TChar StovesFor Haiti and East Africa (and beyond)

Bob Fairchild solarbobky@yahoo.comETHOS 2012

Cut down the tree, dig out the roots

Traditional charcoal production

From a distance

What is a TChar?

• A TLUD microgasifier top “TTop” and charcoal stove or quench base bottom “TBottom”

• The TTop lifts off to drop the char into the TBottom

• The char can be used to continue cooking in a charcoal stove or quenched in a quench base for later use as cooking charcoal or biochar

Why a TChar?

• In cultures that use charcoal as a cooking fuel it may be difficult to convince them to bury it

• Allowing the char to burn to ash in a TLUD is inefficient and significantly shortens the life of the TLUD

• Most TLUD’s require lifting and dumping to get the char out – this can be awkward and dangerous

Early prototypes - East Africa

Reconceptualization- KentuckyLoose fit, lift to drop charcoal

Add base ring for stability

Add outer cylinder for stability, safety, and preheating secondary air

Drop in concentrator ring with j-bolt

Add upper ring for stability and secondary air channeling

First prototype - KentuckyTChar on charcoal jiko

Fire!

We have lift off!

Hot charcoal for continued cooking

Some alternative features

• Central secondary air inlets• Drop bottom• Quench base

Central secondary air inlets

Will it reduce black carbon?

Drop bottom and quench base

• True butterfly “valve”• Integral primary air inlets• “air tight”/ water tight container

Integral primary air

True butterfly valve

Pull rod to “open” valve

“Complete” stove Less pot support and skirtLess primary air plugs

FUELS

• Dry • Chunky• No other uses

Spanish lime seed grenn kenep (mamoncillo Sp.) Melicoccus bijugatus

semans zaman Tropical almond seed Terminalia catappa

Bamboo chunks ti moso bambu yo

Coconut shell gous kokoye

Peanut shells gous pistach yo

Other possible fuels

• Citrus peels• Coffee hulls• Wood shavings• Corn cob chunks (but often fed to pigs)• Grass bundles• 1” dia micro briquettes: paper waste, grass,

tree leaves/twigs but require shredding, forming, and drying

Challenging fuelEuphorbia lactea – thorny hedge plant with milky latex -kandelab

General design considerations

• Beyond a conventional TLUD:– Sized to fit depth of charcoal stove (adjustable?)– Sized to not exceed volume of base– Stable on base– Easily and safely removed for dropping char

For more information

• www.drtlud.com• TChar Technology Part A: Introduction• TChar Technology Part B: Construction• More coming soon

• Special thanks to Paul Anderson “Dr. TLUD” and Christa Roth