Clean, smart energy

ROMA – KENEUOE Rantalane’s charcoal burns cleanly.
In fact, you can easily burn it inside your house without fear of smoke.

It also provides constant heat for your barbeque for hours.

“As I compare its properties to foreign brands in the market,” said the National University of Lesotho (NUL) student, “I am convinced that my charcoal is way better.”

As part of the innovation spirit that is sweeping Lesotho’s youngsters, Ratalane didn’t just want to produce a charcoal simply to replace foreign brands.
She wanted a product that would be of choice because of its superior properties.

And so her charcoal comes in the form of briquettes.
The difference is that briquettes are formed into a particular shape to achieve a specific aim.

In her case, it’s about burning better.
But what is charcoal?

In short, it is an organic material that has a high concentration of carbon.
Ordinary wood we use for cooking has a lot of things in it.

These include water and volatile materials; materials that evaporate easily.
When you burn wood, the water and volatiles are the first to leave.

And this results in inefficient burning.
There is less energy released per mass of wood because part of the wood is made of materials that do not necessarily release heat, such as water, materials which, in fact, do the opposite.

Many people like seeing a flame when they are cooking.
That flame is actually volatile gases escaping the wood and they do not necessarily make for a good burning.

Then there are particles that we often call smoke, which is bad for your health.
Those things aren’t good for your health, oh.

Due to inefficient burning, ordinary wood produces a lot of smoke because of incomplete burning.

“That is why we use charcoal, especially when we are barbecuing here in Lesotho,” Keneuoe said.

“The most important thing we need is heat. We don’t need the flame, we don’t need the smoke and we don’t even need the steam.”

To make charcoal, she first took the organic matter, mainly waste wood.She then applied heat to the wood particles in an environment where there was no oxygen.
Oxygen causes burning, so when you heat wood without oxygen, there is no burning but water and volatiles are driven off.

“As you drive out water and some volatiles, you are actually leaving more and more of carbon in the wood,” she said.

Why is that important?
Carbon is the main material in wood that takes part in the burning process.

When carbon reacts with oxygen in the process of burning, two products are released: carbon dioxide and heat.
The purer the carbon, the better the burning.

Shape of charcoal is no laughing matter either.
With everything being equal, shape can determine whether the charcoal is considered good or not.

When you take charcoal and turn it into a specific shape, it is now called a briquette.

“As you can see, my briquettes took a rounder shape with holes in between,” Keneuoe said.

She suggests that particularly the holes in the middle of the rounded briquettes make for good burning as they allow for a freer flow of oxygen.
Unlike other forms of charcoal, which are mostly nothing more than treated lumps of wood, her charcoal is made of smaller and ground particles.

The particles are then held together by clay.
Clay as a binder can withstand fire, does not give out fumes when it is burned and can retain some of the heat and release it slowly, enhancing the properties of the briquettes.

Here were the properties of her briquettes compared to the foreign brands:
Volatiles: too much volatiles mean a lot of toxic substances released during burning.

While 40 percent or less is recommended, her briquettes had around 34 percent volatiles and the foreign brand had around 26 percent.
Carbon content: the more carbon a charcoal has, the more energy it will release.

The recommended value is between 50 and 90 percent.
Hers had 54 percent carbon and the foreign brand had 60 percent.

Moisture content: The more moisture there is in charcoal, the harder it is to burn it.
While moisture content of 10 percent or less is recommended, hers had a moisture content of around 6.5 percent while the foreign brand had a moisture content of around 5.2 percent.

Ash Content: Ash in charcoal does not take part in the burning process.
While an ash content of five percent or less is recommended, hers had an ash content of around four percent while the foreign brand had the ash content of around three percent.

Yet her charcoal takes roughly three hours of burning compared to two hours for the foreign brand.
Also, during burning, hers provided no smoke while the imported brand gave smoke continually.

In the end, she thinks that while the properties of the foreign brand were slightly better, her use of clay, her grinding of the charcoal to increase surface area and the shape she chose made all the difference.

Own Correspondent