ARTICLES
Solar PV and Wind are on track to Replace all Coal, Oil and Gas
within Two Decades
By Andrew Blakers and Matthew Stocks
Solar photovoltaics are now the world’s leading source of new electricity generation. US Air Force.
Solar photovoltaic and wind power are rapidly getting cheaper
and more abundant – so much so that they are on track to entirely
supplant fossil fuels worldwide within two decades, with the time
frame depending mostly on politics. The protestation from some
politicians that we need to build new coal stations sounds rather
quaint.
• minimal security concerns in respect of warfare, terrorism and
accidents;
• low cost;
• already available in mass production.
Solar PV meet all of these criteria, while wind energy also meets
many of them, although wind is not as globally ubiquitous as
sunshine. We will have sunshine and wind for billions of years
to come. It is very hard to imagine humanity going to war over
sunlight.
The reality is that the rising tide of solar photovoltaics (PV)
and wind energy offers our only realistic chance of avoiding
dangerous climate change.
No other greenhouse solution comes close, and it is very hard
to envision any timely response to climate change that does not
involve PV and wind doing most of the heavy lifting.
Most of the world’s population lives at low latitudes (less than
35°), where sunlight is abundant and varies little between
seasons. Wind energy is also widely available, particularly at
higher latitudes.
About 80% of Australia’s greenhouse gas emissions are due to
the use of coal, oil and gas, which is typical for industrialised
countries. The land sector accounts for most of the rest.
PV and wind have minimal environmental impacts or water
requirements. The raw materials for PV – silicon, oxygen,
hydrogen, carbon, aluminium, glass, steel and small amounts of
other materials – are effectively in unlimited supply.
Sadly, attempts to capture and store the carbon dioxide
emissions from fossil fuels have come to naught due to technical
difficulties and high cost. Thus, to curtail global warming we need
to replace fossil fuel use entirely, with energy sources that meet
these criteria:
• very large and preferably ubiquitous resource base;
• low or zero greenhouse gas emissions and other environmental
impacts;
• abundant or unlimited raw materials;
Wind energy is an important complement to PV because it often
produces at different times and places, allowing a smoother
combined energy output. In terms of worldwide annual electricity
production wind is still ahead of PV but is growing more slowly.
The wind energy resource is much smaller than the solar resource,
and so PV will likely dominate in the end.
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SCIENCE EDUCATIONAL NEWS VOL 67 NO 2