[Stoves] Improve gas burners efficiency?

[Anand Karve]

Dear Ron.
the gap width between the pot and the jacket surrounding it was
determined by trial and error. We have not kept the data of these
trials. Also, when these cookers are fabricated, the fabricators often
face difficulties in adhering to the exact specifications. So the
cookers being offered to users have gaps ranging approximately between
0.5 and 1 cm between the cooker and its jacket.
Yours
A.D.Karve
On Sun, Jul 31, 2011 at 9:15 PM, Ron Larson <rongretlarson at comcast.net> wrote:
> A D:
>
>    Can you provide more data on the optimum gap width for your Serai cooker?
>
> Ron
>
> Sent from my iPad
>
> On Jul 31, 2011, at 12:19 AM, Anand Karve <adkarve at gmail.com> wrote:
>
>> Dear Xavier,
>> we have worked with skirtings around pots. They work best, if they are
>> pot-specific. Our Sarai cooker uses just 100 g charcoal to cook rice,
>> beans and vegetables (or meat) for a family of 4 to 5 persons. The
>> entire cooker is surrounded by a stainless steel sleeve, which directs
>> the hot flue gases to flow through the gap between the cooker and the
>> sleeve. The efficiency of the cooker is increased because all the flue
>> gases remain in contact with the entire outer surface of the cooker.
>> If the cooker is used without this jacket, it requires at least 4
>> times as much fuel to cook the same quantity of food. Jackets can be
>> designed for pots in restaurants, where they generally have a standard
>> pot for each function (a specific pot for rice, another for
>> vegetables, and still another for deep frying etc.) But in a
>> household, where the housewife may be using at least 20 to 30 pots of
>> different sizes, it would cost a lot of money to make sleeves for each
>> pot.
>> Yours
>> A.D.Karve
>> On Sat, Jul 30, 2011 at 2:59 AM, Xavier Brandao <xvr.brandao at gmail.com> wrote:
>>> Dear stovers,
>>>
>>>
>>>
>>> When promoting the institutional rocket stoves in public administrations
>>> kitchens, restaurants, hotels in South Benin, mostly in the cities of
>>> Cotonou and Porto-Novo, I am told more than once that wood is not used
>>> anymore, because of the smoke, the cost, or the hassle. Many moved to gas
>>> burners, which is of course great. We produce and sell wood stoves, but we
>>> always encourage people to use gas cookers, because they are cleaner, more
>>> ecological and economical. We only produce wood stoves for people who would
>>> have use wood for cooking anyway (for certain dishes, certain quantities, or
>>> in certain big institutions).
>>>
>>>
>>>
>>> Many people liked the sturdy design of the stoves and asked if they could
>>> have the same for gas stoves. I always reply that is was designed for wood
>>> only, and promise we’ll think about a model for gas burners.
>>>
>>>
>>>
>>> My question is: how much can a gas burner be improved in terms of energy
>>> efficiency? Is it worth spending metal in making a skirt around the burner
>>> and the pot? I was thinking also of a surface under the burner, perhaps just
>>> like the institutional stoves, made of a mix of clay, to radiate heat
>>> upwards. It would give a traditional look to a modern cooking device.
>>>
>>>
>>>
>>> My quick calculations showed it could cost in the very very worst case up to
>>> 30 000 CFA francs all included (about 45 euros) for a skirt for one burner.
>>> People seem to be ready to pay that, if it means savings. A lady who runs a
>>> restaurant paid a welder 60 000 CFA for two skirts, which amusingly enough
>>> is in line with my calculations. They are not made yet, I’m curious to see
>>> how they look.
>>>
>>>
>>>
>>> Here is a picture of the burners:
>>>
>>> http://imageshack.us/photo/my-images/803/rimg1222.jpg/
>>>
>>> Another burner, inserted in a truck rim:
>>>
>>> http://imageshack.us/photo/my-images/834/rimg1229.jpg/
>>>
>>> Here is a picture of a small burner, with a small skirt which only protects
>>> the flame from wind, not the pot:
>>>
>>> http://imageshack.us/photo/my-images/38/rimg1228.jpg/
>>>
>>>
>>>
>>> I’ve searched a bit on Bioenergylist, and in Micro Gasification Cooking with
>>> gas from biomass, I could only find the Vesto stove as a gas stove with a
>>> skirt.
>>>
>>>
>>>
>>> This post brings another question, which I will detail in another issue.
>>>
>>>
>>>
>>> Thanks in advance,
>>>
>>>
>>>
>>> Xavier
>>>
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>>>
>>>
>>>
>>
>>
>>
>> --
>> ***
>> Dr. A.D. Karve
>> President, Appropriate Rural Technology Institute (ARTI)
>>
>> *Please change my email address in your records to: adkarve at gmail.com *
>>
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>>
>
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>



-- 
***
Dr. A.D. Karve
President, Appropriate Rural Technology Institute (ARTI)

*Please change my email address in your records to: adkarve at gmail.com *