many barrels of oil does it take to power the economy? Far from the
punchline of a joke, the answer outlined by Dr Mike Joy, a
senior researcher at Victoria University of Wellington’s Institute
for Governance and Policy Studies,
in a public lecture highlights some disturbing truths about our
reliance on oil, the importance of energy to the economy, and how we
might “transition to a de-carbonised world”.
with the dire
more than 20,000 scientists worldwide that “if the world doesn’t
act soon, there will be catastrophic biodiversity loss and untold
amounts of human misery”, Joy went on to introduce the field of
Biophysical Economics and one of its key concepts—Energy return on
energy invested (EROI), or “how much energy do you have to put in
to get that back?”.
Economics uses material and energy flows, rather than prices, to
evaluate the economy, and it’s clear economists have underestimated
the significance of energy in production. People also seem to
underestimate how hard it is to replace energy production and how
much it takes to produce energy,” said Joy.
don’t realise most of the food that is produced for people on this
planet comes from using fossil fuels. But the net energy from our oil
and gas supply is declining, which is going to have implications for
is a “double whammy” of the current need to use fossil fuels
continuing to expand globally, and the fact that the easily
accessible fuel is gone and what is left requires much more effort
and therefore energy and capital to extract and refine.
need to find four Saudi Arabias in the next 20 years to keep up with
speaker at the lecture and a transition engineering
this assessment in perspective by pointing out that “we’re now
producing and consuming two to four barrels of oil for each barrel we
another way, we need to find four Saudi Arabias in the next 20 years
to keep up with consumption. The reality is that oil is the weak link
in the production and delivery of virtually all other forms of
energy, commodities, food, goods and services. Oil is, in many
respects, the master resource,” Surendran said.
spite of acknowledging the importance of oil to economies, both Joy
and Surendran are in agreement about the need for New Zealand and the
world to be carbon neutral by 2050 to keep global temperature rise
what about the promise of renewable energy in achieving this goal?
many people may think a transition to renewable energy will be a
“lovely carry-on-as-we-are world with no more petrol pumps”, Joy
is sceptical about the “bright green future we’re being told
to what most people believe, we are using proportionally less
renewable energy than we did previously. That is a huge issue. But
there’s also the fact that the EROI on renewables like photovoltaic
(solar panels), wind and biofuels poor and can’t sustain our
current energy needs,” said Joy.
best way to compare all the possible energy sources and realise
limitations on that green future, is by looking at these renewable
energy sources in terms of watts per square metre—how much area of
land does it take for each renewable energy source to meet current
the formula of energy used per person and population density, Joy
used the example of Britain to highlight the issue of relying solely
on current renewable energy sources, as every square metre of the
country would need to be covered in wind farms and solar panels to
meet energy needs.
energy density of our alternatives is so much lower than fossil
fuels, but if we want to keep under the 1.5oC threshold, we have to
reduce our emissions by 6 percent per year from today,” said
we’re going to have to get used to having a whole lot less energy
than what we had before, and that’s our only future. We have to
figure out how we’re going to do that.”