An Introduction to Biomass Harvesting

Biomass harvesting and collection is an important step involving gathering and removal of the biomass from field which is dependent on the state of biomass, i.e. grass, woody, or crop residue. The moisture content and the end use of biomass also affect the way biomass is collected. For crop residues, the operations should be organized in sync with the grain harvest as it occupies the centrestage in farming process.


All of other operations such as residue management and collection take place after so-called grain is in the bin. On the other hand, the harvest and collection dedicated crops (grass and woody) can be staged for recovery of the biomass only. In agricultural processing, straw is the stems and leaves of small cereals while chaff is husks and glumes of seed removed during threshing.

Modern combine-harvesters generally deliver straw and chaff together; other threshing equipment separates them. Stover is the field residues of large cereals, such as maize and sorghum. Stubble is the stumps of the reaped crop, left in the field after harvest. Agro-industrial wastes are by-products of the primary processing of crops, including bran, milling offal, press-cakes and molasses. Bran from on-farm husking of cereals and pulses are fed to livestock or foraged directly by backyard fowls.

The proportion of straw, or stover, to grain varies from crop to crop and according to yield level (very low grain yields have a higher proportion of straw) but is usually slightly over half the harvestable biomass. The height of cutting will also affect how much stubble is left in the field: many combine-harvested crops are cut high; crops on small-scale farms where straw is scarce may be cut at ground level by sickle or uprooted by hand.

Modern combine-harvesters generally deliver straw and chaff together

Collection involves operations pertaining to gathering, packaging, and transporting biomass to a nearby site for temporary storage. The amount of a biomass resource that can be collected at a given time depends on a variety of factors. In case of agricultural residues, these considerations include the type and sequence of collection operations, the efficiency of collection equipment, tillage and crop management practices, and environmental restrictions, such as the need to control erosion, maintain soil productivity, and maintain soil carbon levels.

Energy from Biomass Wastes in MENA

The high volatility in oil prices in the recent past and the resulting turbulence in energy markets has compelled many MENA countries, especially the non-oil producers, to look for alternate sources of energy, for both economic and environmental reasons. The significance of renewable energy has been increasing rapidly worldwide due to its potential to mitigate climate change, to foster sustainable development in poor communities, and augment energy security and supply.

The MENA region is well-poised for biomass waste-to-energy development, with its rich feedstock base in the form of municipal solid wastes, crop residues and agro-industrial wastes. The high rate of population growth, urbanization and economic expansion in the Middle East is not only accelerating consumption rates but also accelerating the generation of a wide variety of waste.

Bahrain, Saudi Arabia, UAE, Qatar and Kuwait rank in the top-ten worldwide in terms of per capita waste generation. The gross urban waste generation quantity from Arab countries is estimated at more than 80 million tons annually. Open dumping is the most prevalent mode of municipal solid waste disposal in most countries.


Many Middle East nations lack legislative framework and regulations to deal with urban wastes.

Biomass wastes-to-energy technologies hold the potential to create renewable energy from biomass waste in the MENA region. Besides recovery of substantial energy, these technologies can lead to a substantial reduction in the overall waste quantities requiring final disposal, which can be better managed for safe disposal in a controlled manner. Energy from biomass wastes can contribute substantially to GHG mitigation in the Middle East through both reductions of fossil carbon emissions and long-term storage of carbon in biomass wastes.

Biomass waste-to-energy systems options offer significant, cost-effective and perpetual opportunities for greenhouse gas emission reductions. Additional benefits offered are employment creation in rural areas, reduction of a country’s dependency on imported energy carriers (and the related improvement of the balance of trade), better waste control, and potentially benign effects with regard to biodiversity, desertification, recreational value, etc.

In summary, waste-to-energy can significantly contribute to sustainable development both in developed and less developed countries. Waste-to-energy is not only a solution to reduce the volume of waste that is and provide a supplemental energy source, but also yields a number of social benefits that cannot easily be quantified.

Biomass wastes in MENA can be efficiently converted into energy and fuels by biochemical and thermal conversion technologies, such as anaerobic digestion, gasification and pyrolysis. Waste-to-energy technologies hold the potential to create renewable energy from waste matter.

The implementation of waste-to-energy technologies as a method for safe disposal of solid and liquid biomass wastes, and as an attractive option to generate heat, power and fuels, can significantly reduce environmental impacts of wastes in the MENA region. In fact, energy recovery from MSW is rapidly gaining worldwide recognition as the fourth ‘R’ in sustainable waste management system – Reuse, Reduce, Recycle and Recover.

A transition from conventional waste management system to one based on sustainable practices is necessary to address environmental concerns and to foster sustainable development in the region.

Biomass Resources in Malaysia

Malaysia is gifted with conventional energy resources such as oil and gas as well as renewables like hydro, biomass and solar energy. As far as biomass resources in Malaysia are concerned, Malaysia has tremendous agricultural biomass and wood waste resources available for immediate exploitation. This energy potential of biomass resource is yet to be exploited properly in the country.

Taking into account the growing energy consumption and domestic energy supply constraints, Malaysia has set sustainable development and diversification of energy sources, as the economy’s main energy policy goals. The Five-Fuel Strategy recognises renewable energy resources as the economy’s fifth fuel after oil, coal, natural gas and hydro. Being a major agricultural commodity producer in the region Malaysia is well positioned amongst the ASEAN countries to promote the use of biomass as a source of renewable energy.

Major Biomass Resources in Malaysia

  • Agricultural crops e.g. sugarcane, cassava, corn
  • Agricultural residues e.g. rice straw, cassava rhizome, corncobs
  • Woody biomass e.g. fast-growing trees, wood waste from wood mill, sawdust
  • Agro-Industrial wastes e.g. rice husks from rice mills, molasses and bagasse from sugar refineries, residues from palm oil mills
  • Municipal solid waste
  • Animal manure and poultry litter

Palm Oil Biomass

Malaysia is the world’s leading exporter of palm oil, exporting more than 19.9 million tonnes of palm oil in 2017. The extraction of palm oil from palm fruits results in a large quantity of waste in the form of palm kernel shells, empty fruit bunches and mesocarp fibres. In 2011, more than 80 million tons of oil palm biomass was generated across the country.

13MW biomass power plant at a palm oil mill in Sandakan, Sabah (Malaysia)

Processing crude palm oil generates a foul-smelling effluent, called Palm Oil Mill Effluent or POME, which when treated using anaerobic processes, releases biogas. Around 58 million tons of POME is produced in Malaysia annually, which has the potential to produce an estimated 15 billion m3 of biogas.

Rice Husk

Rice husk is another important agricultural biomass resource in Malaysia with very good energy potential for biomass cogeneration. An example of its attractive energy potential is biomass power plant in the state of Perlis which uses rice husk as the main source of fuel and generates 10 MW power to meet the requirements of 30,000 households.

Municipal Solid Wastes

The per capita generation of solid waste in Malaysia varies from 0.45 to 1.44kg/day depending on the economic status of an area. Malaysian solid wastes contain very high organic waste and consequently high moisture content and bulk density of above 200kg/m3. The high rate of population growth is the country has resulted in rapid increase in solid waste generation which is usually dumped in landfills.


Biomass resources have long been identified as sustainable source of renewable energy particularly in countries where there is abundant agricultural activities. Intensive use of biomass as renewable energy source in Malaysia could reduce dependency on fossil fuels and significant advantage lies in reduction of net carbon dioxide emissions to atmosphere leading to less greenhouse effect. However, increased competitiveness will require large-scale investment and advances in technologies for converting this biomass to energy efficiently and economically.