|VESTO - THE VARIABLE ENERGY STOVE|
NEWS FLASH: Johannesburg, South Africa, 9 September 2004
The Vesto has been given the Chairman's Special Award for design by the Design Institute of South Africa (DISA) . The stove was also a winner in the Houseware category of the annual event held by the South African Bureau of Standards to promote design excellence.
Check for details in the Farmer's Weekly magazine and the Mail and Guardian newspaper or on the SABS website.
The Vesto is a variable energy, fuel efficient wood burning stove based on a modified 25 litre paint can. It is a significant change from the approach taken with the Tsotso Stove and its variants the Basintuthu and Shisa Stoves. It has preheated secondary air of three types as well as preheated primary air. The primary air and most of the secondary air are separately controlled by two horizontally sliding levers that protrude from one side of the body. It can accommodate fuel from twigs up to 110mm diameter wood, preferably 200mm long or less (over-filling a wood stove make a lot of smoke).
The Vesto was developed from the beginning as a stove that would be mass produced, rather than made through artisanal production in villages. This is because is intended by its developers to make an impact on the consumption of wood of such a large scale that it would be like planting and raising an entire 'virtual forest'. In order to reach a scale of market acceptance and to generate sufficient fuel savings it was necessary to use materials, production processes and marketing strategies that could produce, assemble and distribute the stove at a cost similar to a large pot - in the region of $20 to $30 while still allowing for a retailer to sell it profitably.
One of the events that influenced this choice of technologies was the recent closure of India's subsidized fuel efficient stove distribution programme which has been running for about 16 years. The public sector promotion model is not working well anywhere in the world on a scale sufficient to generate the savings of fuel a big enough scale. To be successful in the private sector, one has to adequately address issues of emissions, fuel consumption, fuel variation, life, power variability and appearance. Several of these issues are very difficult to deal with appropriately with artisanal production, even though hand fabrication remains possible.
The stove was developed by Crispin Pemberton-Pigott and the multi-level marketing plan was developed by Rina King of Johannesburg. Parts production is being handled by several specialized sub-contractors. Assembly can be centralized or regional if the volumes warrant it. The distribution of a low-cost item like this is a major challenge. The parts can be cheaply shipped packed and nested but shipping a boxed, assembled stove to a supermarket can be expensive because it is more air than mass.
The Vesto consists of five main components:
- the main stove body with a wire handle
- the fire grate with holes punched through it, including a replaceable insert at the bottom
- the folded stainless steel strip to support the pots.
- the secondary air controller
- the primary air controller.
Have a look at how to braai with a Vesto (BBQ).
For more variable energy Vesto Stove information please contact us at firstname.lastname@example.org
Movie of the Vesto gasifier prototype here (4,706 KB)
Movie of the vortex created by the Vesto here (1,106 KB)
This picture shows the stove as it is sold and opened for use. The left lever controls the primary and lower secondary air supply and the right one controls the middle secondary air supply. Left is closed and right is open.
A top view looking right through the stove shows the top deck, the folded strip pot stand, the fire grate and the replaceable insert at the bottom. The bottom of the stove is open so it has to rest on a flat surface of else be snuggled into the soil or sand to seal the air properly and prevent it from entering the lower part of the stove.
Optional Braai (Bar-B-Q) Plate with stand. The stand can also hold large flat bottomed pots and pans.
A4 paper size, 2-Fold flyer with Basic operation instructions: