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Household energy in high regions
Energies domestiques dans zones de haute altitude
L'auteur souligne que l'analyse des besoins de chauffage des locaux
dans les régions de haute moutagnes requiert des approches
spécifiques. Les foyers multi-usages (cuisson et chauffage) sont
encore peu répandus quoique les technologies sont disponibles.
Généralement, les programmes sur les foyers n'accordent que peu de
place à la conception d'équipements multi-usages. Le moyen le plus
simple de chauffer des locaux est d'utiliser la cheminée comme
radiateur. Cependant l'optimisation des deux fonctions implique
davantage d'efforts en matiêre recherches développement. Quant au
chauffage solaire des locaux, les couts restent extremement élevés.
Dans quelques zones montagneuses du Népal, ITDG a introduit des
équipements de cuisson utilisant l'électricité. Les recherches qui
ont ete menées pour accroitre l'efficacité de cuisson n'ont pas
retenu l'attention des usagers dans la mésure où les pertes de
chaleur servaient en fait au chauffage des locaux. Cet exemple
montre que les stratégies de promotion des foyers à usages
multiples sont différentes de celles ayant pour seul objet la
diffusion de foyers utilisés principalement pour la cuisson. |
This article is based on conclusions reached in the regional
workshop on space heating in Pokhara, Nepal, February 1996.
[top]
[end]Cold
altitudes and the need for space heating
A large majority of people in the developing countries live in hot
climates and there is a need for coolness rather than heating in
their homes. Nevenheless, there are many millions, particularly in
the Himalayas or Andes, for whom heating is essential for survival,
or is needed for a tolerable existence.
Mountain people have been largely overlooked in the design of
household energy programmes and stoves and, as a result, space
heating has never figured prominently in studies of energy
policy.
Where stoves provide a heating function, they are often in rooms
which are badly ventilated, in order to prevent heat loss. The
resulting exposure to severe indoor air pollution is known to be
bad for the health of both the stove users and other family
members. Although the use of chimneys can help in reducing many of
the harmful components in the room, they are not a cure for smoke
problems. Fires may bum faster due to the improved draught, heat
will be lost through them and fuel will be wasted.
[top]
[end]Biomass
use in mountain areas
As in almost all developing countries, biomass is the main source
of energy for cooking and space heating and it is expected to
remain so for the foreseeable future. The reasons are:
- A reliable supply of biomass is usually locally available.
- It is almost always the cheapest available fuel if the fuel has
to be bought.
- Use of biomass is traditional and women are skilled in
fuel
- Stoves have been designed or adapted to the local biomass
fuels.
- There may be no other fuels available.
[top]
[end]Meeting
household energy needs
[top]
[end]Stoves
with several uses
Some combined cooking and space heating stoves have been developed
with the aim of saving fuel, reducing environmental impact and
yielding a range of benefits to users, particularly savings in
time, work and money. Besides being able to afford an improved
stove, the need for information about its good and bad points needs
to be given to the user. If users do not know about the benefits
and problems associated with a new stove they will often stay with
the traditional stove.
Figure 1: Typical stove used in high
regions for cooking and space heating
|
Cookstoves often have several functions; cooking, space heating,
lighting, crop and fuel drying. social gathering etc. To succeed.
stove development needs to take account of the local conditions,
including house and stove construction materials and skills and the
effects of weather. Social and cooking habits, affordability,
complexity of the stove and ease of maintenance and repair need to
be carefully checked. The materials used for stove construction
should be obtained locally in view of the extreme difficulty of
transportation. Stoves need to suit the available fuels, pot sizes
and use (cooking on high heat, simmering, baking, special food
preparations etc.).
The need to design stoves which perform several functions is often
overlooked by stove programmes. In mountain areas, space heating is
an important energy need which merits far more emphasis in energy
policy and research.
The most straightforward way to provide space heating from a stove
is to use the chimney as a heat radiator. This means routing the
chimney through the room/s so as to transfer the heat from the
exhaust gases to the air around the chimney. In many places,
considerable local expertise on chimneys is available and can be
used at the design stage.
The Chinese under-floor heating system, the 'Kang-Lianzao' bed
stove (BP.29, page 33), may be appropriate for cold mountain
regions elsewhere.
[top]
[end]Solar
energy for space heating
Active solar systems collect energy from the sun and then move the
energy to storage or directly to the user by means of a transfer
medium such as water. They perform well for domestic water supply
but offer little for space heating. Adoption rates are very low due
to the initial cost for the householder.
Passive solar designs have produced promising results in
demonstration projects all over the world, notably on the high
plains of Bolivia at an altitude of over 4000 metres. Similar work
has been carried out by the LeDeG organisation in Ladakh. Passive
solar design employs the principles of positioning buildings to
achieve maximum winter insolation (incoming energy from the sun)
whilst minimising heat losses. Window design has also been
developed to a fine an. The trombe wall, which acts as a heat store
during the day and gives out heat to the dwelling during the
evening, is a simple device which also shows impressive results.
Figure 2: Kang-Lianzao bed stove
|
However promising the technical performance of these systems
appears, the obstacles to the spread of solar designs are
formidable. In particular, finding ways of influencing the design
of new dwellings is a real barrier to the technology. The challenge
of changing existing houses to adopt elements of solar design may
be too great. In general, the costs of incorporating solar design
into dwellings will restrict their spread beyond any but the most
wealthy communities or for communal buildings.
Stove programmes are often driven by the supply of the technology
itself. Too frequently, they take a narrow view of stove
development without considering other options which could achieve
the same goals, such as better maintenance of traditional stoves or
improving house construction.
During research into improved electric stoves for rural areas of
Nepal carried out over the last six years, ITDG worked in several
Himalayan communities. The electric stove incorporated a heat store
made from stones. During one phase of the work, the local team
tried to improve the insulation to this heat store, thereby saving
most of the heat generated for cooking. They soon learned that the
space heating characteristic of the new stove design was valued
much more highly by users than the project team had initially
imagined.
It is rare to find credit facilities and training programmes
provided to local entrepreneurs and manufacturers in mountain
communities. Availability of local materials for constructing space
heating stoves is very limited and the import or transport of these
materials increases the cost of stove manufacture.
Strategies for promoting heating stoves have to be different from
those used for cooking stoves because of the varying seasonal and
local requirements for heating energy.
- A stove programme must be integrated with related programmes
such as housing improvement, health and sanitation or
rehabilitation work following disasters.
- It should be used to promote traditional skills and
technologies and use local institutions.
- Improved stove dissemination should lit in with the financial
reality of households rather than the economic aims of
governments.
- Technology research and development for solar systems should
concentrate on cost reduction, for example, simple approaches using
locally available building materials may be suitable for reducing
the heat loss from the building.
Overall, a far greater understanding of the priorities of mountain
communities is required. Lessons from the commercial spread of
stoves in many countries have shown that successful stoves arc
those which meet the expectations of their purchasers rather than
the ambitions of their designers. A simple point, but fundamental
to bringing mountain communities more directly into work on
household energy.
[top]
[end]Contents:
Boiling Point 38: Household energy in high cold regions
.
|
Household energy in high regions -
Dissemination of improved stoves in Nepal -
Energy needs of tourist lodges in two mountain
communities in Nepal -
Stoves used for cooking, water heating and
space heating at high altitude in Nepal -
Household energy in high cold regions of
Morocco -
Status of improved stoves in the northern areas
of Pakistan -
High altitude space heating and cooking stoves
in Pakistan -
Heating-cum-cooking stoves of the FECT
Project -
Improved institutional stoves for Sudan
schools -
Haiti - Cooking stoves and domestic energy
-
Household energy in a recently electrified
rural settlement in Mpumalanga, South Africa -
Improved Tunisian domestic bread ovens -
Mumu - A traditional method of slow cooking in
Papua New Guinea -
Reducing the risks of poisonous emissions from
stoves -
Research into integrating a wood or charcoal
stove into building design
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