Climate Action 2011-2012

Steps to Sustainability
hydropower
© iStockphoto
Hydropower has a global installed capacity of around 950GW.
Hydropower and
climate change
142 climateactionprogramme.org
By Cameron Ironside, Programme Director,
International Hydropower Association (IHA)
Hydropower already satisfies a significant portion of the
world’s energy requirements. Its influence will increase
in a climate changed world as it not only facilitates
adaptation through water storage, but also enables the
large-scale integration of renewables into energy systems.
Hydropower plays a unique role in advancing global
renewable energy systems and has the ability to respond
to global energy needs.
Hydropower is a renewable energy source generating
electricity through the movement of water from a higher to
lower elevation. Its energy conversion rate of 90 per cent is
the highest of any known energy source. Hydropower has
a global installed capacity of around 950GW – 19 per cent
of worldwide installed electricity capacity – and generates
approximately 16 per cent of the electricity used worldwide.
This installed capacity represents a small portion of
international hydropower potential, especially in the areas
where it will be most required in a climate changed world.
For example, Africa currently only utilises approximately
five per cent of its hydropower potential.
Impact of a changIng clImate
on hydropower
It is clear that changes in climate will impact on hydropower:
as different areas go through climatic changes, these changes
will impact on the rivers that feed hydrological systems. The
changes in river runoff will thus dictate the changes to the
availability of hydropower as a resource.
While there are currently no global figures predicting the
effects of climate change on the technology, a recent study
by Hamadudu and Killingtviet (2010) which analysed
the changes to river flows, as predicted by 12 different
climate models, to consider the effects globally on existing
hydropower, provides some indication: while the results
indicate significant changes on a country or regional level,
they suggest that the total global change to the hydropower
system is small (around 2.5 per cent).
Hydropower has a role
to play in both mitigating
against and adapting to the
effects of climate change.
These results match the anecdotal evidence from within
the membership of the IHA. While some countries, such as
Australia, are already experiencing negative impacts, others
such as Norway are anticipating increases in potential.
Again, while more detailed studies are required, it is clear
that changes will vary by region and will be both positive
and negative. Currently, it is thought that the overall impact
will be small, and possibly slightly positive.