Solar Energy Perspectives - IEA

Solar Energy Perspectives: Industry and transport
But charcoal could be produced from a number of biomass sources, not only trees.
Furthermore, the solid biomass to be used in industry, whether in the sectors identified by
Taibi et al. or in other sectors, such as iron and steel, could be enhanced by using solar
energy (apart from through photosynthesis). The transformation of biomass, in industry as
well as for transportation, requires large amounts of energy, mostly heat, which is usually
provided by burning part of the feedstock. Given possible limitations on the global biomass
feedstock and its relatively high footprint, using solar heat at various temperature levels to
process the raw biomass could possibly allow a further extension of its uses.
Solar heat
Process heat is the major energy consumer in the energy sector. Figure 5.4 illustrates the
repartition of industrial heat demand in greater Europe (32 countries) by temperature
bands and by industry branches. Low-temperature heat is 30%, high-temperature heat
43% and medium-temperature heat 27%. Other studies suggest that about two-thirds of
the heat in the 100°C to 400°C range is used in industry at temperature levels lower
than 200°C.
Figure 5.4 Estimated industrial heat demand by temperature range in Europe, 2003
High,
over 400 0 C
Medium,
100 0 C to 400 0 C
Low,
below 100 0 C
PJ
2 500
2 000
1 500
1 000
500
Source: Werner, 2005-2006.
Key point
0
Basic
metals
Chemical
Non-metallic
minerals
Transport
equipment
Figure 5.4
Machinery
Mining and
quarrying
Food and
tabacco
Pulp and
paper
Others
More than half process heat is of low and medium temperatures.
Other studies performed in various countries differentiate low- and medium-temperature heat
as above and below 160°C for selected industry sectors. This is very helpful for a low-carbon
process, as process heat below 160°C can be provided by solar thermal collectors in most
cases, though the cost-effectiveness obviously depends on the global (direct and diffuse) solar
resource. The most significant current application areas are in the food and beverage
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