Ocean Gravitational Energy Storage Platforms

The affordable energy transition with ultra low cost electricity storage

* Lead acid batteries and pumped storage hydroelectricity = 200 €/kWh C. STEVENS - March 30, 2015

No technical barrier

(just assemble a barge, a hoist and steel tubes

filled with rubbles)

Energy efficiency

> 80% (total roundtrip)

20 times cheaper than competitors*

(Capex 10 €/kWh - 800 €/kW)

After several technical challenges, the ocean gravitational solution is ready for a demonstration with rough sea conditions (severaleters waves).

The prototype development is ongoing and the first fund raising starts in order to finance offshore subsea trials and communicate about the technical simplicity and the huge economical interest of this breakthrough innovation.

If you want to invest, we offer 10% of share capital to finance this key trial phase which will be decisive to open a real market for stationary storage.

Christophe STEVENS - Inventor of several solutions that help to strongly reduce the cost of energy storage for grid- In-depth knowledge of patent database concerning energy storage and renewable productions.- Discover the opportunity of Qattara dam in Egypt, in order to transform an expensive hydropower production project into a low cost hydro pump storage opportunity- Founder of Sink Float Solutions- Engineer (MSc Agro ParisTech)

Fabian HUGUET - Business Developer for Germany and Austria- Shareholder- Project management: Orange Money, Marc Picard Lineartechnik, BNP Paribas „Self Service“- Master in International Business Program (Reims Management School)

Mail: fabian.huguet@sinkfloatsolutions.com Cell: + 49 160 98 98 27 28

Our website: www.sinkfloatsolutions.com

We assume that it is possible to store electricity with a disruptive technology beeing both very simple and ultra low cost…

… in this document, we will demonstrate that it is possible.

1. How does it operates?

2. Why is it so low cost? How far are the competitors?

1. A prototype to validate with facts both technical feasibility and economic advantage.

2. Partnership => we are looking to key partnership (customer, supplier) => An opportunity exist untill May 29, 2015 (first fund raising for private companies to complete public subventions): We offer 10% of capital (european exclusivity on patents) for prototype funding and first offshore tests.

4000 meters(ocean depth)

150 meters

Pontoonbarge

Hoist

Treuil de guidage

Auto floating weights

Sea level

Sea floor

The barge and the main hoist (a double hoist)allow to generate a storage power of 25 MW(motor/generator connected to the hoist), byraising or descending weights one by one. Thebarge is connected to the grid through submarinehigh voltage direct current line (HVDC) notpresented on this view.

While in the « high level storage position » (nearsea surface), the weights are moored to a floatingpontoon. While in the « low level storageposition » (sea floor), the weights are left on thesea floor (bottom) against one an other, at 4000meter depth (13,000 feet). The black square onthe view presents the surface necessary forweight storage on the bottom.

A weight (with a 1200 cubic meter cavity) allowsto store 13 MWh. On 4000 meters, the cycle timeis 30 minutes (speed 8 km/h = 5 miles/hour). 144weights are necessary to store 25 MW of electricpower during 3 days.

With 8 km/h of vertical speed, the global roundtrip efficiency (including hydrodynamic forces) ishigher than 80%.

1.HOW DOES IT OPERATES?

For a solar electricity unit farm, the need of storage capacity would be 15 hours and then 30 weights would be enough. Only one of the 4 pontoons presented on this view would then be necessary. A solar farm of 250 MWp (capacity factor 10%) would cover a surface of 1 square kilometer.

The size of storage barge presented on thisview (25 MW) would allow to solveintermittency issue of 100 wind turbines of 1MWpeak each with a capacity factor of 25%.Such a wind turbine farm (100 MWp) wouldcover 10 square kilometers (4 square miles)

Pontoon

Barge (25 MW)

Auto floating weights (13 MWh/unit)

50 meters

30 meters

Even if the storage solution is offshore, it can also beconnected to grid and onshore wind turbine or solar farms

In the « high position », the auto floating weights are stored 40 meters below the surface of sea, in order to avoid theybump one another with a rough sea. Their cavity (1200 cubic meter capacity) is filled with air with the correspondingpressure of that depth (5 bars). With that depth level, the relative weight is 30 tons. The autofloating weight can be hangedto a 50 cubic meter auxiliary float through their secondary cable (such cable must resist to 30 tons).

Before starting the descent, the auto floating weights are detached from the auxiliary float and hanged to the hook of mainwinch through its main cable, such cable must resist 1200 tons, which correspond to the relative weight the autofloatingweight will tends towards, during the descent. Indeed, the depth increase (and pressure increase), water will enter thecavity through orifice, and compress the air inside the cavity so that air pressure will tend towards outside pressure,corresponding to the depth. There will have a constant equilibrium between the outside and inside pressure. The residualvolume for air, will reduce with exponential speed. At a depth of 400 meters (= 10 % of total depth), the volume filled withwater will already be of 90% of total cavity level, and then the relative weight (= 1080 tons) of autofloating weight will be90% of the maximal relative weight. (1200 tons). Indeed, at 400 meters depth (40 bars), the volume of air will be 120 cubicmeter, only 10% of initial volume because of the gas formula: PxV=constant. If you multiply the pressure by 10, you have todivide the volume by 10. At 4000 meters, the air « bubble » will have a 3 cubic meter volume, it could be confined in a smallreservoir situated upside the cavity in order to avoid air diffusion into the water. This phenomenon is proportional to thepressure. And then it is possible to reduce the frequency of reloading the system with air (maintenance cost).

Prototype 2,5 to 25 kW

CAM

Thruster mode to ease the operations

Hydrokinetic turbine mode to reloadbattery during vertical movements

The thruster hook is one of the numerous solutions to ease the weight change operations, near the sea floor …

Battery

Prototype 25 kW

Industrial scale: 25 MW or more (13 MWh/ weight)

Autonomous ancillary float is an other solution and might help avoiding to anchor pontoons if 50 meters deep water flow is low enough. The cost

estimation includes both autonomous float and pontoon.

1200 T

1170 T

27 T

27 T

Buoyant force

Absolute weight

Tension force into the cable

+3 T = horizontal force of traction projected on cable axis.

0,5 T = drag

0,5 T = motor traction(motor 10 kW)

In order to adapt the length of the cable of the hoist to the distance from the barge to the low point, the barge comprises acompensation cable length device. This allow to adapt to the temperature variation affecting the cable length, the possiblevariable inclination of cable (water flow), etc.

It is also very helpful to operate slow vertical movements of hook while those are close to the sea floor and/or sea level,and the main motor/generator is stopped.

An ancilliary storage device will supply storage powercapacity when the main motor/generator is stopped(during the weight change step).The ancilliary storage capacity need is only 60 secondswhich is very small by comparison to the 3 days capacityof 144 weights (hypothesis: 30 min cycle time, 4000 meters

depth , 8 km/h vertical speed).Then it is possible to use different ancilliary storagesystems even if those have an expensive unit cost(€/kWh) like flywheels or single weight/high speed hoist(prensented on this view)

An other option to manage the time the hoist can notoperate (due to weight change every 30 minutes) => useat least 2 barges with 15 min cycle difference andincrease the speed (power) of one barge while the otheris changing weights.

Reinforced concrete base Mixture of dense and

low cost materials (stones, rubble, sand, clay).

Steel tube (cavity)

Openings to allow water flowing in/out of the cavity

While stored on the sea floor, the weight is almost full of water and the air is compressed to 400 bars. With such a pressure, and during a long period in deep water, the air can diffuse inside the water (Henry law). In order to reduce this phenomenon, and the energy cost of filling compressed air in the cavity after eachcycle, the small air volume can be stored in a confined area in the upper side of the weight.

During the descent phase, due to compression, the air temperature will increase. Then heatwill be lost while the weight will be cooled by water temperature.During the ascent phase, due to expansion, the air temperature will drop and the volume of air will not be enough to make the weight float. Several solutions exist (patent technologyavailable on request)

The important thing is that even if 100% of air was lost and had to be injected after each storage cycle, the global energy cost of this would not exceed 2 to 3 % of global energy efficiency. A compressed air buffer reservoir and compressor on the barge can help to reduce the time for filling the air, after eachcycle.

Intellectual property: key aspect, last updates anterioritystudies (2015), and breakthrough position of our solution

=> available upon request

The auto floating weights presented above is the basic solution that helps to do a quick theoretical demonstartion of both technical feasibility and economicadvantage.

Meanwhile, our patents includes others designs of « auto floating weights » in order :To improve hydrodynamicTo eliminate the gas into liquid diffusion phenomenon (Henry Law)To reduce cost of auto floating weightsTo increase life time duration of auto floating weightsTo improve resistance while auto floating weights are dropped on the sea floor.To ease operations

To position our solution as free of other intelectual property rights and offer the best advantages for all key performance aspects.

Assembling technologies mature for more than 100 years (barge, hoists, motor / generator, steel tubes filled with rubbles looking like tower storage tanks). Fine tunning with conventional offshore engineering (thrusters, deep water camera)Low cost materials: steel, concrete, rubbles, …

CONCLUSION:THERE IS NO TECHNICAL BARRIER TO OUR SOLUTION

We are building small scale prototypes in order to validate the different process steps with facts, even with a rough sea. Extrapolation of huge masses inerty and impact on speed of weight change operations are already carried out: Less than 60 seconds will be necessary for horizontal movements operations and vertical acceleration/deceleration.

2.WHY IS IT SO LOW COST?

Our solution is low cost because:

We use low cost materials (unlike chemical storage)

We use huge depth (4000 meters) which is free in the ocean (unlike pump hydro)

Global cost (including HVDC and O&M) are several times smaller than the gap cost with competitors.

1) A quantitative demonstration by simple, intuitive analogies is presented here below

2) A quantitative demonstration with detail of calculations and hypothesis is available on request.

Pumped storage hydroelectricity Auto floating weights

barge

hoistAuto floating weights

Turbine / pump

Pipe or tunnel

Capex power (€/kW)

Capex energy (€/kWh)

Water

Topography

Water retain concrete, rubbles and steel (buoyancy force)

Concrete,rubbles and steel retain

the water

Important but free

Small

Can be small

Must be important

34 Mm3(water downstream)

44 Mm3(water upstream)

14 Mm3 (dam)Δh =380m

Exemple: Bath County PHS 3,2 G€ (equiv. 2014) 30 GWh of capacity (10h, 3 GW) = 105 €/kWh

The fact shows that even the mostcompetitive PHS use the same mass of materials in the bigger dam than water in the smaller reservoir (downstream here)

Two oppostite ways to use gravity for

energy storage

Autofloating weights are made of rubbles (90%), concrete (8%) and steel (2%)

Other existing PHS cost from 70 to 200 €/kWhCoo PHS (Belgium) = 120 €/kWh (estimation)

Lead acid batteriesAuto floating weights

1200 Tons @ 4000 metersEpot = m*g*h = 1200000*9,81*4000 = 47 GJ = 13 MWh

Lead acid batteries are still the main technology used for micro grid storage applications (because lead is much cheaper than lithium, antimony, etc)

ADEME (nov 2013): 100 €/kWhENS (accumulateur Pb = 30 Wh/kg)

Life time duration: 5 years

600 Tons of lead would be necessary to store the same quantity of energy (13 MWh) than 1200 T of auto floating weight (which is made of rubble, concrete and 2% of steel)

Even if weight was made of 100% of steel, our solution would be more competitivethan battery because steel is much cheaper than lead (more than 2x cheaper), and a much better duration.

Reinforced concrete base150 m3

Mixture of dense and low cost materials (stones, rubble, sand, clay). 2500 T (850m3)

Steel tube (cavity)3,4 m3 = 27T

90k€/13MWh< 10 €/kWh

Life time duration: >> 20 years

Beyond rawmaterial cost

barrier*

*raw material costs are strongly affected by mining costs which are strongly affected by energy costs which …

Summary:

Components which cost are proportional to storage power (Capex €/kW) The barge PulleysWinch cables Electric components

(motor/generator, converters, etc)

Components which cost are proportional to storage capacity (Capex €/kWh of storage capacity)Weights (rubble, sand, concrete, steel plates)Anchoring cablesPontoons (used tyres and plastic bottles, cables) 10 €/kWh

800 €/kW

Demonstration files (hypothesis, calculations,

etc) => available uponrequest

Intellectual property: key aspect, last updates anteriority studies (2015), and breakthroughposition of our solutions => available upon requestThermicHydrodynamicRough sea flexibility: 10 m waves operabilityLife time, grey energy, raw materials, etcAuto floating weights variants

MARKET

Main Customers:WindNuclearSolar

Main Suppliers: Offshore and ship building engineeringGas plants and diesel generators*HVDC submarine cable

* Best economic compromise for full wind turbine scenario is 1 day of storage capacity + 2 weeks/year of gas/diesel and not 3 days of storage)

PARTNERSHIP STRATEGY

We are looking for partners interested by developing such a solution as engineering service supplier, component suppliers, customer (electricity producer or distributor).

THE PRESENT PHASE: prototype under construction for demonstration

THE NEXT STEP OF THE PROJECT is to build a large scals prototype and connect it to a wind farm, solar power station, or a nuclear plant.

Prototype P1 (reference scale 1/1)Storage power: 25 MW (hoists)Capacity: 13 MWh/ weight (1200 T)Depth: 4000 mVertical speed: 8 km/hCycle time: 30 minBarge dimension: 40 m x 40 mWeight dimension: 10 m x 30 m

Prototype P10 (scale 1/10)Storage power: 2,5 kW (hoists)Capacity: 1,3 kWh/ lest (1200 kg)Depth: 400 mVertical speed: 0,8 km/hCycle time: 30 minBarge dimension: 4 m x 4 mWeight dimension: 1 m x 3 m

Prototype cost:30 €/kWh+ 25 M€

Industrial cost:10 €/kWh450 à 800 €/kW

Prototype cost950 €/weight *(=72 €/kWh extrapol. 4000 m)60 k€ *(shuttle, bargeand hoists)

20x cheaper than competitors (pumped storage hydro and lead batteries)

The prototype willhave a competitivecost unless no scale economies, prudent safety factors(oversizing) and highunit cost for proto components.

P1 and P10 prototype objective = economic advantage demonstration (and technical feasibility)

Which size for a prototype?

*The costs include components cost (no engineering , no submarine electric cable)

+ 2 ROV (rental)

Scale effect: Power 4

Height x10Length x10Width x10

Volume x1000

Depth x 10

Storage capacityx10 000

Scale 1/10 x 104

Proto P10 => 2,5 kW x 104

Proto P50 => 4 W x 504 25 MW

Storage power

Cost => x 103

NB: P10 proto, -We oversized the pulleys and reductor gear box of hoists in order to have equivalent ratio of cable mass/weight mass than P1 dimensions. -We propose to use a 25 kW motor/generator (unlike 2,5 kW), in order to make some tests with 8 km/h vertical speed and validate hydrodynamic calculation and kinetic energy calculation of moving parts (cable, weight, pulleys, etc)The cost estimation in the previous slide includes those oversizing. ..The prototype should operate with a sea waves force several times higher than extrapolation max capacity and thenease the demonstration of >>90% operation ratio for an industrial scale platform. (no oparations < 4 weeks/year whenrough sea)

More info about our sea test protocol and demoprototype dimensions available on request

0 2 4 6 8 10 12 14 16

STEP (150 €/kWh)

Batterie Pb ac (durée de vie 20 ans)

Lac Leman - 5 km - 300 m

Lac Titicaca - 30 km - 280 m

Lac supérieur USA - 100 km - 400 m

Grands lacs (Afrique) - 100 km - 1000 m

Lac Baikal - 30 km - 1600 m

Mer Noire (Sébastopol) - 60 km - 2000 m

Chennai - 65 km - 3000 m

Shanghai - 660 km - 2000 m

Abidjan - 72 km - 2000 m

Salvador da Bahia - 50 km - 2000 m

Seatle - 150 km - 2000 m

New York - 270 km - 2000 m

Tokyo - 215 km - 8000 m

Tokyo - 64 km - 2000 m

Lisbonne - 179 km - 5000 m

Lisbonne - 84 km - 2000 m

Grèce - 80 km - 5000 m

Rome - 200 km - 2500 m

Rome - 123 km - 2000 m

Allemagne - 1400 km - 4000 m

Belgique - 1000 km - 4000 m

Toulon - 226 km - 2800 m

Toulon - 20 km - 2000 m

Bordeaux - 320 km - 4000 m

Bordeaux - 100 km - 2000 m

Bretagne - 350 km - 4000 m

Scénario "D" - 150 km - 4000 m

Total investment (G€) for 1 GW production without shortage with 4 GWp of wind turbines

Eolien terrestre (fc 25%)

Gaz (GE)

Stockage P (barges)

Stockage E (lests)

HVDC

Stockage batterie

Stockage STEP

Those modelings show that the best compromise must be analyzed on a case by case basis.

Even if storage cost (weight) was multiplied by 5, the ocean gravity solution would remain more competitive than batteries. Similar situation for HVDC costs

The solution remain competitive even for several hundreds of meters depth.

Onshore wind (cf 25%)

Gas or diesel generator

Storage P (barge)

Storage E (weights)

HVDC

Lead acid

Hydro pump

Example of cost structure by markets(for an onshore wind turbine dominant mix scenario)

HVDC cost estimation = extrapolation of Norned cost (incl. cable + converters)

With an investment cost lower than 10€/kWh of storage capacity, the storage for grid will allow tostrongly accelerate the development of new energy mixes including renewable and/or nuclear. Theenergy storage market will then be determined by the energy production solution choice.

-A mix with majority of wind turbine will need an average of 3 days storage capacities-A mix with majority of solar solutions will need an average of 15 hours of storage capacities.-A mix with majority of nuclear plants will need an average of 8 hours of storage capacities

It is possible to strongly reduce thestorage capacity need by using a mix withthermal peak plants (gas, coal, bio fuel),which capacity factor will be very low (15days per year) and then authorizing theinvestment of low cost peak plants (likegas genset) even if their energy efficiencyis bad and if the combustible is expensive.

Thermal peak plant need

Storage cost gains

This modeling was realized by extrapolating the wind production during 2013 in France and by using the following hypothesis: 100 % wind production and storage stations. The nb of blackout days (when it is not zero) indicate the need of thermal plant use. The energy efficiency of storage device used for this modeling was 80%, so that explain why if we don’t increase the production capacity by comparison to the need, there will be always a blackout situation regardless the storage capacity .

Nb of days without blackout

Production capacity increase by comparison to average consumption

Number of storage capacity days available

Our proposed solutions for low cost storage

CAPEX yld. Annoyance Eligible site ConclusionEnergy Power

Batteries (Pb ac) 500 €/kWh

(20 ans)

N.A. 70% Contamination Unlimited Too expensive to allow other solutions than thermic plantswhile developing strongly low carbon production system (wind turbine, solar, nuclear) . It would be necessary to invest2 to 4 times in storage capacities than in production capacities (with PHS) and 8 times (with batteries). Hypothesiswind turbine: capacity factor = 20%, cost = 1,4 M€/MWp

Batteries (other) Too expensive for stationnary storage

Land PHS 150 €/kWh

150 €/kW

70% Land use competition

Emergingcountries

Maritime PHS (7 km dam)

200 €/kWh

300 €/kW

60% Maritime trafficcompetition

Only possible in North Sea

Maritime PHS (50 km dam)

30 €/kWh

300 €/kW

60% Maritime trafficcompetition

Only possible in North Sea

The breakevent point for such storage solutions, makeneccesary to use a minimal storage capacity of 300 to 2700 GWh/PHS, equivalent to 9 G€ of investment for 12,5 GW,which allow to store the equivalent of 6000 wind turbines of 2 MWp each, which is 25% of the electric consumption of a country like Belgium (by considering a capacity factor of 20% for wind turbines).

Maritime PHS (150 km dam)

10 €/kWh

300 €/kW

60% Maritime trafficcompetition

Feasibility to demonstrate

Egyptian PHS (Qattara depression flooding)

5 à 10€/kWh

300 €/kW

60% 300 inhabitants to compensate

Only in Egypt Minimal investment etimation = 15 G€ for the tunnel between Mediterranean Sea and the dam to separate the depression into 2 reservoirs (on the topographic bottleneck) It would corredpond to 3 TWh of capacity.

CAES C4U 3 à 60 €/kWh

1000 à 4500€/kW

50 à 70%

No Unlimited The only solutions offering simultaneouslyinteresting costs, energy efficiency and massive development potential. OGES (gravity potential

presented in this doc)10 à 100 €/kWh

450 à 800 €/kW

80% No Unlimited

New technologies of the future, will have strong difficulties to overcome raw material cost market laws while those costs (mining) are strongly affected by energy cost…

… and conventional technologies suffer from too high cost for massive storage developement, with the exception of scale effect low cost hydro pump stations (but only possible in North Sea or Qattara depression (Egypt).

Tunnel investment < 14 G€600 m3/sec (2 times evaporation speed), 3 times Gothard Tunnel volume excavation)

Upstream reservoir: 4000 km 2 + 20 m av. water height = 10^11 m3

Mediterranean Sea(80 km)

Downstream reservoir 3000 km2 + 20 m av. water height = 0,6*10^11 m3

5 km10 km 40 km

50 m

25 m

= 70 Mm3 of embankment dam

Dam investment +/- 1G€

(3,4 TWh) = 45 GW of pumping & turbines for 3 days of storage)

20 m

Qattara hydro pump project (Egypt): A mega project that might be economicallyinteresting but offering no small scale development: 100 GWpeak of wind turbineand/or solar station would be necessary to justify the full storage capacity. Suchrenewable production would correspond to 30% of electric consumption of acountry like Germany, or North Africa 2015 electric consumption.

First discovery of hydro electricity production potential : Pr Penck 1912.First preliminary feasibility study and macrocalculation for electricity production potential = 300 MW : Pr Bassler 1964.First discovery of multi TWh storage potentialwith dam construction in the topographicbottleneck : Christophe Stevens, 2014.