaton Labs have been experimenting with are properly vented outdoors, so the CO danger is minimized. Some are much simpler and intended for outdoor use, but they're a great place to start the learning process. Rocket stoves use regular wood for cooking, but are much more efficient than an open fire.

I'm a fan of top lit up draft(TLUD) stoves.
These stoves use fuel proccessed to peices of roughly the same size, turning it into charcoal in the process.
My favorite implementation of these stoves is shown here:

https://permies.com/t/170631/Indoor-biochar-producing-TLUD-gasifier

In this design,exhaust gasses are directed out of the building after heating the cooktop.

Martijn's creations are very accessible, and his YouTube channel is good.

The need for regular bits of fuel can be a drawback.
.There are plants like the Kentucky Coffee tree, that produce huge amounts of seed, enough to be a nuisance.
They might be useful as fuel with very minimal processing.