Alice Hub PHES — Australia’s Continental Energy and Water Engine

40 GW of pumped hydro at 770 m head in the MacDonnell Ranges. A 32-day sovereign energy reserve. Up to 25,000 GL per year of water to southern Australia. The national endowment that turns sun waste into energy security, water security, and inland prosperity — simultaneously.

Memo5 — Energy & Water
AuthorBrett Murrell
Versionv1.0
Date12 May 2026
SeriesMMA Memos
Word count~6,800
Alice Hub is not a power station. It is a continental endowment. Seven natural gorge pairs in the MacDonnell Ranges west and east of Alice Springs form the world’s largest pumped hydro energy storage system — 40 GW of generation capacity, 16,000 GL of water storage, 770 m of head, and approximately 30,886 GWh of usable energy. That is a 32-day sovereign energy reserve for the entire Australian grid at full discharge. Water arrives from the north via the MMC-VA aqueduct corridor using excess solar power that would otherwise be curtailed. Water flows south and east by gravity to inland towns, southern farmers, and the Murray-Darling basin. A Northern and Inland Flood-Harvesting Diversion System can lift annual water throughput from 10,730 GL to 25,000 GL or beyond. The system simultaneously hosts AI hyperscale computing, supports Indigenous economic sovereignty, anchors the continental defence logistics backbone, and delivers an estimated $1.33/kWh storage cost — 25 times cheaper than Snowy 2.0.
40 GWPumped hydro capacity
32 daysSovereign energy reserve at full discharge
$1.33/kWhStorage cost — 25× cheaper than Snowy 2.0
25,000+ GLAnnual water throughput with flood harvesting

1. Not a Battery. A Continental System.

The Alice Hub Pumped Hydro Energy Storage system is the energy and water centrepiece of the SBC programme. It is not a conventional pumped hydro plant scaled up. It is a continental-scale system that operates simultaneously as the world’s largest energy storage facility, the world’s largest flexible grid load, and the continental water reservoir delivering water security to inland and southern Australia.

The system uses seven gorge pairs in the MacDonnell Ranges — natural high-head storage sites identified in the ANU STORES atlas — as upper reservoirs, with lower reservoirs constructed at the base of each gorge. The 770 m head differential between upper and lower reservoirs drives the turbine-generators in discharge mode and defines the energy density of the storage system.

Water arrives at Alice from the north via the MMC-VA Level 2 aqueduct corridor — a 17 m × 10 m sealed pressurised conduit running the full Darwin–Alice corridor, powered by excess solar generation from the corridor’s HVDC system. Water is distributed south and east from Alice by gravity, through the same conduit system in open-channel mode, to southern farmers, inland towns, and corridor communities.

In 1938, John Bradfield proposed diverting Queensland coastal rivers inland to water the continent. The MacDonnell gorges are exactly the storage sites the Bradfield Scheme lacked — natural high-head reservoirs ready to receive continental-scale water flows. The SBC programme builds the Bradfield vision using 21st century technology: solar power, the MMC-VA corridor, and PHES turbines instead of steam pumps and open canals.

2. The System at a Glance

ParameterValueNotes
Total storage volume16,000 GLAcross 7 gorge pairs (A–G) in MacDonnell Ranges
Average head770 mBetween upper gorge reservoir and lower reservoir
Energy storage (programme-locked)~30,886 GWhAt 770 m avg head, 80% round-trip efficiency, average operating conditions
Generation capacity40 GWAll 7 gorge pairs at full output
Full discharge duration32 daysAt 40 GW continuous generation
Normal pump load15–20 GWExcess solar absorption — grid stabilisation
Aqueduct design flow340 m³/s17 m × 10 m conduit at 2.0 m/s design velocity
Annual throughput (base)~10,730 GL/yearContinuous design flow
Annual throughput (with flood harvest)15,000–25,000+ GL/yearNorthern and inland diversion system active
Turbine typeFrancis reversibleStandardised across all 40 GW — bulk procurement, simplified maintenance
Fast response BESS alongside500 GWhLithium — sub-second response; PHES handles sub-minute and beyond
Total marginal capex~$29–53BAll 4 phases — full continental system
Levelised storage cost~$1.33/kWhvs Snowy 2.0 ~$34/kWh — 25× cheaper per kWh

3. The Aqueduct — MMC-VA Level 2

Water reaches Alice Hub via the MMC-VA Level 2 aqueduct — the second deck of the Big Bertha five-level viaduct, a 17 m × 10 m sealed pressurised conduit running the full Darwin–Alice corridor. This is not a dedicated pipeline. It is an integrated service deck on the MMC-VA structure, sharing the corridor’s structural system, maintenance access, and HVDC power supply.

ParameterSpecificationNotes
Conduit cross-section17 m × 10 m = 170 m²Full MMC-VA corridor width and 10 m depth
Design velocity2.0 m/sConservative — limits erosion and head loss
Design flow rate340 m³/sAt 2.0 m/s through 170 m² section
Annual throughput (design)~10,730 GL/yearContinuous flow — significantly exceeds Alice Hub fill rate
Pumped mode (north → Alice)Sealed pressurisedPowered by corridor HVDC — excess solar at zero fuel cost
Gravity mode (Alice → south)Open channelLid panels removed — gravity flow at corridor slope
Pump power required~2.92 GWAt 743 m total dynamic head (500 m static + 243 m friction)
Pump stations~25–40 stationsEvery 50–100 km; co-located with MMC-VA corridor; HVDC powered
Pumping hours/day6–10 hrs excess solarPart-time pumping sufficient — gorge storage is the buffer

The conduit does not need to pump continuously. The gorge pairs are the buffer. When solar is generating excess power — typically 6–10 hours per day in central Australia — the pumps run at full capacity. The gorges absorb the daily inflow. The PHES turbines can discharge at 40 GW at any time, day or night, independent of pumping. The conduit is the tap; the gorges are the tank.

4. Northern and Inland Flood-Harvesting Diversion System

The base aqueduct design delivers 10,730 GL/year. The Flood-Harvesting Diversion System can more than double this by capturing excess wet-season flows that currently run to the sea or spread across floodplains with no capture. The design principle is explicit: flood harvest only — capture excess peaks without affecting normal river ecology, base flows, ecosystem function, or cultural water rights.

ComponentDetail
Northern corridor branches3 branches capturing wet-season surplus from northern river systems
Inland river off-takes6–10 targeted captures from inland river systems during flood peaks
Structures12–18 low-impact weirs, buffer storages, and pump stations
Construction integrationBuilt in parallel with MMC-VA corridors using the same heavy-lift logistics
Cultural and ecological protectionBase flows, ecosystems, and cultural rights fully protected — flood harvest only

4.1 Water Throughput Sensitivity

ScenarioAnnual throughputConditions
Base (aqueduct only)10,730 GL/yearContinuous design flow — no flood harvesting
Moderate (3 northern corridors)15,000–17,000 GL/yearNorthern wet-season capture active
Optimised (full system)20,000–25,000+ GL/yearAll northern and inland captures active in good wet season

At 25,000 GL per year, Alice Hub delivers more water than the entire current Murray-Darling annual flow — drought-proofing southern agriculture, enabling new agrivoltaic development across 13.4 million hectares, and refilling the inland river systems that have run dry under a century of over-allocation.

5. Energy Storage — The Physics

5.1 How Much Energy Is Stored

The theoretical energy content of 16,000 GL at 770 m average head is approximately 120,859 GWh. At 80% round-trip efficiency (pump-up then generate-back), usable storage at maximum fill is approximately 96,687 GWh. The programme-locked figure of ~30,886 GWh represents average operating conditions — the system is not always full, and effective average head varies with fill level across the seven gorge pairs.

PhaseStorage volumeUsable energyNotes
Phase 1 (commissioned)200 GL~386 GWhImmediate grid contribution on commissioning
Phase 26,600 GL~12,742 GWhExceeds Snowy 2.0 total target (350 GWh)
Phase 312,400 GL~23,928 GWhContinent-scale sovereign energy reserve
Phase 4 (full system)16,000 GL~30,886 GWh avg32 days at 40 GW — world record by every metric

5.2 Discharge and Refill

ScenarioPower outputDurationNotes
Full discharge40 GW~32 daysAll 7 gorge pairs at maximum output
Normal discharge20 GW~64 daysHalf capacity — routine grid support
Phase 1 only2.5 GW~26 daysFirst gorge pair commissioned
Frequency control0–40 GWSecondsSub-minute response with BESS support
Black start~500 MWIndefiniteGrid restart — no external power needed
Refill scenarioPump powerFull refill timeNotes
Normal solar excess~15–20 GW~65–86 daysSeasonal — summer solar peak fills gorges
Maximum pumping~40 GW~31 daysEmergency mode — all capacity pumping
Aqueduct continuous top-up~2.92 GW~545 daysNorthern water continuously replenishing via conduit

6. Dual Purpose — Energy and Water Together

The Alice Hub PHES operates simultaneously as an energy storage system and a continental water distribution hub. These two functions are complementary, not competing. Water pumped uphill stores energy. Water released downhill generates energy. Net water delivered southward provides continental water security.

ModeGrid functionWater function
Charging (pumping)Absorbs excess solar generation — prevents curtailment, stabilises frequencyAccumulates continental water reserve in gorge system
Discharging (generating)Dispatchable firm power — any time, day or night, black start capableNet water moves downhill — available for southern distribution
Water export (gravity)None — gravity flow uses no powerDelivers water to southern farmers, inland towns, Murray-Darling
Frequency controlPrimary frequency response — continental grid anchorMinimal water movement at frequency control timescales
Baseload generationFirm baseload — fills gap when solar and wind are lowSlow managed drawdown — maintains minimum reserve

6.1 Where the Water Goes

DestinationVolumeBenefit
Alice Springs and region~10–20 GL/yearPermanent water security for central Australia
Inland corridor towns (MMC-VA)~50–100 GL/yearWater supply for 200 corridor towns along the viaduct route
Southern farmers (SA/NSW/VIC)Hundreds to thousands GL/yearIrrigation, drought-proofing, new cropping areas
Murray-Darling connectionEnvironmental flows TBDInland river system regeneration via Lake Eyre basin connections
Agrivoltaic zones (13.4 M ha)Distributed tap-offWater for solar farm agrivoltaic agriculture along corridor

7. Phased Build Schedule and Capex

PhaseTimelineScopeCapacityEst. CapexKey milestone
Phase 1Years 1–5Gorge A + Northern Corridor 1 + initial diversions2.5 GW$4–8BFirst power + flood capture testing. Revenue from frequency market.
Phase 2Years 5–8Gorges B & C + Corridors 2 & 3 + inland Phase 115 GW total$12–20BExceeds Snowy 2.0. Water export to SA begins.
Phase 3Years 8–12Gorges D & E + full inland captures30 GW total$12–20BWorld’s largest energy storage. Full HVDC integration.
Phase 4Years 12–15Gorges F & G + optimisation40 GW$9–20B32-day reserve + maximum water security achieved.
Total15 yearsFull continental system40 GW / 16,000 GL$37–68B$1.33/kWh — vs Snowy 2.0 ~$34/kWh

The cost advantage is structural, not optimistic. Natural topography replaces deep tunnelling. Productised modular construction (standardised Francis reversible turbines across all 40 GW) enables bulk procurement and simplified maintenance. Corridor logistics built for the MMC-VA viaduct serve the PHES build simultaneously. Snowy 2.0 cost overruns trace directly to the deep-tunnel risks that Alice Hub avoids by design.

Phase 1 alone — $4–8B for 2.5 GW of firm dispatchable power — delivers comparable output to Snowy 2.0’s full capacity at 10–20% of Snowy 2.0’s cost. Phase 1 justifies the entire programme. Each subsequent phase adds capacity at marginal cost with no additional infrastructure establishment cost.

8. World Scale Comparison

Project / SystemPowerStorageHeadDurationNotes
Alice Hub PHES (proposed)40 GW~30,886 GWh770 m32 daysWorld record — all categories
Fengning, China — world #1 PHES3.6 GW40 GWh425 m~11 hrsAlice Hub = 11× power, 770× storage
Snowy 2.0, Australia2.0 GW350 GWh~700 m~7 daysAlice Hub = 20× power, 88× storage
Bath County, USA3.0 GW~24 GWh385 m~8 hrsLargest US plant
Gordon Dam, Tasmania0.43 GW12 GWh140 m~28 hrsLargest existing Australian PHES
All global PHES combined (2025)~200 GW~9,000 GWhVariousVariousAlice Hub = 20% of world total power; 3.4× world total storage
Tesla Megapack Hornsdale (SA)0.15 GW0.19 GWhN/A~1 hrBenchmark BESS — Alice Hub = 163,000× storage

The comparison table does not fully communicate the scale differential. Alice Hub at 30,886 GWh is not a larger version of existing PHES plants. It is a categorically different class of infrastructure — measured in days of national grid supply rather than hours. At 32 days of continuous 40 GW output it is a sovereign energy reserve, not a grid balancing tool. No other country has built anything remotely comparable.

9. If Not This, Then What?

Every energy policy involves a choice. The comparison below uses the same timeframe and comparable capital to show what Australia gets from each path.

OptionEnergy durationWater deliveryCapex efficiencyFirst power2050 outcome
Alice Hub + MMC32 days15k–25k+ GL/yr$1.33/kWh5 yearsTransformed nation
4-hour batteries2–4 hoursNoneHigher per kWh1–2 yearsPeak shaving only
Additional Snowy-style PHESLongMinimal~$34/kWh10–15 yearsIncremental gains
NuclearRigid baseloadConsumes water$250–400B+15–20+ yearsToo slow
Gas + importsShortNoneVolatile pricing3–5 yearsStatus quo dependency

Alice Hub + MMC delivers multi-purpose outcomes — energy, water, agriculture, jobs, defence, AI hosting — in the same timeframe and with comparable capital as today’s fragmented approach. The alternatives solve one problem at significant cost. Alice Hub solves five simultaneously.

10. The Sovereign Dividend — What Australia Gets

Alice Hub is a high-multiplier national platform. Benefits compound across energy, water, economy, society, and strategy. Direct financial returns include energy sales, frequency control and inertia services, water delivery contracts, and AI hyperscale take-or-pay arrangements — targeting 8–12% inflation-hedged returns appropriate for superannuation fund investment.

10.1 Energy Security

Cheap firm power for the continental grid. A 32-day sovereign energy reserve — meaning Australia can run its grid for over a month with zero sun and zero wind before the reserve is exhausted. Primary frequency response and black-start capability anchoring the continental grid. Elimination of the baseload gap that has plagued the renewable transition.

10.2 Water and Agriculture

Drought-proof water supply to the Murray-Darling system — protecting an estimated $22B+ of annual agricultural GDP. New desert food bowl enabled by agrivoltaic development across 13.4 million hectares along the corridor. Permanent water security for Alice Springs, central Australian communities, and 200 corridor towns. Inland river system regeneration via Lake Eyre basin connections.

10.3 Economic and Industrial

AI hyperscale compute hosting — Australia’s cool nights, renewable power, and massive water supply for cooling make Alice Hub the natural site for Asia-Pacific data centre infrastructure. Manufacturing renaissance enabled by cheap firm power. Inland towns revived by corridor activity, water access, and agrivoltaic farming. Transport corridor efficiencies from the MMC-VA viaduct itself.

10.4 Indigenous Sovereignty

A 2.5% gross revenue royalty paid into a Sovereign Wealth Fund governed by Traditional Owners. Free base-load power to remote communities — eliminating diesel dependency. New education and health infrastructure co-located with corridor facilities. Co-design with Arrernte Traditional Owners as an essential precondition for any development — not an afterthought.

10.5 Strategic and Defence

Defence logistics backbone for central Australia — the MMC-VA corridor is a strategic asset for fuel, water, and rapid equipment movement. Reduced fuel import dependency. Australia as Asia-Pacific energy bridge — exporting sovereign renewable power and AI compute to regional partners. Space and observatory capabilities along the corridor spine.

$22B+Murray-Darling agricultural GDP protected
2.5%Gross revenue royalty to Indigenous SWF
8–12%Target inflation-hedged returns for superannuation
Asia-PacificEnergy and compute bridge

11. The Gorge Pairs — Seven Sites

Seven gorge pairs in the MacDonnell Ranges (both West and East MacDonnell) provide the upper reservoir storage. Each pair consists of a natural gorge pound dammed at the outlet as the upper reservoir, and a constructed lower reservoir at the base of the gorge. The 770 m head differential between upper and lower water levels drives the turbine-generators.

Specific gorge names are withheld from public documents as defensive prior art protection. The ANU STORES atlas (2018) identified 1,547 potential pumped hydro sites in the Northern Territory, with many sites in the Alice Springs region offering 200–500 m+ heads. The MacDonnell Ranges consistently offer the highest available heads in central Australia — steep quartzite walls requiring minimal dam height to impound significant volumes.

ParameterPer gorge pair (average)Total system (7 pairs)
Storage volume~2,286 GL16,000 GL
Upper reservoirNatural gorge pound — dammed outlet7 upper reservoirs
Lower reservoirConstructed — base of gorge7 lower reservoirs; concrete-faced rockfill
Generation capacity~5.7 GW40 GW
Head~770 m avg~770 m system average
Turbine typeFrancis reversibleStandardised across all 40 GW

12. Key Engineering Considerations

IssueImpactResolution path
Gorge geology and seismicityCentral Australia has low but non-zero seismic risk; gorge wall stability under reservoir loadingGeotechnical investigation — bore logs, seismic survey per gorge site
Evaporation lossesCentral Australian pan evaporation 2–3 m/year — open reservoir loses 5–15% annuallyPrefer narrow deep gorges; floating covers on lower reservoirs; include in water budget
Aboriginal cultural heritageMacDonnell gorges hold deep Arrernte cultural significance — most within Tjoritja National ParkCo-design process with Traditional Owners — essential precondition for any development
Reversible pump-turbine procurement40 GW of reversible pump-turbines is 11× the world’s largest existing installationInternational procurement staged across 4 phases — each phase uses proven technology
Conduit friction losses243 m friction head adds 33% to pump power over 2,000 kmDetailed hydraulic model — booster station spacing, pressure management
Environmental flowsSouthern water delivery must consider ecological requirements of inland riversEnvironmental flow assessment — Lake Eyre basin, Murray-Darling connections
Net water delivery volumeActual annual delivery depends on pumping hours, evaporation, agricultural demandFull water balance model — inflow, storage, evaporation, demand, export

13. The Physics Are Fixed

Australia possesses the sun, the gorges, the corridors, and the savings pool. These are not policy choices — they are geography. The MacDonnell Ranges were carved by geology over hundreds of millions of years into exactly the shape required for high-head pumped hydro storage. The central Australian solar resource is the most abundant on earth. The water that floods northern Australia every wet season and runs to the sea is available for capture without affecting base flows or ecological function.

Alice Hub + MMC turns these fixed physical facts into a continental endowment that solves energy, water, and economic security simultaneously — in the same timeframe and with comparable capital as today’s disconnected programme of batteries, gas peakers, and desalination plants that each solve one problem at high cost.

Recommendation: Proceed with Phase 1 detailed feasibility and secure initial superannuation and AI pre-commitments immediately. Phase 1 alone — 2.5 GW of firm dispatchable power at $4–8B — is a standalone investment case. The rest of the programme follows from Phase 1’s proof of concept.