THE RENEWABLE ENERGY IN TUNISIA

GUELLOUZ Khereddine

AGENCE POUR LA MAITRISE DE LINERGIE 3, Rue 8000 MONTPLAISIR TUNIS - 1002

TUNISIE

ABSTRACT

TUNISIA is situated at the south Coast of mediteraneen sea between the 30th and 37 th parallel and has a high time duration of sunlight and for some regions a good speed of wind. Tunisia is also an agricultural country. (Annex 1). For these reasons, renewable energies could have a large range of utilisations there. The A.M.E was founded to put on and to manage the government policy in the Renewable Energies Field. This report will summerise the Tunisian Program as to the use of the different Renewable Energy Sources, the results and the future actions to be taken.

TUNISIA CHARACTERISTICS

TUNISIA is characterised by a long coast (1300 km) where 70% of the population is agglomerated in towns and villages. In the Northen and central Inland areas, where agriculture is prevailing, the population is disseminated ; Towns and Villages are less important.

In the South, witch has a subsaharian climate, the population is agglomerated around the OASES.

The sun is shining all over the year on Tunisia, there are a few days which are cloudy but there are some differences between winter and summer and between Nord and South :

Sunshine duration/year

Medium Sun energy radiation Winter Summer

North

2800 hours

2,3 kwh/m'/day 5,8 kwh/m'/day

South

3200 hours

4,1 kwh/m'/day 7,5 kwh/m'/day

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The wind potential is situated mainly on the North Coast, the medium speed is about 6 -7 m/s

Forests are in the North west on the Atlas mountains which do not exceed 900 m in attitude ; and cover

about 6% of the country surface. Wood is used almost exclusively for cooking , by rural population.

Animal husbandry and extensive agriculture are the main activities in the N.W. and west central areas.

RENEWABLE ENERGY POLICY IN TUNISIA

TUNISIA is an oil producing country and exports part of its production, but the growth of its

local energy consumption limits this part very seriously .

Therefore, in the eighties, the Tunisian government founded the A..M.E. to manage its policy in the field of

Energy Conservation and Renewable Energy.

In this field three aspects are considered :

- The first one is to decrease oil and gas consumption

- The second is to give some comfort and services to rural areas where population is

disseminated and where are missing electricity and roads..., and to reduce the pressure

on towns by limiting rural depopulation.

- The third aspect concerns the best way of using agricultural wastes in energy production

mainly for rural consumption.

The National policy consists in some key steps to agree Renewable Energy programs and to provide

facilities and tax exemptions.

The Key steps are

- the feasability study which includes the calculation of energy potential, the market and social

and economic surveys when necessary.

- the demonstration program and the results analysis

- Technology selection and local industry promotion when demonstration results prove to be

positive.

The facilities and exemption consist :

- in generally financing the feasability study

- in financing the demonstration program partially or exclusively

- in exempting Renewable Energy goods and equipments from duty and some local Taxes

THE ACHIEVED PROGRAMS

A lot of projects are achieved for Research, for demonstration or in industry, using different

sources of Renewable Energy ( photovoltaic, wind, Biomass...)

FOR RESEARCH

1 - Low temperature thermosolar plant of 10 kw;

This plant is running at normal level. But this technology is not efficient enough and should be

discarded. Although it has a didactic role.

2 - water desalination with photovoltaic and wind energy

Osmose inverse and electrodialyse systems were tested using the electricity from a photovoltaic

fiteld ( 4 kw) and from two wind generators (4,5 and Ikw).

the technical results are positive but the cost of the water production is prohibitive and this

experience cannot be generalized.

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In the other hand small green house desalinators, were assembled and could have a good use in rural areas where water is brackich. FOR DEMONSTRATION

1) PHOTOVOLTAIC SYSTEMS

- Household photovoltaic electrification

. HAMMAM-BIADHA village

a photovoltaic plant of 29 kw supply the Hammam-Biadha village (43 household and utilities). This plant is running normally with more than 95% of disponibility since 1984. Energy storage and installation cost are the weak point of this system. The connection to the grid which is now near the village would be made.

. Rural dispersed houses and schools :

For the dispersed rural houses, autonomous systems are tested for covering the minimal needs of the rural household in two areas, 90 in le KEF and 45 in KAIROUN. AHUNDRUND and FIFTY FIVE (155) schools were also electrified with small photovoltaic systems.

xy PV / \ Collector

\

Regulator

Battery

Compared to the grid connection these systems cost fairly less and solve most of household problems, knowing naturally that the grid service is much better.

Load KWh/dag

0 1 2 3 4 5 6 7 8 9 10 20 25

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Photovoltaic water pumping :

Only two units where installed for irrigation, the results are mitigated because of the water needs

exceeds pumping capacity.

Another program is now, underway it concern the installation of fifteen (15) photovoltaic pumps on

surface wells for drinking water destined to rural population.

2) WIND SYSTEMS

Water pumping

Widely diffused, then left off when Diesel Engine became popular, there's now new attempt to

repromote this technology in the agricultural sector, but The cost of equipment slows this action down.

Wind generator

In this field, two experiments where made the first one consisted in connecting two units (12,5

and 10 kw) to the grid. Because of the limited number of the units and of the problems occasioned by

some electronic and mechanic parts, the results of the experience are not very significant.

The second one is the electrification of Jabouza village with two wind generators (2 X 10) which supply in

electricity seventy two (72) house holds.

Some mechanic and electronic problems appeared, but in general, the energy produced by the two

engines covered about 90%of the population needs, the cost and the energy storage are the weak points

of this system

3) BIOMASS

In this field only two subjects are of some interest to date ; the Biogaz production and the

combustion amelioration of rural stoves using wood

. Biogaz

In the North-west about thirty thousand (30 000) little cattle breeders have more than four animals.

The general layout of rural homes including cowsheds and the household needs in energy for lighting and

cooking compared to the biogaz production from four animal dung showed that it is possible to promote

Biogaz production in this region.

Forty Biogaz digestors were constructed for demonstration

The chineese model was chosen and adapted to local conditions. They have 16 m3 and 20 m3 of capacity

and produce between 2 m3 of gaz in winter and 2,7 m3 in summer

Cooking Lighting Refr igerat ion

— U E 2 J Bedrooms

Nbnure EED Kitchen

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Encouraging results and a very good acceptance by population are noted. The generalization of the

systems can be made in puttingon an adequate financing scheme.

.Wood stoves

Wood is the main combustible utilized in rural areas for cooking (mainly the bread}:

80 % of the consumption.)

The goal of this project was to reduce wood consumption by improving stoves efficiency and then to

protect forest cover.

Laboratory tests were made on different models, they showed that some models can save 50 % to 60% of

wood consumption, without a great price increase, while preserving taditional cooking methods.

If the prototype is generalized a hundred thousand tons of wood could be saved.

4) GEOTHERMICS

There are in the south of Tunisia a lot of hot water sources which are utilized for irrigation and

require cooling equipments.

Demonstration was made sucessfuliy for heating greenhouses with geothermol water and now a great

program with hundreds of hectors is launched in the south.

5) SOLAR WATER HEATING AND MECHANICAL WIND PUMPS

It's noteworthy that these equipments are being commercialized since 1985. They are

manufactured in Tunisia for both local use and export.

PROGRAMMATION PLANNED :

The AME activity will finalise some of the demonstration projects witch are mature for application

and start others for demonstration, in particular :

. Extenseve use of small photovoltaic systems in rural areas for houses, schools and utilities

. Installation of a wind farm (5IMW), the feasibility study shows that it is economically

acceptable

. Scheduling plantation of quick-growing trees which will provide wood for energy production.

. generalization of biogaz digestors

. research on other Renewable energies like solar ponds, bioclimatic construction

. feasibility study on high temperature solar plant

. solar drying of land products

. Low and high temperature geothermic potential study in the north of the country and

possibilities of applications.

. Energie conversion of urban wastes.

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