Introduction and context: global biomass resources - Biomass as Energy Source: Resources, Systems and Applications - page 29

the different income group countries. In the last column, we also see the average cereal production
for the different income group countries year 2009.
We should then also notice that the amount of straw is approximately the same as the grain that
is harvested. Therefore, the total biomass production that can be utilized in high income countries
then is approximately 11 tonne/ha per y. In forest areas we can assume that the official production
of approximately 2 tonne DS/ha per y in reality is at least 3 tonne DS/ha per y. In arable land,
we can assume slightly lower productivity and approximately 1.5-2 tonne DS/ha per y can be
reasonable figures to use. We also assume that the heating value is 5.4 MWh/tonne DS, which
is a reasonable value. If we take the official figures of land area for each group and multiply the
cereal production in each group multiplied with 2 and summarize this with the total forest area
times 3 t/ha per y and arable land multiplied with 2 t/ha per y, and multiply with 5.4MWh/tonne,
we obtain:

• agriculture including straw 187,000TWh/y;

• forests 65,000TWh/y;

• arable 19,000TWh/y.

In total this adds up to 270,000TWh/y as higher heating value of all the biomass produced
on land. This can be compared to the total energy use of approximately 150,000TWh/y globally.
From this, we can conclude that there is enough energy for the global population if we use the
energy in a good way. This means to first use wood for e.g. buildings, and then later use the waste
wood for energy purposes.
It is also important to have a sustainable farming and forestry that utilizes all resources in an
effective way. Nutrient for example can be distributed in open soil during autumn or in growing
crops during spring/summer. The total effect will be that in the first case we will get a lot of the
nutrients coming out as leachate into waters or emissions to the air. In the second way, most of
the nutrients will go into the crops instead.

1.8 QUESTIONS FOR DISCUSSION

• How should we use the available biomass resources without causing long-term problems to
sustain the production?
• Why is so little of the produced biomass actual utilized in an efficient way?
•

Who has the rights to the biomass? Are market forces enough to develop the biomass market?

• Is it ethical to use biomass as fuel if the same biomass also can be used as food?

• Discuss the competition for biomass between industries like pulp and paper, chemical

companies and power plants. Should some interest be more important than the other?

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