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Table 3. Bioenergy Production Potentials for Selected Biomass Types, 2050

Biomass Type

Agricultural Residues

Organic Wastes

Animal Dung

Forest Residues

Energy Crop Farming (current agricultural lands)

Energy Crop Farming (marginal lands) Biomaterials

Total

Bioenergy Potential (exajoules)

15–70

5–50+b

5–55 (or possibly 0)

30–150 (or possibly 0)

0–700 (100–300 is more average)

60–150 (or possibly 0)

Minus 40– 150 (or possibly 0)

40–1,100 (250–500 is more average)

Main Assumptions and Remarks

  • Based on estimates from various studies.

  • Potential depends on yield/product ratios, total

agricultural land area, type of production system. Extensive production systems require leaving of residues to maintain soil fertility; intensive systems allow for higher rates of residue energy use.

  • Based on estimates from various studies.

  • Includes the organic fraction of MSW and waste wood.

  • Strongly dependent on economic development and

consumption, and as well as use for biomaterials.

  • Higher values possible by more intensive biomaterials

use.

  • Use of dried dung.

  • Low range value based on current global use; high

value reflects technical potential.

  • Utilization (collection) over longer term is uncertain.

  • Figures include processing residues.

  • Part is natural forest (reserves).

  • The (sustainable) energy potential of world forests is

unclear.

  • Low range value based on sustainable forest

management; high value reflects technical potential.

  • Potential land availability of 0–4 global hectares (Gha),

though 1–2 is more average.

  • Based on productivity of 8–12 dry tonne/ha/yra (higher

yields are likely with better soil quality).

  • If adaptation of intensive agricultural production

systems is not feasible, bioenergy supply could be zero.

  • Potential maximum land area of 1.7 Gha.

  • Low productivity is 2–5 dry tonne/ha/yr.a

  • Bioenergy supply could be low or zero due to poor

economics or competition with food production.

  • These provide an additional claim on biomass

supplies.

  • Land area required to meet additional global demand

is 0.2– 0.8 Gha

  • Average productivity is 5 dry tonnes/ha/yr.a

  • Supply would come from energy crop farming if forests

are unable to meet this demand.

  • Pessimistic scenario assumes no land for energy

farming, only use of residues; optimistic scenario assumes intensive agriculture on better quality soils.

  • More average range = most realistic in a world aiming

for large-scale bioenergy use.

Notes: (a) heating value: 19 GJ/tonne dry matter; (b) the energy supply of biomaterials ending up as waste can vary between 20–55 EJ (or 1,100-2,900 million tonnes of dry matter per year). Biomass lost during conversion, such as charcoal, is logically excluded from this range. This range excludes cascading and does not take into account the time delay between production of the material and its ‘release’ as (organic) waste. Source: Andre Faaij, Copernicus Institute, Utrecht University, report submitted to Worldwatch Institute, 17 January 2005.

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