2. Photovoltaics as an energy option for rural areas: benefits and over all social and economic context
GTZ is currently implementing more than 20 projects In the Third
World in which photovoltaics plays an important role. As of 1991, PV systems of
various types with a total output of about 400 kWp had been installed in GTZ
projects, and current plans call for this figure to be doubled to around 800 kWp
by the year 1993.
Components of a photovoltaic system
The illustration on the left shows the structure of a simple
photovoltaic system. In most instances, solar generators must be supplemented by
storage batteries and electronic charging/regulating devices.
Graphic: Siemens
However, photovoltaics as an energy source for rural areas must
be seen within the following overall context:
- Over 90 % of the energy consumed by rural
households is used for cooking. Photovoltaic systems are not suitable for
meeting these needs.
- Nonetheless, the way in which these households obtain the
remaining 10 % of their energy requirements has a major impact on the quality of
life in rural areas. For example, the inhabitants of such areas attach great
importance to having modem lighting in their dwellings and having access to
modem communications media such as radio and television, and the requisite
electric power can be supplied by the environmentally friendly photovoltaic
technology.
- Although the target group of dissemination measures includes
the poorest of the poor in developing countries, investments in this superior
technological option are still worthwhile because this target group presently
spends a large part of its scarce monetary resources on traditional energy
sources. Over time, photovoltaic systems will cost the same as the traditional
options they are now using, but the PV technology supplies a form of energy that
is not only of much higher quality; It is also more reliable than the
conventional alternatives and exposes the users to far fewer health risks than
those alternatives.
The amounts which households now spend on kerosene and dry-cell
batteries are roughly equivalent to what they would have to pay in order to
finance a photovoltaic system under annuity conditions (see Table 1). From the
point of view of household energy consumers, however, there is an important
difference between the two options: With the one they are burdened with a
long-term financial obligation involving the repayment of a sizeable debt, while
with the other they are free to purchase conventional energy sources on an ad
hoc basis in accordance with their needs and financial resources. Thus, the
question of financing is of crucial importance for the success of dissemination
measures for PV systems which are aimed at low-income segments of the
population.
Smaller photovoltaic systems in particular - which are generally
referred to as solar home systems (SHS) - have a number of secondary benefits
that are important in terms of both raising the individual users' living
standards and helping to narrow the existing gap between urban and rural areas
in terms of their level of infrastructural development. Although their direct
impact on national energy balances will be small for a long time to come, the
use of SHS can conserve conventional energy resources and at the same time yield
indirect energy savings, e. 9. by eliminating the necessity of transporting
batteries. They can also be expected to produce tangible environmental benefits.
The introduction of SHS leads to a noticeable improvement in the
users' standard of living, above all through positive impacts that cannot easily
be measured in monetary terms:
- Significantly better light is available, with
benefits such as reduced eye strain.
- The smoke and fire hazards in the home that are associated
with traditional indoor light sources (e. 9. candles, oil lamps) are eliminated.
- There is no danger of children burning themselves if they come
in contact with the light source.
- A constant, reliable supply of energy is ensured.
- The improved light makes it possible for the members of the
household to engage in productive activities during the evening hours.
- SHS are a much more environmentally friendly source of
electricity than dry-cell batteries, which contain highly toxic substances and
often end up as "toys" in the hands of children or are disposed of in such a way
that they pollute sources of drinking water or the soil in livestock grazing
areas.
- The utilization of SHS also gives users the feeling that they
are participating in, and benefiting from, technical progress.
- Although automobile batteries are already being used for
lighting and to power devices such as television sets, their service life is
greatly prolonged when they are utilized as part of an SHS: When they are
recharged with standard battery chargers like those found in car repair shops,
they are often charged too rapidly, and in many cases the users wait too long to
have their batteries recharged, thus allowing them to deep discharge to a
dangerously low level. Moreover, with SHS the heavy, cumbersome batteries do not
need to be regularly disconnected and transported to a charging facility, a
time-consuming and sometimes difficult task.
The fact that small photovoltaic systems are available on a
large scale and are an affordable option for a significant percentage of the
rural population means that measures that will significantly enhance the quality
of people's life can now also be carried out in the countryside. Indeed, with
photovoltaics the energy supply situation in remote rural areas can be improved
to the point that the gap between rural and urban dwellers in terms of the basic
material comforts and overall "lifestyle" which they enjoy is visibly narrowed.
Moreover, when SHS are utilized, individualized systems can often be supplied
which meet the needs of specific consumers and can also be largely financed by
the users, resulting in savings for the government (cheaper than
state-subsidized grid-based electrification programs). This is an especially
attractive option for rural areas that are not likely to be connected to the
national or regional power grid in the foreseeable future (i. e. the promotion
of individual household electrification using SHS is a viable rural energy
policy).
There are still only a very small number of photovoltaic systems
In operation in developing countries, and they have only a negligible impact on
national energy consumption. But photovoltaic systems can help to reduce the
adverse effects of conventional energy consumption on the climate and the
environment if they are mass-produced and employed on a large scale not only in
the countryside but also in urban areas. For instance, they can greatly reduce
the pollution caused by the improper disposal of dry- cell batteries, millions
of which are currently decaying and releasing their toxic contents (heavy
metals) into the soil and the groundwater in developing countries. This type of
environmental degradation can be avoided by using SHS, although it is usually
first necessary to establish a recycling system for the storage batteries that
are used in the systems.
Thus, the decision for or against the utilization of
decentralized photovoltaic systems will be based on an assessment of factors
that operate at three different levels:
- Micro-economic feasibility, i. e. for individual
households.
- Economic benefits accruing to user households, taking into
account the positive impacts on individual consumers' overall standard of
living, including those which are usually unquantifiable, i. e. difficult or
impossible to express in monetary terms.
- Macro-economic cost-benefit considerations.
When contemplating the initiation of a broad-based dissemination
campaign, energy planners must take all three of these levels into account if
they are to arrive at an accurate assessment of both the campaign's prospects
for success (- acceptance by users) and the desirability of large-scale
dissemination from the stand-point of the economy as a whole. Certain parameters
are difficult to quantify but they nevertheless have a major influence on the
target group's attitude toward the technology; these factors include subjective
judgements as to whether or not it is advantageous to own photovoltaic systems,
and here criteria such as "modern" (= taking part in technical progress) and
"prestigious" will play an important role in the thinking of members of rural
middle and upper classes. In the eyes of these target groups, the fact that the
SHS technology is a "time saver" and is "more convenient" than the conventional
energy technologies which it substitutes can also be an important selling
point.
