We are moving into what I see is a period of resource and limitation to our endeavours
our expansions as a species if you like.
So we know that the human population is going to rise from its current 7 billion to about
9 billion by somewhere in the middle of this century and we know that we have to increase
food production by 50% to meet that expansion with the human population.
We know that energy demand is going to research about 50% of its current levels at least as
well and we also know that we are expecting the expansion in freshwater use by about 30%
by then as well.
And all of these things we need to achieve within the constraints of the planet.
Now if you look at what human beings do currently so we currently consume something on the order
of 40% of the primary productivity of the terrestrial biosphere.
So all of the sunlight being fixed in the terrestrial biosphere about 40% of that goes
into human consumption in one way or another.
And we also know, because people have been doing some estimates on this, that the room
for expansion is quite limited so we might be able to get another 10% out of what exists
there.
So increasing food in terms of the area and how much of that primary productivity actually
exists.
So increasing food production by 50% and energy reduction by 50% are really challenging within
that scenario.
We also know that we are looking a world where the climate is becoming more unstable and
harder to predict and that has ramifications for food security in particular.
So if we look at energy so currently as I said we are looking at about 50% in increase
in energy and look at how we consume energy about 1/3 of it goes into heat production
in northern climes like ours about 1/3 into grid electricity consumption and about 1/3
into things liquid transportation fuels for the transportation system.
So we know that if we are worried as we are about greenhouse gas emissions, about climate
change resulting from that we know that is aspirating our current situation we as a nation
are committed to reducing our carbon emissions by about 80% by 2050.
We have to think how we are going to do that whilst maintaining at least the amount of
energy that we produce and consume or is that the way we do it or do we have to demand production.
If we look at the energy matrix we can realise that we can generate heating and electricity
from a whole range of different renewables that have low carbon foot prints and things
like solar energy, wind energy etc.
The areas which are really tricky to deal with are the liquid transportations fuels
and also things like these are things which we get from petroleum really other things
that are hard to deal with so mostly we use petroleum to make liquid transportation fuel
and also to make chemicals, materials.
So the chairs you are sat on are made of oil, the cars or the vehicles you arrived in mostly
would have been burning liquid transportation fuel and what we will be talking about tonight
what we are considering is about how bioenergy fits into these scenarios.
So we can think about bioenergy as falling into two areas, I would say.
One of them is we can use plant biomass to produce electricity and we are already doing
that in our power stations we are co-firing biomass from all over the world at this point
in time.
And we can also consider the production of biofuels which replaces the liquid transportation
fuels and those biofuels we generally sort of lump into a couple of different areas.
One of them is the first generation biofuels those are the ones we produce at the moment
these are things like biodiesel, which we make from plant oil, so the sort of oil is
an oil seed rape from sunflowers, soil beans etc and also there is bioethanol which is
produced by fermentation from starch or from sugars and the thing you can note about all
of those it that they are all fruit commodities and there is fuel problem there as I mentioned
we need to increase food production very markedly in the coming years and if we expand biofuel
production at the same time obviously there is a real clash of interest affair.
So a lot of the focus is going into what we call second and third generation plants biomass
and second generation is all about looking at the bits of plants that we currently don't
use for fuel and those are typically the woody parts, so the stems of crops like cereals
and if you look at cereals there is more energy tied up in the stems of those crops than there
is actually in the grains that we use for food and a lot of that energy is tied up in
polymers that are polysaccharides, things that can convert into sugars and used in fermentation
and get away from the need for the use of starch in sugars.
So if we can move towards using both those sorts of parts of crops, food crops there
is potentially a use to make biofuels that way.
There is also a lot of interest in dedicated biomass crops these are things that have very
high yields typically high yielding than food crops and ideally they are crops that can
be grown on more marginal ones than not using food production and there is a lot of interest
here and around the world and looking at using some more of our marginal land for that particular
kind of use.
I note the third generation of biomass crops are the ones which are being engineered for
higher yield for better applications in biofuels terms and what we are trying there to do is
to increase the actual yield of energy per hector that we could get out of both dedicated
biomass crops and also these nonfood parts of the crops we talk about.
Another area we encounter is there is a lot of interest at the moment in the use of microalgae
as a source of biofuels and there is a lot of interest in them because the yield per
unit area in theory can be higher than we currently get from crops.
So there is some interesting ways that we can decarbonise the current energy in biofuel
scenarios we have in this country because by using biological materials like I probably
missed that point at the start we are using the carbon that is fixed by photosynthesis
and is then released so in theory you can have carbon neutral energy that is compared
to the every increasing loads of CO2 from burning fossils so I think that is all I am
going to say in terms of trying to give a very brief flavor of how biofuels and bioenergy
fit into those scenarios.