Introduction
2022-12-13 I saw yet another documentary of how the Dead Sea on Israel/
Jordan border is still falling at one metre per year; & again
wondered if anyone yet had costed out how much hydro electric
power could be generated by a canal or syphon pipe from the
Mediterranean ?
Best cut the Palestinians & Jordanians in too on the
investment, building & maintenance work & profits.
"main, northern basin is 50 kilometres (31mi) long
and 15 kilometres (9mi) wide at its widest poin" (50 x 15 =
750, less allowing for non rectangular, narrower at
ends)
"its surface area today is 605 km2 (234 sq mi), having
been 1,050 km2 (410 sq mi) in 1930"
Question: is the 605 km2 just the main northern basin, or
including the southern basin ? The Southern Basin seems
to be about 50% of the Northern. Could that then be about
900 km2 ?
Searching finds:
www . saltworkconsultants . com / dead - sea - middle -
east /
"The Dead Sea water surface defines what is the
deepest continental position (-420 m asl) on the
earth's current terrestrial surface. It is our only
modern example where bedded evaporitic sediments are
accumulating on the floor of a deep brine body, where
water depths are measured in hundreds of meters.
Overall, this salt-encrusted depression is 80 km long
and 20 km wide, has an area of 810 km2, is covered by a
brine volume of 147 km3 and occupies the lowest part of
a drainage basin with a catchment area of 40,650
km3.
However, falling water levels in the past few decades
mean the permanent water mass now only occupies the
northern part of the lake, while saline anthropogenic
pans occupy the southern basin so that the current
perennial "Sea" is now only some 50 km long."
volume per year evaporating: = 605,000,000 cubic
metre
A canal/pipe will need some gradient to flow - Guess a 30 metres drop ?
(Later calculate the gradient &
drop).
One can't build turbines right down on the edge of the dead
Sea, where shallow land is unstable with sink holes (+ the
Dead Sea may rise not sink with this project!), so allow
some loss of height for shallow run off after last turbine,
& allow some extra height loss for intermediate pools,
so allow 50 meters ? So drop for turbines is 350
metres.
volume per year x density x drop height = energy per
year.
Sea water is a bit heaver/ denser than pure water, but
approx the same.
1 cubic metre 1,000 decilitre, each decilitre is 1 kg.
Assume gravity is 10 Newtons per Kg (its actually 9.8)
1 year = 365 x 24 x 60 x 60 = 8,760 hours = 31,536,000
seconds
1 newton metre = 1 joule
1 joule / sec = 1 watt
605,000,000 x 1,000 x 10 x 350 Nm / 31,536,000 secs =
605,000,000 x 10 x 350 Nm / 31,536 secs =
67,145,484 Watts
( 67 Mw is quite small, eg Hungary is
planning 2 x 1,200 MW nuclear reactors. ) 67 Megawatt x
8,760 hours = 588,194 Mega-Watt hours
x 50 US $ per megawatt hour ? = 29.4 million dollars per
year.
I invite checking of figures
LATER to
search: generators are not 100% efficient, but largely
so, no allowance deducted for that.
A big inefficiency would be if water was pumped up to a
canal above sea level, but some of that expenditure of
energy expense would be recovered on the Dead Sea end, as
extra drop height. & The pumps would be running on
cheap electricity supplied by the Dead Sea end.
if pipes too expensive. canals & viaducts (like
Romans used) across flat higher land if one used
electricity generated from the drop down to the red sea, to
power pump up from Mediterranean to canal.
LATER to
search: what are percentage efficiency losses in Large
generators & pumps ?
If 430 metre drop is too much for strength of pipes of
a syphon, no problem, either just use whatever drop is
optimal, either direct on to first generators, then venting
into a small lake then drop that water down another pipe to
another generator station. Or have a first small drop from
the syphon into a top pool, then pipe it in a drop down to
1st generators.
About 80 km between the Mediterranean & Dead Sea,
view maps:
Google and
openstreetmap
Pipe or canal Building Cost
High. Not worth figuring how high, until we've calculated
the value of electricity that could be generated. Only then
can a return on investment be calculated.
Alternate Tunnel building
cost.
At 80km, I guess a bit more than the 57 km https://en.wikipedia.org/wiki/Gotthard_Base_Tunnel,
depending on geology. OTOH a mere water tunnel wouldn't need
all the expense of 2 bidirectionals tunnels & a central
escape tunnel.
Whether a tunnel or a syphon (ie
sealed tube, with Dead Sea end lower than Mediteranen), some
gradient is needed to keep a pipe
flowing (& more gradient for more
speed).
Gradients from 1 in 40 to 1 in 110 will normally
give adequate flow velocities.
The above is for sewers containing solids (that
they recommend to start planning at 1 in 80)
But this Med-Dead Seas project is for clean sea
water, so take a guess at 1 : 200. 1/ 200 of 80 km =
80,000 / 200 = 400 metres. That's near all of the 430.5
m. level of the dead sea ! LATER to
search Hydrology : How flat can a tunnel or canal
of clean water run ?
Slope: 2023-09 I think I heard a German documentary say
Bazelgette discovered a slope of 40 cm per kilometer for
keeping sewage running for London.
Ref. also en .
wikipedia . org / wiki / Thames_Tideway_Scheme 25 km
long sewage tunnel under the Thames. From -30 m at Acton,
to -70 m at Abbey Mills. [ Are both negatives local
relative to local land or relative to a common sea level ?
ie Does that give us a slope/ gradient of 40m metres in 25 km ? Doesn't
seem enough for rain water, let alone sewage ? ]
LATER to
search: the larger the pipe, the more efficient: less
skin friction.
The bigger a canal is, the
less the gradient can be, as while
there is static friction at the edge, the water can run
faster in the middle (consider a river as a series of
concentric semi circles, with each slower moving layer
exercising friction on the next more central faster moving
layer).
Side Effects
Could either stop Dead Sea sinking, or could raise the
sea; stop or reduce ever more sink hole collapses; resume
old tourist trade on a stable coast line.
However maybe rain has leached out some salt column
support even up to old levels ?
Some of the water piped from the Med. could be
desalinated anywhere along the pipe line, using surplus
electricity from the Dead See generators, for agricultural/
industrial/ human use, anywhere adjacent to the Med-Dead
pipe line, or anywhere preferably downhill from where the
Med-Dead pipe delivers above the Dead Sea.
Local Climate mitigation around Dead Sea: delivering
water of either or both Med Sea salinity & potable
water would assist the arid desert type Dead Sea area.
Not damaging to world sea levels, it would fractionally
help mitigate against melting pole caps.
Routing planning & buildingof canal or syphon pipe
would need co-operation between jews, palestinians etc.
they would need reminding to co-operate, as if they fail to
agree, both sides will loose all benfits.
Politics
Israel & Jordan both adjacent to Dead Sea
should discuss & co-operate,
invite all locals to invest money &
labour,
invite also non local investors, as a moderating
neutral force intent just on engineering &
financial success, not aligned to local political/
national/ religious/ factions.
Consider securing a special status for the
territory of the canal/pipe, to secure co-operation
between rivals, & secure the operation. Consider
adopting some clauses from political arrangements of eg
Suez & Panama Canals & Straits of Bosphorus,
& Arctic Treaties etc.
