FRIDAY 19 SEPTEMBER, 2008 |

Breakthrough in Renewable Energy Storage
by Energy Matters
One of the holy grails of large scale
renewable
energy has been conquering the challenges posed in storing electricity
generated by
solar
power and
wind
energy systems.
In large scale systems such as solar and wind farms of the future, huge amounts
of storage capacity will be vital for times when the wind doesn't blow or the
sun doesn't shine so that the mains grid can receive a continual supply. The two
solutions currently with the best potential are
molten
salt storage systems and
ultracapacitors;
also known as super capacitors.
Engineers and scientists at The University of Texas at Austin
recently
announced a breakthrough that may lead to the ability of storing massive
quantities of electricity in ultracapacitor devices.
The researchers have been investigating the use of a one-atom thick structure
called "graphene" (a form of carbon) that could double the capacity of
existing ultracapacitors which currently use an entirely different form of
carbon.
According to Rod Ruoff, a mechanical engineering professor and a physical
chemist on the team, ""Graphene's surface area of 2630 m
2/gram
(almost the area of a football field in about 1/500
th of a pound of
material) means that a greater number of positive or negative ions in the
electrolyte can form a layer on the graphene sheets resulting in exceptional
levels of stored charge."
This technology has the potential to not only store electricity for renewable
energy systems, but significantly improve efficiency and performance of electric
and hybrid cars and other forms of transportation, along with smaller devices
such as office and communications equipment.
While
deep
cycle batteries are the most popular way to store electricity generated by
renewable energy, ultracapacitors are becoming increasingly commercialised; but
at this point mainly for high-end industrial uses or for small electronics - it
will still be some time before ultracapacitors are made available for
applications such as
home
off grid solar power systems.
Advantages of ultracapacitors over deep cycle batteries include: higher power
capability, longer life, a wider temperature operating range, lighter, more
flexible packaging and lower maintenance.
Return to main renewable energy news section
Other Energy Matters News Services