Greentech Environmental Solutions GambiaSEED Awards 2011 Winner
GreenTech Gambia GreenTech Gambia GreenTech Gambia

What is a groundnut shell briquette?

A groundnut shell briquette is basically crumbled and pressed groundnut shells. Due to their high calorific value, the groundnut shell briquettes are a valuable solid biofuel. Thus they are an environmentally friendly and economically efficient alternative to firewood and charcoal. GreenTech produces briquettes in zylindric shape with a heavy duty machine. Due to their smooth surface and unified shape, briquettes are comfortable to handle, transport and store. Briquettes work best in fuel efficient stoves.

What are the briquettes made of?

GreenTech’s groundnut shell briquettes are purely made of the groundnut shells, as they are dumped after decoating by the Gambian Groundnut Company. There is no chemical added to make them stick together or burn faster. When collecting the groundnut shells, visible foreign material, such as plastic, paper, stones or cloth, which are occasionally found on the dumping site, are sorted out manually.

What makes the briquettes so compact?

The briquetting machine crumbles, heats and presses the groundnut shells. Like every solid biomass, groundnutshells contain lignin, a naturally binder, which is liquefied through the heat. The machine is then pounding a specific amount of shells with the force of two tons four times a second in a chamber before releasing it on the cooling line. There, the lignin hardens again, glueing the compressed shell crumbs together. The correct humidity of the raw groundnutshell plays an important role in the process, as the briquettes would fall apart, if pressed too dry and also break from released steam, if too moisture. It took GreenTech about 20 hours of machine operation, testing and adjusting humidity and pressure levels, to finally achieve the targeted quality, which you can purchase today.

Where do you use briquettes?

For households, the briquettes work best in fuel efficient stoves, explicitly in Rockefier Stove. Some restaurants and bakeries are currently testing GreenTech briquettes in their existing systems. Industries are testing it for their boilers. Smokeries can use the briquettes for fish processing. Experienced briquette users are even using it for their barbecue, but we can only advise this to “briquette experts”, as it might smoke, if not handled correct. There are probably many more uses to be explored, and if you already have a stove or oven, it is a matter of testing it. Generally briquettes work best in a semi-closed system, as too much ventilation makes them burn too fast at high temperatures, which is not suitable for usual food processing. Anyway, wherever you intend to use it, it is highly advised to get a short introduction from authorised GreenTech staff, as briquettes are handled slightly different than charcoal or firewood, i.e. briquettes must not be turned over through shaking or poking-just relax and let the briquettes glow through as they sit, otherwise they fall apart and the fire goes off with smoke. To understand the nature of briquettes better, GreenTech provides demonstration and testing services at the plant and in the field. As the briquettes work in most isolated settings, it is just a matter of handling them correctly. Just contact us for an appointment: 6662622 or [email protected]

What is a fuel efficient stove/ energy saving stove?

The name already hints the idea behind fuel efficient or also called energy saving stoves: It uses solid biofuels more efficient and thus saves fuel and energy. This is mainly achieved through better isolation and ventilation, compared to the traditional open cooking settings. There are diverse versions of fuel efficient/energy saving stoves, serving different purposes and likings. For GreenTech Briquettes, the Rockefier Stove worked best, so far.

What is a “Rockefier” Stove?

The Rockefier Stove is the type of fuel efficient stoves, which GreenTech found most suitable for households and commercial/large scale food processors so far. GreenTech and partners researched diverse design of fuel efficient stoves on the internet and from the combined idea of the Rocket Stove and the Gasefier Stove, GreenTech eventually developed a locally adequate version, amended to users’ needs. The so called “Rockefier” Stove can be made by local weldermen from recycled metal for a well affordable price. It is well isolated through a ring that is filled with sand or mud. It has a pipe for ventilation, fuel feeding and ignition on the side and a lid for an efficient two-phase cooking system. Used in combination with briquettes, it can actually pay off in less than one month for a 10 member household, switching from traditional charcoal cooking settings. The Rockefier Stove is easy to handle and no rocket science at all.

Why is it called “Forno Nopal”?

Users started to call the Rockefier Stove the “Forno Nopal”, as it cooks calmly and the cook does not have to worry much about keeping the fire up. Users state that it is a more relaxed, comfortable, time and money saving cooking procedure, since they use their “Forno Nopal” with GreenTech briquettes.

How to prepare the briquettes?

Briquettes are very comfortable to use, as you can break them by hand in the required size and amount needed for your cooking.

How do you light the briquettes?

You basically light them the same way as firewood. In our testing, thoroughly dried organic matter, such as wood split, grass or coconut palm bark, worked a lot better for ignition than paper or cardboard.

Following technique worked best in our testings:

  1. Place the ignition help (as dried grass, etc.) on the bottom of the stove and have it come through the side pipe a bit.
  2. Then place a layer of briquette slices (two to three fingers wide) on top of the grass.
  3. Light your match and light the grass through the side pipe.
  4. Fan only a little bit, rather not at all, if the flames are coming up.
  5. The fire might smoke, as long as your ignition help is burning, but once the briquettes catch fire, the smoke fades and you can place the lid and pot on the fire.
  6. If you put too little amount of briquettes at the beginning and you want to add more heat, just add briquettes gently through the side pipe, without blocking the ventilation.

Please note, that you might not see much of a flame or smoke after a few minutes from ignition, but you will realize that the heat is strong and will cook your meal.

Please note as well, that the fire can be ready for cooking within two minutes, if you use a good ignition technique. Therefore it is advisable to prepare your food before lighting the stove and start cooking immediately, not to waste any briquettes.

We highly advise to light the stove outdoors, as smoke occurs at ignition. Once the briquettes caught fire and smoke is not visible, the stove might be moved indoors, but make sure the room is well ventilated, as it is a rule for cooking with all other biomass.

If you have any problems with ignition or smoke, call for our training service: 6662622.

How do I keep the fire up?

Once the cooking heat is generated, the fire must not be disturbed by shaking, poking or turning the fuel over. You may add briquettes to generate more heat, if needed. If you use the Rockefier Stove, there is no need to take off the pot to add briquettes: You just add slices of briquettes gently through the side pipe; just make sure the added briquette is far enough inside the stove and not blocking the ventilation through the opening. We do not advise to dump briquettes from the top of the Rockefierr Stove, as it might disturb the fire for a while; but nevertheless, once the briquettes catch fire, it will be back to normal. Once you only need a low flame, i.e. for simmering the rice, do not add briquettes, but make use of the two phase cooking technique of the Rockefier Stove.

What is the Two-Phase-Cooking Technique on the Rockefier Stove?

For the Rockefier Stove, as promoted by GreenTech, there is a two phase cooking technique, that will safe you even more fuel. Once you only need lower heat for simmering your rice or sauce, follow these simple steps:

  1. Take the pot off the lid and place it aside,
  2. remove the lid with the help of the metal triangle as a hook (careful, the lid is hot!).
  3. Place the metal triangle straight on the opening and then
  4. put back the pot straight on the triangle.

Thus your pot sits lower to the glow, no need to add more briquettes. Saves you even more fuel!

How much do I have to use?

Cooking a traditional dish, such as Benachin or Domoda, for 12 adults, you would need about 2-2,5kg briquettes. The exact amount will eventually depend on the amount and type of food you cook and your general cooking habits. Therefore you will have to test it a few times. Rather light less, as you can always add more briquettes during the cooking process.

How much does it save me to cook with briquettes and Rockefier stoves?

This will depend on your cooking habits, for how many people you are cooking and what setting you used before. In our testing, we used about 2.5 kg to cook a traditional meal (Benachin or Domoda) for 12 adults. As retailers will sell the briquettes for about 6 Dalasis (5 Dalasi at the plant), it would have cost 15 Dalasis for 2.5 kg. For the same dish our testing cook used in a traditional charcoal forno a minimum of 2 kg charcoal, costing 39 dalasis in retail. Thus it saved 24 dalasis per cooking for 12 adults, 48 dalasis, if warm dishes are cooked twice daily. The Rocket Stove (350 Dalasis) would have paid off for this cook within a week.

Further, the cooking process took about 30 minutes less with the Rocket Stove/Briquette unit, valuable time to use for other activities! And just imagine how many trees and carbon emission you can save by using the Rocket Stove/Briquette unit.

Where can I get service, training or instructions?

GreenTech offers a tour of the plant and a user demonstration on the Rockefier Stove/GreenTech Briquette Unit every Wednesday, 11am at the plant in Kololi/Senegambia, right behind the Tourism Security Unit.

Who can help me, if I cannot afford a stove at once?

GreenTech is trying to find subsidies for stove distribution, but so far no donor could be found. We can only advise needy groups, associations or individuals to write their own application or proposals to potential donors. Nevertheless, we observed that it is not worth to wait too long for a donor, as the money saved on cooking fuel through the use of a Rockefier Stove might be more within a month than the investment in a stove. The Rockefier Stove is basically a saving account. We calculated that a cooking unit of 12 adults, switching from traditional cooking with charcoal in an open forno, will save about 10.000 GMD over one year, if two meals are cooked per day.

What is the advantage of using GreenTech Briquettes in the Rockefier Stove?

Using GreenTech Briquettes you are mitigating environmental challenges, locally, regionally and globally. At the same time you will save yourself costs, time and effort. The briquettes are easy and comfortable to transport store and handle due to their unified shape and compactness. Briquettes are easy to break in the amount needed to cook, no need for tools, no dirty hands. The heat produced with Greentech Briquettes in the Rockefier is strong and long lasting. The Rockefier Stove is simple to handle and there is no need to fan or turn the fuel once it is lit.

How does the use of GreenTech Briquettes in Rockefier Stoves mitigate environmental challenges?

Using GreenTech Briquettes in the Rockefier Stove helps to

  1. save forest and biodiversity as briquettes form an alternative cooking fuel, reducing the need of forest explitation for firewood and charcoal
  2. manage waste, as the groundnutshells are used
  3. reduce air pollution as complete combustion process in the Rockefier Stove reduces visible smoke
  4. reduce CO2 emission, as less fuel is burned in the Rockefier Stove and grounnutshells do not have to be burned on the dumping site
  5. build CO2 sinks, as forests can regrow
  6. mitigate climate change through CO2 reduction

Saving forests has multiple secondary effects as soil protection, windbreaker, livelihood improvement and the protection of natural and cultural heritage.

How is the use of briquettes reducing greenhousegases?/Why is the use of briquettes considered as climate change mitigation?

CO2 is considered as the major factor for climate change. It is a greenhouse gas. CO2 is released, when biomass is burned. Plants, especially trees bind C02, thus functioning as a carbon sink.

Thus, the more forest we can save, the more less biomass we burn, the less C02 we set free (carbon foot print), the more we contribute to mitigate climate.

Groundnutshell briquettes from an alternative to firewood and charcoal, thus save the forest, building CO2 sinks. Using the calorific value of the groundnutshells in the Rockefier stove for cooking, makes the combustion more efficient, thus reducing less CO2 than traditional cooking settings or the burning of grounnutshells as pure waste management.

Don’t the briquettes smoke a lot?

No, not if you use the right setting, as the Rockefier Stove. Respectively if you become an expert in using briquettes and know their burning features, you might even use them successful in different settings. We even found that GreenTech briquettes in Rockefier Stoves smoke visibly less than traditional cooking settings. Smoke is mainly caused at ignition, due to burning ignition material and the low starting temperature. Once the briquettes caught fire and the lid is on the Rockefier, smoke is hardly visible. If you feel you experience too much smoke using the briquettes, please call us for advise, as it is usually a matter of ventilation or ignition techniques. Often the stoves are overfilled as customers can hardly believe that they could cook a meal for the entire family with only a few pieces of briquettes.

Can they also be used for industries?

Generally briquettes can also be used in industrial boilers, ovens and stoves, where other biomass is used. Briquettes were experienced to burn stronger than firewood or loose groundnutshells. GreenTech is currently testing diverse settings. Please contact us, if you would like to test the briquettes in your industrial setting.

Can Briquettes and Rockefier Stoves be used for single households?

GreenTech Briquettes and Rockefier Stove have initially been intended for households, to mitigate the upwinding household energy crises. The normal size stove can easily cook for 20 adults, but is also efficient for single households. There are specific sizes for catering or commercial food processors and for attaya cooking.

Can I use it for my BBQ?

If you are an experienced briquette user you might try it, but it will also depend on the type of BBQ. Generally we do not advise it to inexperienced briquette users, as it can be disappointing, if you do not know how to handle the briquettes. Combustion and ventilation have to be worked out to avoid smoke. Therefore, just call us for advise, if you plan to use it on your BBQ: 6662622

How long is the cooking process with briquettes?

In our testing, the cooking process with briquettes in the Rockefier was clearly faster than in the traditional charcoal or firewood setting, as briquettes do not need preparation and the cooking heat is almost instantly generated. The heat is strong and long lasting. So, have your food prepared before lighting the briquettes in the Rockefier!

Can it be used for indoor cooking?

Generally GreenTech would rather discourage indoor cooking for any biomass in any setting, thus also for briquettes in the Rockefier, as cooking in the fresh air will always be healthiest. Nevertheless, if you have an indoor or semi-indoor kitchen and want to use briquettes with the Rockefier inside, you should start ignition outdoors and move the stove only indoors, when the flames are visible, the lid is on and the smoke clearly reduced (will take about 2 minutes from lighting the match). As for cooking with firewood or charcoal indoors, you should ensure the room is well ventilated.