The document describes a hydraulic hydro storage system that stores energy by pumping water into an underground cavity, lifting a rock cylinder and storing potential energy. When energy prices are high, the storage discharges through a power converter. Key advantages are large storage capacities over 1000GWh with known technologies at a cost that drops significantly with increasing radius. The system uses no chemicals and has a small surface footprint with minimal environmental impact.

1. Hydraulic Hydro Storage System
Prof. Dr. rer. nat. Eduard Heindl Furtwangen University

2. Hydraulic Hydro Storage System
Operation Principle
power grid r
E~r4
2r
connect
power hmax=r
capacity
converter
o Water is pumped into a subsurface cavity, using cheap electrical power
o The rock cylinder is lifted by hydraulic forces
o The storage is discharged when the energy price is high, using a power converter

3. Hydraulic Hydro Storage System
Physical Properties
r mass ~ r³
maximum heigth ~ r
l=2r
storage capacity:
h=r
E = 2 π g ρ * r4
surface ~ cost ~ r²
advantage cost per kWh capacity ~ 1/r²

4. Hydraulic Hydro Storage System
Construction
construction
road
1kr
2
m
1. tunnel mine shaft
2. tunnel
base tunnel,
water intake

5. Hydraulic Hydro Storage System
base plate seperation
mined space
waterproofing
base-tunnel excavated 2. tunnel
exca-
material vator
waterproofing
side view

6. Hydraulic Hydro Storage System
base plate seperation
base-tunnel
cutted
excavated rock
material
rock
exca-
vator
2. tunnel
top view!

7. Hydraulic Hydro Storage System
base plate seperation
base plate seperated
zylinder is monted on a ballast bed
waterproofing
base-tunnel excavated 2. tunnel
material
waterproofing
side view

8. Hydraulic Hydro Storage System
Drilling
drilling guide holes for the wire saw

9. Hydraulic Hydro Storage System
Diamond wire sawing
surface drilling holes
traction
rock
cut surface
r Diamond
wire saw
1. tunnel
side view

10. Hydraulic Hydro Storage System
utility
tunnel
Due to rock mechanics,
it is neccessary to cut a
V-shaped trench
sawing string
rock mass
utility
tunnel
boulder
side view

11. Hydraulic Hydro Storage System
utility
tunnel
trench will get smaler
due to rock pressure
geo-
membrane
every surface is sealed
using geomembrane rock mass
utility
tunnel
side view

12. Hydraulic Hydro Storage System
Sealing and Securing
rock securing
sealing ring
metal
floating piston
Sealing
to keep cylinder
rock dry capacity filled
with water

13. Hydraulic Hydro Storage System
Sealing O-ring
steel
steel pin joint with
cover
cover steel sensor
rock mass wa
te
rp
re podest
ss
ur
e
seal
piston

14. Hydraulic Hydro Storage System
Setup: multi O-ring sealing
rock
v
podest
pressure: 10 Bar per O-ring
pressure: 10 Bar per O-ring v
v
piston

15. Hydraulic Hydro Storage System
Safety
There should be systems, that stop a leakage by physical means
self inflating
in case of 1. backup
water contact sealing ring
floating piston
blocking in
case of high 2. backup
flow cylinder sealing ring
capacity filled
with water

16. Hydraulic Hydro Storage System
Investment for r=500 m HHS
10.000
tunnel €/m 73 Mio. €
drilling 500 €/m 157 Mio. €
wire saw 10 €/m² 63 Mio. €
overburden 20 €/m³ 126 Mio. €
base seperation 1.000 €/m² 785 Mio. €
seal (stainless steel) 200 €/m² 157 Mio. €
seal geomembrane 100 €/m² 393 Mio. €
10.000
O-ring €/m 31 Mio. €
Summe 1.785 Mio. €

17. Hydraulic Hydro Storage System
Technical and Financial Data*
Radius [m] 62,5 125 250 500
storage capacity [GWh] 0,5 7 100 1600
pressure [Bar] 25 50 100 200
Investment² [Mio. €] 40 112 400 1800
Investment
per kWh [€] 80 16 4 1
value of one loaded
system 100€/MWh [Mio. 12 200
€] 0,05 0,800
ROI [# of cycles] 800 140 33 9
*figures rounded
²invest does not include pumping system

18. Hydraulic Hydro Storage System
Advantage
storage capacity beyond 1000 GWh visible
efficiency: 80% known value
no resource problem
no mountains neccessary
no enviromental problems, because no chemicals needed
only small footprint (up to 2 MWh/m²)
less water consumption than PHS (~1/4)
known technologies
price drops with 1/r²

19. Hydraulic Hydro Storage System
Thank you!
www.Hydraulic-Hydro-Storage.com

20. Hydraulic Hydro Storage System
contact
Furtwangen University
Prof. Dr. Eduard Heindl
Robert Gerwig Platz 1
78120 Furtwangen
Germany
+49 177 2183578
hed@hs-furtwangen.de
www.hydraulic-hydro-storage.com