Solar Energy Perspectives - IEA

Chapter 5: Industry and transport
Chapter 5
Industry and transport
The progress of efficient electricity-based techniques in industry and transport may become
the main vehicle for introducing solar energy more broadly in industry. Some companies may
recognise the benefits of producing solar electricity at or near their industrial facilities.
Prospects for direct use of low-temperature solar heat are considerable in the food industry,
and noteworthy in several other industries. Use of high-temperature heat from concentrating
solar rays may warrant further investigation, beyond possibilities in desalination for fresh
water production.
Industrial electricity
Manufacturing industry accounts for approximately one-third of total energy use
worldwide. Electricity constitutes just over one quarter of this energy; fossil fuels and
biomass (for about 8% to total final energy in 2007) provide the rest, mainly used as
process heat but also for self-generation of electricity, including co-generation of heat and
power.
As in other consuming sectors, if a larger share of grid electricity comes from renewables
in general and solar energy in particular (as seen in Chapter 3), so will the electricity
consumed in industry. One way to get more solar and renewables in the industrial energy
mix is thus to develop efficient uses of electricity – with a progressively growing solar and
renewable share – to displace fossil fuel uses. Many technologies are now available that
can replace fossil fuels for a great diversity of industrial processes. Examples include freeze
concentration instead of the thermal process of evaporation; dielectric heating (radio
frequency and microwave heating) for drying; polymerisation; and powder coatings using
infra-red ovens for curing instead of solvent-based coatings and conventional convection
ovens (Eurelectric, 2004). Most often, converting a process to electricity improves process
control and productivity. In many cases, electric-heating applications are more energyefficient
than their alternatives, especially at high temperatures. Optimal efficiency of an
electric furnace can reach up to 95%, whilst the equivalent for a gas furnace is only 40%
to 80%.
The use of electrochemical processes to produce iron ore, known as electro-winning, is
currently in an early R&D phase. Aluminium is produced entirely by electro-winning and the
approach is also used in the production of lead, copper, gold, silver, zinc, chromium, cobalt,
manganese, and the rare-earth and alkali metals. If a technological breakthrough were to
make the production of iron by electro-winning feasible, renewable energy could more easily
substitute for fossil fuels in this major application.
Indeed the share of electricity in industrial energy consumption is expected to increase
from one-fourth to one-third by 2050 (IEA, 2009a). The climate-friendly BLUE Map
Scenarios are little different from the Baseline Scenario in this respect, with shares of
electricity in industrial productivity variants shown as “high” (37%) or “low” (35%)
(Figure 5.1).
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© OECD/IEA, 2011