GRAVITY BATTERY - SCI & TECH
News: Australian technology may help generate power from defunct gold mines
in Kolar Gold Fields
What's in the news?
● An
Australian renewable energy company’s unique scheme to generate electricity
may resuscitate the fortunes of one of India’s iconic but defunct gold mines,
namely the Kolar Gold Fields (KGF), in
Karnataka.
Need of Gravity Batteries:
A
hiccup that makes renewable energy unreliable, from solar or wind power, is
that there is no power during nights or windless days. Green Gravity's idea is
to address this challenge by relying on low tech gravity.
● Their
plan is to find defunct mines, which
often go hundreds or even thousands of meters deep, and haul a ‘weighted block’
— this could be as much as 40 tonnes — up to the top of the mine shaft using
renewable power during the day when such power is available.
● When
backup power is required, the heavy
block will fall, under gravity, and the ensuing momentum will power a generator
via a connected shaft. The depth to which the block can slip can be determined
via a braking system, thus giving control on the amount of power that can be
produced.
● The
same principle underlies the ‘pumped
hydropower’ storage.
● Eco friendly:
Using weighted blocks means that decommissioned mines can be put to use and the
environmental costs and challenges of moving water up can be avoided,
○ By
using gravity as the fuel, we dispense with consuming the critical water, land,
and chemicals which other storage technologies rely on.
● Potential:
At mines such as at Kolar, India can produce up to 100 or even thousands of
megawatt hours of power.
Gravity battery:
● A
gravity battery is a type of electricity
storage device that stores gravitational energy, the energy stored in an
object resulting from a change in height due to gravity, also called potential energy.
● A
gravity battery works by using excess energy from the grid to raise a mass to
generate gravitational potential energy, which is then dropped to convert potential energy into electricity
through an electric generator.
● Energy
generated from a gravity battery is a form of sustainable energy.
● One
form of a gravity battery is one that lowers
a mass, such as a block of concrete, to generate electricity.