reaten the Earth - yet energy demands will rise by 50% to 60% by 2030. We
need to rapidly develop sustainable solutions - from hydrogen cells to wind turbines - to fuel
Most of the energy on Earth
comes from the Sun. In fact enough
energy from the Sun hits the planet's surface each minute to cover our needs
for an entire year, we just need to find an efficient way to
harness it. So far the energy in oil has been cheaper and easier to get at.
But as supplies dwindle, this will change, and
we will need to cure our addiction to oil.
Thirst for oil
satisfied most energy needs until the steam-driven industrial
revolution, when energy-dense coal became the fuel of choice. Coal is
still used, mostly in power stations, to cover one-quarter of our energy needs,
but its use has been declining since we started pumping up oil. Coal is the
least efficient, unhealthiest and most
environmentally damaging fossil fuel, but could make a comeback, as
supplies are still plentiful: its reserves are five times larger than oil's.
(derived from oil) provides around 40% of the world's energy needs, mostly
fuelling automobiles. The US guzzles up a quarter of
all oil, and generates a similar proportion of greenhouse gas
emissions. The first wells were drilled 2400 years ago,
but the modern oil industry was born in the 1850s.
The majority of oil comes
from the Middle East, which has
half of known reserves. But other significant sources include Russia, North America, Norway, Venezuela and
the North Sea. Alaska's Arctic National Wildlife Refuge
could be a major new US source, to reduce reliance on
foreign imports, but drilling there is currently prohibited.
Most experts predict we
will exhaust easily accessible reserves within 50 years, though opinions and estimates vary. We
could fast reach an energy crisis in the next few decades; when demand outstrips supply.
As conventional reserves become more difficult to access, others such as oil shales and tar sands may be used instead. Petrol
could also be extracted from coal.
Since we started using
fossil fuels, we have released 400 billion tonnes of carbon, and burning the
entire reserves could eventually raise world temperatures by 13°C. Among other horrors,
this would result in the destruction of all rainforests and the
melting of all Arctic ice. London
would be as hot as Cairo, but would also be engulfed by seawater.
(See our Special Report on Climate Change for
Natural gas reserves could plug some of the gap
from oil, but reserves of that - some of which are in Russia, the Middle East
and the Wadden Sea - will not
last into the 22nd century either. We currently use it
for around one-third of world electricity generation.
Natural gas, which is
mostly methane, is the cleanest fossil fuel by
weight, emitting just 40% the greenhouse gases of coal and 25% of oil. As a
less-polluting alternative to petrol, its use is increasing in automobiles -
either as compressed natural gas
or for powering hydrogen fuel cells.
When reserves do run low, we may be able to access vast frozen methane hydrate
reserves beneath the seabed.
In the next few decades,
one way for the UK and others to
meet greenhouse gas reduction commitments, could be increased nuclear power
generation. Currently, about 440 reactors in 32 countries generate 16% of world
electricity. (See our Special Report on The Nuclear Age for
Despite a slow decline of
support for nuclear power in the
west following the Chernobyl disaster in
1986, many countries, such as the US, Japan and India are now embracing
the technology again. But using nuclear power to mitigate environmental damage
is a double-edged sword,
because disposing of nuclear waste is itself
an intractable problem. Expense, safety in usual
operation and terrorism are major concerns too, not
to mention the fact that building new facilities can take decades.
energy sources offer a more practical long-term energy solution. They may benefit the world's poor
too. "Renewable" refers to the fact these resources are not used
faster than they can be replaced.
The Chinese and Romans used
watermills over 20