Uncover the potential of woody biomass in helping to reach clean energy goals around the world.

Namibia’s savanna ecosystem witnesses the expansion and densification of shrubs, a phenomenon globally known as woody plant encroachment. This is attributed to various factors, including overgrazing,  excluding larger mammals and browsers as well as wildfire suppression. Climate change is an accelerating factor, as atmospheric carbon dioxide (CO2) fosters woody vegetation growth. 

Increasing shrub thickening leads to reduced land productivity, triggers a decline in biodiversity, and hampers groundwater recharge. 

With already 45 million hectares of rangeland affected, this is a growing problem for rural communities. Namibia strategically promotes value addition as an economic incentive for sustainable bush control. 

This includes energetic utilisation, biochar, animal fodder and construction material. 

The Namibian biomass sector provides employment for more than 12 000 workers, and allows farmers to diversify their income. 

The approach has become pivotal in Namibia’s efforts of climate change adaptation and ecosystem restoration. 

In the United States (US), approximately 2% of total energy consumption in 2021 was from woody biomass, such as wood chips, scraps and bark. 

The utilisation of woody biomass for electricity-generation is only projected to increase in the coming years, with the US Department of Energy predicting it will increase to 218 billion kilowatts per hour (kWh) by 2030. 

As organic matter derived from trees, woody biomass is the by-product of natural disasters, forest management and restoration as well as hazardous fuel reduction treatments. 

It encompasses limbs, needles, leaves and other woody plant parts grown in forests, woodlands or rangelands. 

Often classified into construction scrap wood, sawmill residues and forest residues, the most common sources of woody biomass include removal of dead or dying trees, forest management harvesting, timber harvesting and logging residues like branches and undersized trees, wood manufacturing residues like bark and sawdust, wood debris from discarded shipping materials, construction as well as tree removal and dedicated tree plantations for woody biomass. Public and private forest owners and managers remove large amounts of woody biomass each year to thin the forests to prevent wildfire, remove diseased trees and improve the health of the forest.

Woody biomass is also a product of natural disasters like hurricanes and tornadoes as well as urban beautification activities, such as power line clearing and tree removal. Unfortunately, most woody biomass is currently burned, left to decay or taken to landfills, instead of being productively used for activities such as clean energy. Instead of being left to decay in landfills, woody biomass could be used to make small wood products, heat, fuel or electrical energy as well as other useful products like mulch. 

The benefits of woody biomass use include lower energy required to produce products from it compared to non-wood materials like steel non-food and organic material, so it will not compete with growing food .

It reduces wildfire hazards when removed from forest, it is a renewable resource, and it emits low amounts of CO2 when used to produce energy.

 Potential challenges include limited availability; it is expensive to harvest, transport and store; it has lower energy density than fossil fuels; it is technically difficult to utilise in chemical and energy processing, and there is competition with higher-quality wood for traditional wood products. 

Woody biomass is also a renewable energy source. 

It can be especially beneficial for clean energy initiatives when used efficiently and when sustainable forest management practices are applied. 

There is already existing technology to directly produce heat energy from wood biomass and produce intermediate biofuels designed to be stored and moved in long distances. 

To heat energy, woody biomass can also produce electrical energy and biofuels like sustainable aviation fuel. 

Although woody biomass can be used for energy production, there are contrasting findings in scientific studies on its effects on the climate due to the wide variety of bioenergy systems, and the differences in assessment methods. 

Despite the variety of findings on the positive effects that using woody biomass as an energy source has on the climate, the main issues in its utilisation potential are availability. Although there is enough of a supply of woody biomass resources to cover a large portion of the world’s primary energy consumption by 2050, these resources have many alternate uses, and their accessibility is limited, so it often pales in comparison to other forms of clean energy. 

By combining high-tech innovative tools, knowledgeable people, and streamlined processes, Namibian people can evolve alongside their clients to establish routines that generate virtuous cycles of stainable growth like better managing their forest waste to benefit from the production of woody biomass. Echoing these sentiments, Nelson Lucas noted that “Namibia, with its vast landscapes and unique biodiversity, is a prime example of a region that can benefit immensely from biomass energy. 

By harnessing the power of organic materials, we can reduce waste, generate clean energy and promote rural development’’.

*Dr Moses Amweelo is a former minister of works, transport and communication. He is currently a lecturer at IUM and Unam on a part-time basis.