Environmental Engineering Reference
In-Depth Information
highest rates of growth in GHG emissions in any sector over the last ten years (20%
global CO
2
emissions, 25% UK emissions), with a predictable 80% higher energy
use and carbon emissions than now by 2030 [2].
Oil is the world's primary source of energy and chemicals with a current demand
of about 12 million tonnes per day (84 million barrels a day) [3] and a projec-
tion to increase to 16 million tonnes per day (116 million barrels a day) by 2030.
While a 30% of the global oil consumption accounts for transport, a striking 60%
of the rising demand expected for 2030 corresponds to transport [4]. With the trans-
port sector expanding in the US and Europe and specially developing in the newly
industrialised and emerging economies of China and India, these values can easily
be underestimated. The availability of conventional oil is again becoming geograph-
ically restricted and a general agreement now is that the era of cheap and secure
oil (cheap energy) is over [5, 6]. Several alternatives are currently been explored,
including a range of carbon free and renewable sources (photovoltaics, wind and
nuclear power, hydrogen), in an attempt to replace natural gas, coal and oil in the
electricity generation sector. However there is not such equivalent in transportation
yet, since fuel cells, electric/hydrids and natural gas based cars are still a long way
from becoming mainstream vehicles.
A short and medium term alternative is needed. Crop-based fuels denoted as bio-
fuels including biodiesel and bioethanol, emerged as a real alternative to the use of
gasoline and conventional diesel in transportation. There has been a relatively high
acceptance from general public, governments, producers and part of the agricultural
sectors in promoting the expansion of biofuels in our society in an attempt to switch
from the petrol-based industry we have been relying on for the last 50+ years to a
biobased industry and society that can guarantee a more secure energy supply. An
exponential increase in the consumption of these biofuels has taken place in the last
few years (Fig. 8.1).
Fig. 8.1
Biofuels consumption (1991-2006) in the EU27
Source: REFUEL, IEA, Eurovserv' ER. Reproduced with permission of Marc Londo.
