Putting a solar model and a battery model in the same workbook does not create a hybrid model. The combined asset is governed by the interfaces both components share and compete for: connection capacity, charging rights, controls, metering, contracts and performance responsibility.
At a glance
- A hybrid project is a third asset class, not two standalone projects sharing a site.
- Independent revenue curves overstate value when solar and BESS compete for the same POI, state of charge or dispatch opportunity.
- Shared infrastructure can reduce cost but may create a single point of failure and blurred performance responsibility.
- Mine-site solar, BESS and engines must be designed, controlled, tested and contracted as one reliable power system.
Revenue conflict hides inside the shared connection
Hybrid asset interface map
SolarGeneration and curtailment
BESSSOC, charging and services
Engines / gridFirming and backup
Common controllerPriority, dispatch and protection
Shared POIImport/export capacity
ContractsGuarantees and remedies
The combined asset is governed by shared interfaces. Separate component models cannot show these conflicts.
Solar wants to export during high irradiation. The battery may want the same connection capacity for an upward service or later discharge. If both share a limited POI, the model must decide which asset has priority, which output is curtailed and who bears the lost revenue.
The battery is also a load while charging. An existing generation connection may not automatically provide unrestricted import capacity. Connection agreements, GPS, metering and dispatch arrangements must be checked rather than assuming that export approval creates two-way freedom.
Simultaneous output → POI congestion → controller limitation → reduced deliverable service → lost revenue or performance breach.
Shared savings need an asset-by-asset proof
AFRY cites potential hybrid savings in the order of 5–15% CAPEX and 10–20% OPEX, mainly from shared connection, substation, civil works and asset management. These are external experience ranges, not project assumptions. The battery, warranty, insurance, spares and market costs do not disappear because solar is nearby.
Diligence should identify which equipment can actually be shared, whether capacity is adequate, whether consent can be modified, who guarantees availability and whether either asset can operate independently during an outage. Any saving should be net of additional control, testing and contract complexity.
The largest risk often sits between contracts
When the battery supplier covers DC blocks and PCS while the EPC or balance-of-plant contractor covers transformers, PPC, SCADA and the POI, assumptions can diverge. A disagreement over equipment quantity, control mode or transformer configuration can become a variation, performance gap or schedule claim.
An integrated interface matrix should map each function to design, supply, integration, testing, performance guarantee and remedy responsibility. The financial model must also use joint dispatch at an appropriate interval, including connection constraints, SOC, losses, degradation, curtailment absorption and service conflict.
For mining hybrids, reliability is a constraint
Solar + BESS + diesel or gas adds black start, spinning reserve, step-load and extreme-weather requirements. The lowest-LCOE combination is not necessarily capable of maintaining production. Reliability should be a binding design constraint, not a value added after optimisation.
The real diligence question is whether the combined assets can perform as one power station under a common control system. If the answer is not integrated into design, testing and contracts, the project is co-located equipment rather than a financeable energy system.
Pre-DD implication: F2 checks the shared physical site and infrastructure. F3 defines POI, charging, dispatch, controls and reliability. F4 uses joint rather than additive cashflow and tests whether interface responsibility is contractually closed.
Basis
Written from public information and Heliovulcan’s own screening work. Where an external source informs the argument, it is named in the text rather than absorbed into it.
Status
Analytical note on project logic at screening grade. Not legal, financial, tax, engineering, investment or formal due-diligence advice, and not a financial product recommendation. Any figure should be independently verified before a commercial decision.
