Namibia to start bush-to-electricity project from invader-bush

Aug 30, 2007 02:00 AM

A new way of combating bush encroachment and restoring Namibia's savannah landscapes will start in September when a N$ 14 mm project to set up an independent power plant fed with invader bush will kick off. The “bush-to-electricity” project is run by the Desert Research Foundation of Namibia (DRFN), an energy expert at the organisation has announced.
"Other partners are the Namibia National Farmers' Union (NNFU) and the Namibia Agricultural Union (NAU)," Claus-Peter Hager told a meeting of charcoal producers at Otjiwarongo. "The Ministries of Environment and Tourism and Agriculture were also consulted. Funding of N$ 14 mm from the European Union over the next 24 months has been secured," Hager said.

Vast tracts of farmland cannot be used for farming because of encroachment by hardy shrubs and trees, generically known as invader bush. Studies indicate that about 26 mm hectares of agricultural land are infested, which is preventing the growth of useful grass species. It also results in soil compaction in the bush-encroached areas.
This has reduced Namibia's carrying capacity for livestock, resulting in reduced cattle numbers over the past 50 years -- from 2,5 mm in the commercial farming areas down to some 800,000 head of cattle. According to experts, the reduced availability of land for grazing causes economic losses of N$ 700 mm in the agricultural sector every year.

Another worrying factor is that the extensive root network -- up to 40 metres long -- of some invader bush species robs the soil of moisture. Soil also gets compacted, which prevents rain water from penetrating the soil and replenishing the underground water table. Hager told the meeting that usually, underground water was recharged with just 6 % of rain received.
"In bush-infested areas it is less than 1 %." Another adverse effect is that invader bush increases water run-off and erosion.

The project will be located in one of the areas with the highest density of invader bush -- around the north-central towns of Tsumeb, Otavi and Grootfontein. It wants to use farms that already harvest invader bush for charcoal production. The proximity of the areas to power lines, where the generated power can be fed into the national electricity grid, will also play a role.
"The exact site for the power station has not been chosen yet," Hager said. Between one and four hectares of harvested invader bush can generate enough electricity to power one household for a year.

Fed into the power plant, one hectare of bush can generate between 0,5 MW and 2,5 MW of electricity. The aim is to clear 1,5 mm hectares of bush each year. A wood gassifier extracts gas from the wood at high temperatures, which is then transferred to a generator where almost 100 % combustion takes place. Thanks to new technology, virtually no carbon dioxide will be emitted. According to DRFN, up to 3,500 GWh of electricity could be generated by this independent power producer (IPP).
"The idea is not to totally eradicate invader bush species, but to thin itout," Hager said. "The sustainable use of this energy source, which grows back, is the aim.”
“We call it energy farming," he added.

Namibia's electricity consumption is about 400 MW. Another plan is to create small and medium enterprises (SMEs) to decentralise electricity supply and to involve more commercial and communal farmers and other people living in rural areas, where bush encroachment is found, to become suppliers of invader bush for small electricity plants in future.
Namibia already makes use of invader bush to produce charcoal. About 45,000 tons of charcoal a year is produced, providing welcome additional income for farmers.

At the meeting, geo-hydrologist Frank Bockmuehl said bush encroachment had reached such alarming proportions, that "our rivers flow far less than two, three decades ago or in some cases don't flow at all any more".
"On our farm in the Outjo area, my grandmother used a lovely spring to water her extensive vegetable garden. She regularly supplied the school hostels in town with the vegetables. The spring dried up 18 years ago; the water table on the farm had dropped by 10 metres."

He then started a debushing exercise and cleared 300 ha recently.
"To my great surprise and joy, the water at the fountain came back a few months ago and has kept a steady flow," the geo-hydrologist said. "The water table rose."

Source / The Namibian
Market Research

The International Affairs Institute (IAI) and OCP Policy Center recently launched a new book: The Future of Natural Gas. Markets and Geopolitics.

Cover_242-width

The book is an in-depth analysis of some of the fastest moving gas markets, attempting to define the trends of a resource that will have a decisive role in shaping the global economy and modelling the geopolitical dynamics in the next decades.

Some of the top scholars in the energy sector have contributed to this volume such as Gonzalo Escribano, Director Energy and Climate Change Programme, Elcano Royal Institute, Madrid, Coby van der Linde, Director Clingendael International Energy Programme, The Hague and Houda Ben Jannet Allal, General Director Observatoire Méditerranéen de l’Energie (OME), Paris.

For only €32.50 you have your own copy of The Future of Natural Gas. Markets and Geopolitics. Click here to order now!


 

Upcoming Conferences
« September 2017 »
September
MoTuWeThFrSaSu
1 2 3
4 5 6 7 8 9 10
11 12 13 14 15 16 17
18 19 20 21 22 23 24
25 26 27 28 29 30

Register to announce Your Event

View All Events