Key challenges for science and engineering in the 21st century
Population increase > Increased energy requirements > Increased land use > Climate change > Reduced availability of fresh water
Climate Change
Mean global temperature increases
- Melting glaciers > Sea level rises
Increased CO2 concentration in the atmosphere
Increase in global precipitation -More heavy rainfall
Increase in drought intensity, frequency and duration- More frequent extreme weather events
Increasing land use
In the past, demand growth has been met through yield growth. But the strong demand growth ahead will create a need for substaintial acreage expansion
Increased demand for energy
Total world energy demands are predicted to increased by approximately 50% by 2030
China is the main driver of increasing energy demand in the current decade, but India takes over in the 2020s as the principal source of growth
Rising oil output from North America and Brazil - helping quench global oil thirst over the next decade
Middle East will continue to be a key source of oil supply growth from the mid 2020s.
% growth in global energy demand will be met by low carbon energy sources and in some regions by _______
~40% of
rapid expansion of_________ raises fundamental questions about the design of power markets and their ability to ensure ___________
rapid expansion of wind and solar PV
to ensure adequate investment and long term reliability.
A critical element of economic well being and industrial competitiveness in many countries is
energy availability and affordability
[large variations in energy prices are reported to exist through 2035]
energy efficiency is set to remain untapped in 2035 unless ___________
unless market barriers can be overcome
Energy related carbon dioxide emissions are projected to (change) by ? % to 2035,
> a long term average temperature change of ? °C
which is different to the internationally agreed ? °C climate target.
rise by 20% to 2035
a long term average temperature increase of 3.6 °C
which is above the internationally agreed 2 °C climate target.
new types of energy resources
e.g. light tight oil and ultra deepwater fields.
Reduced availability of fresh water
1 billion people lack access to drinking water.
2 billion people lack adequate sanitation.
By 2050 more than half the world will face water shortages.
Food, feed fuel deman trend
Food demand is stable, feed demand is rising and fuel demand is exploding
Wealth increases demand
Increased wealth leads to more grain being indirectly consumed through animal products
More demand for meat with increasing income > Increases meat prices > Increase livestock production > Increase grain feed prices > Divert grain from food to feed > Increase food prices
Feed demand
- Emerging markets
- Global consumption increase for meat almost double
- A majority of meat production is now located in countries that practice and use soybean meal feed
- Feed demand has increased substantially given the rise in consumption of protein- intensive foods
Poverty alleviation
= 1.1 bn people are living with low income per day, mainly under nutrition and hunger
Feed efficiency
Feed to meat ratio
Grains required per g of animal weight gain :
Cattle (8.3) hog (3.1) Chicken (2.0) Fish (1.5)
Grains required per kcal of energy pervision to human:
Beef (2.99) Pork (0.82) Poultry (0.94) Fish (1.29)
Food production
Corn yield:
High yielding country yield 7.5 tonnes/ha
Low yielding country yield 2.8 tonnes/ha
Additional 200 Million tonnes/year of corn and wheat estimated to be needed by 2017
Increasing low yielding countries to global average would produce an additional 100 Million tonnes/year
Reduction of waste is crucial
Current crop loss due to pests and disease worldwide (Oerke, 2006)
- Potaotes -40%
- Rice -37%
- Maze -32%
- Wheat -28%
Total worldwide crop losses are estimated to be in excess of 40% (Yudelman et al 1998)
Human food requirements
10 essential amino acids that make up proteins
Fatty acid linoleic acid (omega 3)
Vitamins
10 essential amino acids
leucine, isoleucine, lysine, methionine, phenylalanine, threonine, tryptophan, valine and for infants (arginine and histidine)
Fatty acid linoleic acid (omega 3) abundant in
plant oils, nuts and fish oils
Essential vitamins
Vitamins A, B1, B2, B3, B6, B12, C, D, E, K, pantothenic acid, biotin, and folic acid.
Plant products generally lack:
tryptophan methionine lysine
Animal feed used in developed countries
Animal feed used in developing countries
Mixed plant sources /Animal sources
Maize
Increasing methionine in feed
Loss of methionine through conversion of plant to microbial protein in the rumen
Fuel production
Increase in ethanol production over the years, mostly from grain feedstock in US/China/ EU/ Canada & sugarcane in Brazil
(USDA Agricultural Projections)
World fuel ethnol production 2007
USA ~50%
Brazil ~ 39%
EU ~4%
China ~3.7%
Ethanol production is driven by
increased exponentially driven by crude oil prices
Crossing $55 per barrel made it competitive to substitute petrol with gasohol (petrol blended with ethanol).
gasohol
petrol blended with ethanol
Increasing biofuel output
output expected to more than double in next few decades.
Will require a dramatic increase in the land used given the preference for indigenous feed stocks
Limiting biofuel production
In the EU:
By 2020 renewable energy sources must account for at least 10% of transport fuel use.
In 2013 the European Parliament approved a proposal to limit the amount of food crop based biofuels that can be counted towards renewable energy targets to 6%.
Prefer second generation biofuels from non-food feedstock – waste, straw, algae.
emphesis on 2nd generation biofuels because
they are presumed to emit substantially less greenhouse gases than fossil fuels and do not directly interfere with global food production.
Perferred second generation biofuels in EU
from non-food feedstock – waste, straw, algae.
By 2020 renewable energy sources must account for % of which use
at least 10% of transport fuel use.
research is being done into using _____ to produce ethanol
the problem
straw
the plant matter requires a considerable energy input to break it down
but don’t want plant with broken stem before harvest
problem of biofuel
diverting farm production away from food crops, thus potentially driving up food prices.
need a clear and stable energy-policy framework or else power-sector investment will dry up
Current emissions target
2020 - to reduce carbon-dioxide emissions to 20% below 1990 levels.
2050 - aim for CO2 emissions at least 80% below 1990 levels, as well as nearly eliminate emissions from the electricity sector.
2030 - reduce greenhouse gases, boosting renewable energy, and cutting total energy consumption
Controversy converting ________ to produce crop-based biofuels as they emit more CO2 than displacing fossil fuels
because
rainforests, peatlands, savannas or grasslands
- Carbon debt resulting from habitat conversion
- Number of years after conversion to biofuel prodction required for cumulative biofuel GHG reductions, relative to the fossil fuels they displace, to repay the biofuel carbon debt.
Next generation biofuels offer
significant potential e.g. from appropriate wastes, residues and other technology
Advantages of Algae as feedstocks for biofuels
- Synthesise and accumulate large quantities of lipids.
- High growth rates.
- Tolerate areas not suitable for conventional agriculture.
- Can be grown in culture vessels all year round.
- Produce 10x more biomass than terrestrial plants on an area basis.
UK low carbon energy production
- Carbon capture and storage
- marine technologies
- offshire wind