Harnessing renewable energy in crz territory. by-Dr Arceivala
HARNESSING RENEWABLE ENERGY IN CRZ TERRITORY
Prof Soli J. Arceivala
Formerly, Director, NEERI, Nagpur and Chief, Env Health, UN/WHO SE Asia Region
Coastal areas are now being put to newer uses which we did not even imagine a few years
ago. Coastal areas have now become important sources of electricity from wind and wave
energy. India has a long coastline, and many of our large cities and towns located on it like
Mumbai, Chennai and Kolkata are in constant need of more electrical energy. Harnessing
renewable energy from wind and waves will increasingly happen in future and some
structures will have to be constructed within CRZ territory for the purpose.
The objective of my intervention is to request that the location of these structures in CRZ
territory should not become unduly difficult because of any new Regulations that may come
up. Whatever new Regulations are made should not cause undue problems for us in
securing permissions to construct them.
The Norwegian energy giant “StatoilHydro” has successfully built the world’s first full-scale
floating wind farm on the open sea as an experiment to harvest electricity in an environment
of strong, low-level winds and fewer space restrictions than are found on land. The US has
approved construction of the first offshore wind farms in Massachusetts and Germany has
likewise approved installations in the North Sea.
Even though capital costs are considered to be much higher for sea-based systems than for
land-based systems, and permissions are needed from more authorities than earlier, the
idea is sure to catch on in India where land is difficult to get anywhere inland. Using the open
sea or part-sea-part-land may seem attractive where land purchase seems difficult or ridden
with politics. The method is destined to increase electricity production substantially in the
future and some conflicts with CRZ regulations may arise.
Construction for harnessing wind energy mainly consists of erecting several wind towers or
slender columns to carry the turbines and 3-bladed fans. Connecting cables and operating
platforms, etc, have to be provided. Generally, these are provided in the continental shelf
area with a foundation on the sea floor. In deep sea conditions and where soil does not
permit fixture of the wind turbine column to the soil with a solid foundation, the slender
columns are kept hollow and filled with gravel and water as ballast. Slack moorings anchor
these turbine columns to the seafloor.
Another important form of renewable energy is wave energy. Scope exists for its usage in
India. Not much research work, however, appears to have been done as yet in India with this
system, and I would like to urge organizations like NEERI to consider undertaking some
research work in this regard.
Wave energy would appear to be more promising for use in India. The wave potential is said
to be around 1,000 times more than the wind potential. Waves are a stable and predictable
source of power, taking into consideration diurnal and seasonal variations. Wave energy
results in a substantial quantum of power generation since the energy generated varies
according to the square of wave height. In addition, water is some 850 times denser than
air. Infrastructure requirements are also said to be much less, since wave energy needs only
1/200 of the land area of wind energy. Generating wave energy entails lower infrastructure
According to an UNFCCC update (EB 51) four different technologies are under development
in USA and elsewhere. Among the mature ones, is the “Terminator” installed near shore in
California and is capable of producing electricity at about 10 cents/KWh (Rs 5 to 6 per kWh).
In India, the cost would surely be lower. I am illustrating the principle below in Fig 1.
Portugal and Philippines are also reported to be working on these devices.
No R & D project on wave energy harnessing yet appears to have been set up in India in
spite of its long coastline. The presence of important ports and cities on India’s coasts would
indicate a great scope for use of such devices to convert wave energy into electricity at
reasonable cost. Every city is hungry for more electricity. In my opinion, India must pay
very serious attention to this source of renewable energy. Its cost seems affordable, its
technology not very difficult and 3 major cities (Mumbai, Chennai and Kolkata) are on the
Fig 1 shows a turbine device to generate electric power from wave energy.
Possible conflict with CRZ rules
The location of the structures would generally be within the CRZ territory. Both the above
methods entail some structures to be erected in CRZ territory. However, insignificant these
structures may be, the related processing work to obtain no-objection-certificates (NOC’s)
may become formidable tasks unless specific exemptions are included in the bye-laws.
The purpose of this presentation is to draw the attention of experts attending this workshop
to this aspect of the problem as it is feared that unnecessary paperwork may slow down the
implementation of useful renewable energy projects.
Waves make water rise and fall in chamber
This forces the air back and forth through turbine
and generates power