Improvements in Means for Obtaining Motive Power from the Rise and Fall of the Tides.
Year: 1897

page_text: PROVISIONAL SPECIFICATION.
Improvements in Means for Obtaining Motive Power from the Rise
and Fall of the Tides.
I, ALPHONSO STEIGER, of 16, Mincing Lane, London, E.C., Civil Engineer, do
hereby declare the nature of this invention to be as follows:-
-
According to this invention I build across the bed of a tidal river at or near its
mouth, or across the mouth of a tidal basin, a dam and use the space thus separated
from the sea as a reservoir into which the water is discharged from one or more
turbines during the rising tide, or from which water is supplied to the turbines
during the falling tide.
Docks which are deep enough to keep vessels afloat at low tides may also be
used as reservoirs.
The dam separating the reservoir from the tidal way is composed of a chamber
or a series of chambers into which the turbines are placed.
Underneath each chamber, and parallel with the How of the tides, there is a
tunnel, or an iron tube through which the water is taken to the turbine or turbines.
The tunnel or tube is provided with a throttle valve or similar contrivance at each
end to admit water to the turbine either from the tidal way or from the reservoir.
The turbine chamber is similarly provided with a gate at each end to discharge
the water either into the reservoir or into the tidal way. A turbine-chamber may
contain one or more turbines and there may be one common tunnel for several'
turbines placed in one chamber, or each turbine may have a separate tunnel, but
each tunnel communicates with the corresponding chamber through a turbine or
turbines mounted in the roof of the tunnel.
The turbine is placed in or near the level of the tailwater at low tides.
The manner of working is as follows:
Starting at the low tide, the upper gate only (that is to say the gate at the end
of the turbine chamber towards the reservoir) is open. When the tide has risen
so much that a fall of say three feet is available, the lower throttle-valve (that is
to say the valve or sluice at the lower end of the tunnel) is opened. The water is
thus admitted through the tunnel to the turbine or turbines and, after it has given
off its available energy, discharged upwards into the reservoir. As the tide is
rising, the tailwater level will also rise, according to the volume of water discharged
into the reservoir or the capacity of the latter. The turbine is preferably provided
with a suitable regulating device to keep power and speed constant within certain
limits of a varying fall.
When the tide has reached the highest level, the turbine may continue running
under a reduced fall, but it is preferable to utilize the fall still available to bring
the level of the water in the reservoir to the highest tide level by opening the lower
gates and thus letting the water flow into the reservoir direct from the tidal way.
The turbine is stopped by closing the lower throttle valve or sluice.
When the tide begins to fall, the upper gates are closed and, as soon as a suitable

page_text: fall, say three feet or less, is available, the turbine is again started by opening the
upper throttle valve. The turbine will continue to work until the tide has reached
its lowest level or until the fall is reduced to a useful minimum which may be 15
or 18 inches.
Then the upper throttle valves are closed and the upper gates opened to arrive
at an even level of the water in the reservoir and in the tidal way. The lower gates
are then closed and the operations will begin again when the tide has risen
sufficiently as already described.
If any water is supplied into the reservoir beyond that from the rising tide, or
if the reservoir is smaller in proportion to the power developed, then the time for
stopping the turbines may not coincide with the time when the tide has reached
its highest or lowest level, but only in the case of too small a reservoir would this
reduce the amount of power developed within 24 hours, while in the case of water
being delivered into the reservoir, the time of working lost during the rising tide
is recovered during the falling tide when the extra supply of water from the river
will maintain or sometimes increase the available fall as well as the power.
A constant or nearly constant power may be thus obtained from the rise and fall
of the tides for 18 to 22 hours out of every 24 hours.
Although I prefer to use axial flow turbines with vertical axes and arrange
them in such a manner that the water will flow from the tunnel through the
turbines into the reservoir, that is to say upward, the arrangement may be reversed
so that the water flows from the reservoir i.e. turbine chamber through the turbines
into the tunnel, that is to say downward.
The power obtained by the turbines is preferably applied in the first instance
to charge hydraulic or electrical accumulators, or to compress air, because by these
means the power is made available at any time, even when the turbines are stopped,
and can easily be transmitted to long distances, or distributed for various purposes.
If the dam containing the turbine chambers is placed across a navigable river,
locks are provided for the passage of vessels, barges, etc., so that the navigation
does not interfere with, or is not interfered with by the working of the turbines.
Dated this Twenty-second day of November 1897.
Improvements in Means for Obtaining Motive Power from the Rise
and Fall of the Tides.
I, ALPHONSO STEIGER, of 16, Mincing Lane, London, E.C., Civil Engineer, do
hereby declare the nature of this invention and in what manner the same is to be
performed, to be particularly described and ascertained in and by the following
statement:-
According to this invention I build across the bed of a tidal river at or near its
mouth, or across the mouth of a tidal basin, a dam and use the space thus separated
from the sea as a reservoir into which the water is discharged from one or more
turbines during the rising tide, or from which water is supplied to the turbines
during the falling tide.
Docks which are deep enough to keep vessels afloat at low tides may also be
used as reservoirs.
The dam separating the reservoir from the tidal way is composed of a chamber
or a series of chambers into which the turbines are placed.
Underneath each chamber and parallel with the flow of the tides, there is a

page_text: tunnel, or an iron tube through which the water is taken to the turbine or turbines.
The tunnel or tube is provided with a throttle valve or similar contrivance at each
end to admit water to the turbine either from the tidal way or from the reservoir.
The turbine chamber is similarly provided with a gate at each end to discharge
the water either into the reservoir or into the tidal way. A turbine chamber may
contain one or more turbines and there may be one common tunnel for several
turbines placed in one chamber, or each turbine may have a separate tunnel, but
each tunnel communicates with the corresponding chamber through a turbine or
turbines mounted in the roof of the tunnel.
Figure 1 represents a longitudinal section through the turbine chamber.
Figure 2 shows a cross-section through same and Figure 3 a plan, partly in
section.
A A in Figures 1 and 2 indicate the tunnel, eventually also an iron tube through
which the water is admitted to the turbine.
BB represents the turbine chamber which is used as tailrace and C is the turbine.
D is the throttle valve connecting or disconnecting the turbine with the tidal way
and D the throttle valve connecting same with the reservoir. E and E
represent the corresponding gates in the turbine chamber and FI Ft
the grating at both ends of the tunnel. G and H are manholes
closed by cast-iron lids to give access to the turbine chamber and the tunnel, J is
the turbine shaft by which the power is transmitted and which is suspended on the
footstep K placed above the turbine chamber. L represents the lowest waterlevel
at ebb-tide and at the same time the lowest tailwaterlevel, while L' indicates
the lowest headwaterlevel, say about 3 feet above L with which fall the turbine
may be conveniently started. L2 and L* indicate respectively the highest tail- and
head-waterlevels. The position of the throttlevalves, gates and waterlevels
correspond with the working of the turbine during a rising tide, the arrows indicat-
ing the direction in which the water flows.
The turbine is placed in or near the level of the tailwater at low tides.
The manner of working is as follows:
Starting at the low tide the upper gate E¹ only (that is to say the gate at the end
of the turbine chamber towards the reservoir) is open. When the tide has risen
so much that a fall of say three feet is available the lower throttle-valve D (that
is to say the valve or sluice at the lower end of the tunnel) is opened. The water
is thus admitted through the tunnel to the turbine or turbines and, after it has
given off its available energy, discharged upwards into the reservoir. As the tide
is rising, the tail-water level will also rise, according to the volume of water dis-
charged into the reservoir or the capacity of the latter. The turbine is preferably
provided with a suitable regulating device to keep power and speed constant within
certain limits of a varying fall.
When the tide has reached the highest level, the turbine may continue running
under a reduced fall, but it is preferable to utilise the fall still available to bring
the level of the water in the reservoir to the highest tide level by opening the
lower gates E and thus letting the water flow into the reservoir direct from the
tidal way. The turbine is stopped by closing the lower throttlevalve or sluice D).
When the tide begins to fall the upper gates E are closed and as soon as a suit-
able fall, say three feet or less, is available, the turbine is again started by open-
ing the upper throttle-valve D. The turbine will continue to work until the tide
has reached its lowest level, or until the fall is reduced to a useful minimum which
may be 15 or 18 inches. Then the upper throttle-valves D¹ are closed and the
upper gates E opened to arrive at an even level of the water in the reservoir and
in the tidal way. The lower gates E are then closed, and the operations will begin
again when the tide has risen sufficiently, as already described.
If any water is supplied into the reservoir beyond that from the rising tide, or
if the reservoir is smaller in proportion to the power developed, then the time for
stopping the turbines may not coincide with the time when the tide has reached
its highest or its lowest level, but only in the case of too small a reservoir would

page_text: this reduce the amount of power developed within 24 hours, while in the case of
water being delivered into the reservoir, the time of working, lost during the rising
tide when the extra supply of water from the river will maintain, or sometimes
increase, the available fall as well as the power.
A constant or nearly constant power may be thus obtained from the rise and fall
of the tides for 18 to 22 hours out of every 24 hours.
Although I prefer to use axial flow turbines with vertical axes and arrange them
in such a manner that the water will flow from the tunnel through the turbines into
the reservoir, that is to say upward, the arrangement may be reversed so that the
water flows from the reservoir, i.e., turbine chamber through the turbines into the
tunnel, that is to say downward.
The power obtained by the turbines is preferably applied in the first instance
to charge hydraulic or electrical accumulators, or to compress air, because by these
means the power is made available at any time, even when the turbines are stopped,
and can easily be transmitted to long distances, or distributed for various purposes.
If the dam containing the turbine chambers is placed across a navigable river,
locks are provided for the passage of vessels, barges etc. so that the navigation does
not interfere with, or is not interfered with, by the working of the turbines.
I am aware that it has been proposed to utilise the rise and fall of the tide by
means of turbines mounted on a vertically movable float or pontoon and also by
the combination of a turbine or turbines with two or more reservoirs the water
being at times supplied from one reservoir and discharged into another reservoir.
I do not claim any of these arrangements.
Having now particularly described and ascertained the nature of my sail
invention and in what manner the same is to be performed I declare that what
I claim is
1). The combination of a dam built across the. bed of a tidal river or across the
mouth of a tidal basin and containing a turbine-chamber, with a turbine mounted
in the said chamber, and a tunnel or tube extending across the dam and adapted
to admit water to the turbine chamber through the turbine, and a system of valves
or gates adapted to control the flow of water through the turbine, substantially as
described and for the purpose specified.
2). A turbine installation for utilising the rise and fall of the tide, chiefly com-
prising a dam built across a tidal river, or across the mouth of a tidal basin, one or
more turbine-chambers, one or more tunnels or tubes, and regulating or controlling
apparatus, the whole being constructed and adapted to operate substantially as
described and illustrated by the drawings.
Dated this Third day of Sentombar 1808
.ALPHONSO STEIGER.