Improvements in Means for Obtaining Motive Power from the Rise and Fall of the Tides.
Year: 1894

page_text: Date of Application, 29th Aug., 1894
Complete Specification Left, 28th May, 1895-Accepted, 17th Aug., 1895
PROVISIONAL SPECIFICATION.
Improvements in Means for Obtaining Motive Power from the Rise
and Fall of the Tides.
I, EDWARD DAVIES, of Cambridge Cottage, Wood Green London, N.
Engineer, do hereby declare the nature of this invention to be as follows :—
According to this invention I employ two reservoirs of dimensions suitable to
the power required, and which I call No. 1 and No. 2 reservoirs. By the aid of
the two reservoirs, and working from the tide direct, I can keep turbines or other
suitable water motors going continuously during the 24 hours, and if necessary
throughout the year. The bottom of No. 1, reservoir will be about on a level
with low tide, but may be higher; and the bottom of No. 2, reservoir may be
about level with the tide when about half high, more or less. A turbine race is
arranged in front of the reservoirs next to the tidal way: In this race are fixed
as a rule two turbines; but there may be more or only one to suit circumstances.
The turbines will be fixed 3 feet, more or less above the bottom of the turbine
race, which will be on a level with the bottom of No. 1 reservoir, or may be
higher. There is a water supply pipe on each side of the turbines, to work them.
One pipe receives the water direct from the tidal way through a sluice valve.
When the turbines are a considerable distance away from low tide the water can be
brought up the trough or pipes that take away the used water from the turbines to
low tide, and so to the feed pipe above mentioned. The other feed pipe on
the other side of the turbines receives its water through a sluice valve from
No. 2 reservoir. The turbines discharge their water on to the bottom of the
turbine race, from whence it runs through a sluice gate into No. 1 reservoir for a
given time, and for the rest of the time through a sluice gate into the tidal way
through troughs or pipes or other means.
The above arrangement in practice works as follows:-Dealing with a tidal rise
and fall of 21 feet; assuming the turbines to be 3 feet above the bottom of their
race, this will give at high tide an eighteen feet head of water. At high tide
No. 2 reservoir is full of water and No. 1 reservoir is empty. The tide will rise
and fall 3 feet 6 inches per hour. To commence work the tidal water is admitted
to the turbines which are kept going for 12 hours, the water being delivered from
them into No. 1 reservoir, which must be of a suitable size for the purpose, the
tide will have lowered in the 13 hours 6 feet 1 inches. leaving 11 feet 10 inches
clear head of water; I now stop the water from the tidal way and work the
turbines from the water in No. 2 reservoir for 3 hours, still delivering the water
from the turbines into No. 1 reservoir. The tide has lowered in the 4 hours
16 feet 7 inches : keep on working from No. 2 reservoir for 1 hours longer, the
turbines delivering the water into the tidal way. The turbine has now been
working 6 hours and it is low tide (and No. 1 reservoir is emptied into the tidal
way). I still keep on working the turbine from No. 2 reservoir for 1 hours, the
water being delivered into the tidal way: The tide has risen in the 1 hours,
4 feet 4 inches. I still keep on working from No. 2 reservoir, delivering the
water from the turbine into No. 1 reservoir for 3 hours making 4 hours from low
tide. The tide has risen in the 4 hours, 14 feet 10 inches. I now shut the
water off from No. 2 reservoir and commence to work the turbines from the tidal
way for 1 hours, delivering the water into No. 1 reservoir; this makes 6 hours, and

page_text: it is again high tide (as when I started at first) and No. 2. reservoir is again filled ;
so that I go on with the same cycle of working continuously every hour, day and
night (if required) throughout the year. The turbines can be started to work at
any time day or night, and at any height of the tide, and even at low tide.
Dated this 28th day of August 1894.
Improvements in Means for Obtaining Motive Power from the Rise
and Fall of the Tides.
I, EDWARD DAVIES, of Cambridge Cottage Wood Green, Loudon, N.,
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 :-
This invention will be best understood by describing the same with aid of the
accompanying drawings.
Figure 1 plan of the entire means according to this invention.
Figure 2 sectional view on line X, Y.
Figure 3 sectional view on line X', Y', looking towards the tidal way.
Figure 4 partial view of Fig. 1 with modification.
According to this invention I employ one or two reservoirs of dimensions
suitable to the power required, numbered for convenience of reference 1 and 2; the
bottoms of these are placed at different levels to enable the rise and fall of the tides
to be utilised during every twelve hours to drive turbines as hereafter described.
I will proceed to describe the invention with reference to two reservoirs.
The bottom A, of No. 1 reservoir may be on a level with the top of the water B,
of the tidal way at low water; and the bottom C, of No. 2 reservoir about the top
of the water at half tide high. I propose to explain the invention dealing with
a tidal rise and fall of twenty-one feet.
The
The wall D, of the reservoirs facing the tidal way is provided with a turbine
race E, which shuts out the tidal water. In this race are arranged the
turbines F, F1, F2. The drawings show three turbines, but more or less may be
employed. These turbines are held to be about three feet above the level of the
bottom A, of No. 1 reservoir. At this level there is a sluice valve G, opening into
the tide water. This valve communicates with a feed tube H, for the turbines
when the latter are being worked by an inlet of water from the tidal way. The
turbines empty into the bottom of the race E, from which there is a communication
into No. 1 reservoir. This communication is closed by a sluice valve J. The
capacity of this reservoir should be such that the water running in from the race E,
should never rise above the level of the turbines. On the other side of the
turbines is another feed pipe K, to receive the water from No. 2 reservoir.
communication from the latter reservoir to the feed pipe is controlled by a sluice
valve L. The working is as follows:-As the turbines are placed three feet above
low water level, a tidal rise of 21 feet will give the turbines at high tide a head
of water of 18 feet. At high tide No. 2 reservoir is full of water which has come
in through the sluice M, then the latter is closed. At this time No. 1 reservoir is
empty. The tide will rise 3 feet 6 inches per hour. Working begins at high tide
by letting the water in from the tidal way for one hour and three-quarters, which
after passing through the turbines empties into bottom of race E, and runs into
reservoir No. 1, through the sluice way J. During this hour and three quarters
working the tide will have lowered 6 feet 11 inches, leaving 11 feet 10 inches of
water head. The tide water will now be shut off by closing valve G; and the

page_text: sluice L, of No. 2 reservoir opened and the water taken from this reservoir for
three hours, which runs into feed pipe K, and from thence through the turbines as
described into No. 1 reservoir. The tide will have lowered in 4 hours 16 feet
7 inches. For the next 12 hours the water is continued to be drawn from
No. 2 reservoir, but empties out into the tidal way. It will now be low tide when
the sluice N, of reservoir No. 1 is opened and the reservoir emptied of its water
into the tidal way, and any water in the turbine race can be also run out through
the sluice O. The turbines continue working with water from No. 2 reservoir for
a further 1 hours, the water running into the tidal way, when the tide will have
risen 4 feet 4 inches. Working is still continued from No. 2 reservoir for another
three hours, the water running into No. 1 reservoir, making 4 hours since_low
tide. During this 4 hours the tide will have risen 14 feet 10 inches. No. 2
reservoir is now shut off, and the turbines worked by water from the tidal way
for 1 hours, the water being delivered into reservoir No. 1. It is now high tide
again and No. 2 reservoir is once more filled for working.
By the above described means turbines can be worked day and night continuously
by tidal water throughout the whole year. The capacity of the reservoirs being
such as will receive and supply the requisite quantity of water necessary to work
the turbines. To obtain nearly even power in working, I find it advisable to vary
the size of the turbines, taking the smallest one with the highest head, and the
largest with the lowest head. When the reservoirs are placed a distance inland,
I use pipes M' and N¹, from the reservoirs to the tidal way. The feed pipe H, can
be connected to the side of the pipe N¹, as shown at Fig. 4, and the outlet from
turbine race by branch pipe O¹. When working with one reservoir only, (No. 1),
the working begins at half tide, the reservoir being then empty, and goes on for
six hours from the tidal way, the water running into the reservoir: When the
tide has fallen half way the working ceases, and at low tide the reservoir is emptied,
and working recommences when the tide has risen half tide high.
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed, I declare that what I
clain is :-
1. The combination of reservoir No. 1 and turbine race having their bottoms on
or about the same level, of turbines arranged a certain distance above the level so
that they may be free from working in tail water.
2. Feeding the turbines with water from two supply pipes, one connected with
the tidal way and the other with No. 2 reservoir.
3. The combined use of two or more turbines of different water capacities to
equalize the variations in power given by different heads of water during the rise
and fall of the tide.
4. The combination of two reservoirs and other means hereinbefore described
and illustrated by the accompanying drawings, for obtaining continuous motive
power from water by the rise and fall of the tides.
5. The combination with No. 1 reservoir and turbines, of the times of working
turbines with water taken from the tidal way for six hours continuously as
hereinhefore described.
6. The combination with two reservoirs and turbines, of the times for working
the turbines with water from No. 2 reservoir and from the tidal water, herein before
described.
Dated this 28th day of May 1895.
FREDERIC PRINCE,
37 Cursitor Street, London, E.C., Agent for Applicant.