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Frequently Asked Questions (FAQ)

  • What does bush encroachment mean for farmers and wildlife and how does Acacia Energy help solve the issue?
    Less soil moisture also makes it harder for other vegetation, such as grass, to flourish, reducing the natural grazing availability of the land. As a result of this fierce competition for water, productivity across this land is severely impacted, whereby fewer animals can be supported, both in terms of wildlife and livestock. Some species that rely on these grazing animals are especially affected, such as the Cheetah, which need open savannah habitats to survive.
  • Does bush encroachment impact migration of people?
    Yes, with agriculture being the country’s single largest employment sector, and wildlife tourism playing a significant role within the country’s economy, reduced productivity and biodiversity alike is disastrous for rural livelihoods. Bush encroachment reduces economic opportunity in the affected areas. Livestock production capacity has halved, becoming commercially unsustainable and the viability of tourism activity is also heavily impacted as wildlife become scarcer and more difficult to find. This resulting “opportunity desert” forces people out of these areas, in search of livelihoods elsewhere, contributing to rural-urban migration, another of the country’s most dire problems. Acacia’s target is to drive decentralised development, increasing rural opportunities in agriculture, biomass harvesting, tourism, and energy generation.
  • What does bush thinning mean regarding CO2 emissions?
    Bush encroachment is a symptom of climate change, and it also exacerbates it. Contrary to the popular belief that all wood is good for carbon sequestration. In Namibia, research has shown the opposite, whereby bush encroached land has less carbon sequestration potential compared to savannah ecosystems, due to the heavily reduced carbon holding capacity of the soils caused by bush encroachment. This off-sets the benefit of the above ground woody biomass. Furthermore, Acacia Energy’s aim is to switch our clients from fossil fuels (e.g. heavy fuel oil or coal) to renewable bush-biomass, where CO2 emissions go down to zero.
  • What is the alternative to harvesting and using the bush?
    Previously, in desperation, farmers in Namibia poisoned the bush unselectively over large areas, to keep the bush under control. However, this was ecologically devastating, and has had long-lasting impacts, even though it gave some temporary relief to livestock producers, as it allowed grasses to flourish once again. However, in recent times, Namibians have begun to see the bush in a different light. No more is it an economic burden, but more an economic opportunity. Starting with relatively low value uses, such as charcoal production, and evolving to higher value opportunities including animal fodders, building materials, and energy.
  • What is the benefit for a typical Acacia Energy client?
    Acacia Energy takes over the responsibility for energy generation. The client simply pays for the energy and can focus on their core business. Acacia Energy also strives to save costs for their clients, in order to motivate the move away from fossil fuels economically. Acacia Energy provides its clients with renewable energy from sustainably harvested and managed land, allowing them to reduce their CO2 footprint and give them a positive marketing opportunity. Acacia Energy clients do not require any capital investments. Acacia Energy develop, finance, and manage their systems independently of the client. Acacia Energy can achieve this through signing of long-term energy service agreements with clients.
  • Do I qualify for Acacia Energy services?
    Acacia Energy can serve clients with a certain level of energy demand, to ensure that we can offer savings from day one. In certain cases, clusters of off-takers can also be considered, where a centralised system can be used to serve multiple clients. Acacia Energy typically needs to serve one or more clients with base load energy requirements, either power, heat, or cooling. So if you have an energy intensive operation contact us to see how we can help you.
  • What is energy contracting?
    We strongly believe that each company should focus on what it is good at. Our focus is energy generation and delivery. That is why we provide energy services to our clients. Our clients buy Acacia Energy where they need it and in the form they need it in. We do the rest. Acacia Energy focuses on the thermal conversion of bush biomass. Using this thermal energy, we can produce base load power, heat (hot water or steam) and cooling. This means a single Acacia Energy system can provide up to three forms of energy at the same time, to either a single or multiple clients.
  • Is the use of biomass for power generation energy efficient?
    Biomass as a source of energy can be used to cogenerate different energies. These cogeneration systems have very high overall efficiency, as the heat generated can be used to heat water or create steam, it can be used to generate power, and it can be used to generate cooling through heat exchange.
  • Is energy contracting a new business model?
    No, in Europe, biomass energy contracting started approximately 20 years ago, with Germany leading the push. As such, there is vast experience in Germany regarding the operation of biomass power plants for energy contracting purposes. In Namibia, energy contracting has also become common over the last 5-10 years, but it has typically been modelled on solar photovoltaics and not base-load renewable options such as biomass.
  • Why is biomass energy from Acacia Energy considered CO2 neutral?
    When growing, every plant stores CO2. When that plant is burnt or decomposes, exactly the same amount of CO2 gets released to the environment - a CO2-neutral cycle. Acacia Energy uses bush biomass for its energy generation. In our process, the amount of CO2 released into the environment is exactly the same as the amount of CO2 released if the bush dies and decomposes. However, in our case, we use that energy to replace fossil fuels, so at the end of the day, it can even be considered as a CO2 negative activity!
  • What causes bush encroachment?
    Bush encroachment is caused by a mix of different factors, both on a local level and on a climatic scale. Increasing atmospheric CO2 levels have been shown to “fertilize” woody species, giving them competitive advantages over non-woody species like grasses. Additionally, global warming also increases rainfall variability, which is more detrimental to grasses than woody species. Reduced frost also benefits the bush. On the local level, the last 150 years have seen a sustained mismanagement of the savannah system, largely due to a lack of understanding on an ecosystem level. To start, farming practices have led to the suppression of natural fires, in order to protect grazing. However, fires are essential for maintaining healthy grasslands. Farmers also prefer grazing livestock to browsing ones. This puts more pressure on the grasslands. To amplify the problem, fencing the farmland means that the animals cannot migrate to find better grazing, which causes overgrazing. After the sustained and prolonged weakening of the grasses, woody species can flourish – as their natural competitors are under constant pressure. As bushes start to dominate, they enforce the change, as they start outcompeting other vegetation for water, nutrients, and light. Eventually, bush take over, filling the hole in the ecosystem that our human activities have created.
  • Where does bush encroachment happen?
    Bush encroachment can happen anywhere where there is sufficient rainfall to sustain their growth. In Namibia, this usually means areas that receive an average annual rainfall of over 150 mm and under 600 mm per year. Once areas receive under 150 mm per annum, bush struggles to flourish. Over 600 mm per annum, natural woodlands and forests start occurring naturally, whereby dense woody dominance is normal. As Namibia is a semi-arid country, a vast majority of it receives between 150-600 mm. Historically, these areas were natural savannah grasslands, but due to the human activities, these savannah areas are now dominated by woody species. Bush encroachment does not only occur in Namibia. Bush encroachment is occurring across many savannah systems across the world. Southern Africa is estimated to be affected by over 120 million hectares of bush encroachment (i.e. over three times the size of Germany). Bush encroachment is also taking place in Central Africa, South America, Australia, and Cuba.
  • Which bush species cause bush encroachment?
    In Namibia, bush encroachment is caused by native species. In other countries, it can also be caused by alien invasive species. In Namibia, the most common encroacher bush species are; Senegalia mellifera, commonly known as Black Thorn Vachellia reficiens, commonly known as Red Thorn Dichrostachys cinerea, commonly known as Sickle Bush Terminalia sericea, commonly known as Silver Cluster Leaf Colophospermum mopane, commonly known as Mopane Seeing as these are all native species (i.e. naturally occurring), Namibia’s aim is to thin out the bush, to allow for a more balanced ecosystem to be reached. By no means is the idea to eradicate these species from the landscape.
  • How is bush biomass considered sustainable when it is not being re-planted?
    In Namibia, bush is allowed to be harvested, but only on a sustainable basis. This is usually called “bush thinning” and it only allows for the dominant encroacher species to be targeted. Typically, bush thinning involves the removal of 30-60% of the woody biomass on the land, depending on how severe the bush encroachment is. The remaining bush and trees remain, and the removed bush make way for grasses and other vegetation to return. However, over time, bush will start to regrow, and re-encroach these harvested areas. This happens over 15-25 years, depending on the rainfall and species. It is for this reason that bush encroached areas in Namibia can become Forestry Stewardship Council (FSC) certified. While not a forest in a traditional sense, the woody resource can be managed on a sustainable cycle, whereby the harvested wood naturally replenishes itself over a 15-25 year cycle. Currently, over one million hectares of Namibian farmland is FSC certified. In addition to FSC, the Directorate of Forestry, within the Ministry of Environment, Forestry and Tourism of Namibia, also controls the harvesting of woody resources across the country. All harvesting needs a permit from the Namibian government.
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