The document discusses blue energy as a renewable energy source generated through reverse electro-dialysis, utilizing the potential difference between fresh and saltwater at river deltas. While the technology shows promise with an efficiency of 85 to 90%, the high cost of membranes poses a significant barrier to its economic feasibility. The construction of a blue energy facility in the Netherlands exemplifies its potential, though ongoing research aims to optimize costs and enhance energy output.

1. BLUE ENERGY
THE RENEWABLE SOURCE
LDRP-ITR,GANDHINAGAR,
RUCHIR OZA(08EE030)
,
INSTITUTE OF TECHONOLOGY, NIRMA UNIVERSITY
AHAMDABAD,
MAYUR PAREKH (08BEE031)
I. INTRODUCTION
With the growing dynamism and
competition in the world, energy has
become one of the most valuable and
desired resources. Besides that, it is already
becoming an enormous concern for some
countries due to the lack of non-renewable
fuels and their astronomically high price. In
general, almost all countries in the world
suffer a negative impact from the price hike.
So, the world is looking forward to some
renewable energy that can be effectively
used against this growing demand of energy.
Blue Energy is one of those renewable
resources. The Blue energy is generated by
the process of Reverse Electro-Dialysis. The
method is inherently sustainable and clean.
So, there are no prominent environmental
harmful impacts.
II. BLUE ENERGY
At river deltas large amounts of fresh water
run into the salt sea water.
When these two types of water blend the
entropy of the total system increases,
reducing the ordering.
Energy can be derived from this
spontaneous process if it is carried out in a
controlled way. This method of power
generation does not consume fossil fuel and
neither produces CO2 and is therefore a
sustainable type of energy. It is called Blue
Energy.
Fig. 1 Scheme Of Blue Energy
For the generation of blue Energy ‘Reverse
Osmosis Process’ is carried out. Due to
which salt particles will get segregated from
the salt water solution.
III. REVERSE OSMOSIS
Reverse osmosis (RO) is a filtration method that
removes many types of large molecules and ions
from solutions by applying pressure to the
solution when it is on one side of a selective
membrane. The result is that the solute is
retained on the pressurized side of the membrane
and the pure solvent is allowed to pass to the
other side. To be "selective," this membrane
should not allow large molecules or ions through
the pores (holes), but should allow smaller
components of the solution (such as the solvent)
to pass freely. Blue Energy by reverse osmosis
requires membranes that block salt
particles but allow water diffusion. The salt
water and river water are separated by a
semi-permeable membrane and 11-15 bar
pressure is applied on the salt water to

2. facilitate the flow of water particles from
salt water to fresh water. And the salt
particles, unable to pass through the
membrane, will accumulate near the surface
of membrane.
Fig. 2 Reverse Osmosis
IV. GENERATION OF BLUE
ENERGY (RED-Reverse
Electro Dialysis)
For generation of blue energy the process of
reverse osmosis is useful.
The membranes, used in the reverse osmosis
process, are separately excited by an
external voltage source. So, when an reverse
osmosis process happens the salt particles,
unable to pass through membranes, will get
ionized and the positive Sodium(Na) ion
will be attracted towards cathode and
negative chlorine(Cl) ion towards anode.
When any of the ion will pass through the
membrane it will generate certain amount of
current in that particular membrane.
Connecting such membranes in series we
can fetch a high amount of energy, known as
Blue Energy. And the entire process is
called the process of ‘Reverse Electro-
Dialysis’ (RED).
The schematic diagram of this procedure is
shown in Fig.3.
Fig. 3 Blue Energy By Reverse Electro-Dialysis
V. RUNNING PLANT IN
THE NETHERLANDS
For generation of electricity in the form of
Blue Energy, a plant is established in The
Netherlands. Sea water and river water
required for this plant are obtained from the
Rhine River Delta. Around 3300 cubic
meter water quantity is required on an
average for this process. The size of the
plant is 90 meter square. The working
pressure is kept in between 11 and 15 bars.
The energy generated in this plant is 250kW
which can go up to 4.5 GW. Such a
discrepancy exists because this plant is not
working at its full capacity as this project is
still under research. The researchers are
trying to pull down the cost of membrane
through the invention of any new
technology. Solving this problem the plant
may run at its full capacity and produced
energy as high as 4.5 GW.

3. VI. RIVER DELTA
The Blue Energy Plant can be set up
wherever the river water and the salt water is
available in a large quantity.
One of the such places are River Deltas
exist in world. The River Delta is a place
where a river and an
ocean or a sea meets. Thus at this place the
river water and the salt water will be
available in a large quantity to establish a
plant. The Netherlands plant is established
near the river delta of the Rhine River. The
location of all the river deltas in the world is
shown in the Fig. 4. At these locations the
plant can be established to get the Blue
Energy.
VII. ADVANTAGES
There are certain advantages of this
technology. It is a renewable source of
energy. As the river water and salt water can
be obtained frequently for the execution of
this process. Its efficiency found to be 85 to
90% as there are not any prominent losses in
this process. Here the energy can be got 24
hours continuously unlike solar energy or
wind energy. This technology is almost
pollution free. And the river deltas are
largely available in the world so this kind of
plant can be set up worldwide.
VIII. DISADVANTAGES
There will be ‘Salinity’ fluctuation as the
river water and sea water are mixed. In this
process the cost of the membrane is the
highest. So, to increase the energy
production the number of membrane used
will increase and hence overall cost will go
high. The energy gained by this process is
D.C. and most of the electrical equipments
are working on A.C. supply. So, we will
have to convert this D.C. power to A.C.
power.
After the continuous use of membrane it
may require certain amount of maintenance
.And this maintenance cost will be high in
case of this membrane.

4. IX. CONCLUSION
The present paper discussed the application
of Blue Energy as a realistic form of
sustainable energy. Though the
Technology as such is proven to be feasible,
the price of current membranes make Blue
Energy not cost effective to date. The major
barrier for this technology is economy of
membranes.
REFERENCES
[1]Ross, R., and Krijgsman, J. “New Ionomer Membranes for
Blue Energy”, an IEEE Paper
[2]http://en.wikipedia.org/wiki/BlueEnergy
[3]http://en.wikipedia.org/wiki/Reverse_osmosis
[4]http://powerplants.einnews.com/netherlands/
[5]Dr. Mark Krinker, and Professor Aron Goykadosh “Renewable
and Sustainable Energy Replacement Sources”
[6]http://www.odemagazine.com/doc/61/blue-energy/
[7]http://www.bluenergy.com/Ecological.htm
[8]http://www.sciencedirect.com/
[9]http://en.wikipedia.org/wiki/River_delta/
[10]http://en.wikipedia.org/wiki/BlueEnergy/
[11]http://www.elsevier.com/