01
Fast route
Professional Check
Five warranty and ageing decisions, one retention calculation and a hostile test of an augmentation assumption.
- Five focused lessons
- 10 scored questions
- Answer rationales after submission
About 15 minutes
Vitreous Learning 05
Professional BESS course · Great Britain
A warranty is a testable boundary, not a health forecast
Separate ageing physics, operating duty, guaranteed metrics and commercial remedies. Then test whether an augmentation plan restores the promised capability.
2 learning routes80% pass standard30 assessment questions
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Evidence ledIECIEEESandiaTechnical cut-off · 24 August 2026
One subject · two depths
Choose your route
This course focuses on the gap between a degradation curve in a model and the enforceable performance of an operating BESS.
02
Full route · recommended
Detailed Course
From calendar and cycle ageing through warranty matrices, measurement, remedies, augmentation and a complete lifecycle case.
- Nine detailed modules
- Moorland worked case
- 20 scored questions
75 to 90 minutes
Scores and progress remain on this device. No account or sign-up is required.
Professional Check · About 15 minutes
Can you tell a modelled fade curve from an enforceable guarantee?
Link operating conditions, test method, exclusions and remedy before relying on a warranty headline.
Lesson 1 of 5
Identify the ageing drivers
Calendar time, cycling, temperature, state of charge and power profile interact to change energy and resistance.
Calendar ageing continues while the asset waits. Cycle ageing depends on throughput, depth of discharge, C-rate and operating conditions. Thermal exposure and long periods at high state of charge can be material.
A single annual fade percentage compresses these drivers into an assumption. It should be treated as a scenario tied to a duty cycle.
Hostile check
A warranty-compliant dispatch profile can still age differently from the base-case model when temperature and dwell time change.
Lesson 2 of 5
Read the metric before the percentage
Capacity retention, available energy, round-trip efficiency, power and availability each need their own test boundary.
Eighty percent capacity retention can refer to cell DC capacity, installed DC capacity or net AC deliverable energy. State the start point, reference value, test power, temperature, state-of-charge endpoints and auxiliary treatment.
Warranty schedules may provide different limits by year, throughput or operating regime.
Hostile check
The same percentage can describe materially different commercial outcomes when boundaries differ.
Lesson 3 of 5
Link the guarantee to use
A warranty matrix usually limits throughput, cycles, energy windows and environmental conditions.
Compare the optimiser's intended duty against every operating limit. Excess throughput can reduce coverage or move the asset to another guarantee curve.
Track charge and discharge energy on the contractually defined side of the meter. A model using a different boundary can consume the allowance incorrectly.
Hostile check
A high-revenue dispatch is not valuable if it creates an unpriced loss of warranty coverage.
Lesson 4 of 5
Test the remedy
A measured shortfall creates value only if the contract supplies an enforceable remedy after exclusions and tolerance.
Read notice periods, test repetition, degradation tolerance, cure rights, liquidated damages, replacement obligations, caps and exclusions. Determine who pays for testing and lost availability.
Credit quality and parent support can matter as much as the mathematical guarantee.
Hostile check
A strong performance curve with a low liability cap can provide limited economic protection.
Lesson 5 of 5
Price augmentation honestly
Augmentation restores capability by adding equipment, with integration, downtime, safety and warranty consequences.
Model equipment, transport, installation, controls, commissioning, permits, outage, disposal and tax treatment. State the trigger and who carries price and availability risk.
Compare augmentation with initial oversizing and a lower-duty strategy using the same net-present-value boundary.
Hostile check
Assuming future modules at today's price and specification is a procurement forecast, not an engineering fact.
Professional Check assessment
Answer every question before submitting. Correct answers and rationales appear only after the complete attempt.
Professional CheckQuestion 1 of 10
Detailed Course · 75 to 90 minutes
Turn lifecycle assumptions into an auditable obligation
Build the chain from duty cycle and ageing to guaranteed performance, testing and augmentation economics.
Module 1 of 9
Separate calendar and cycle ageing
Lifecycle analysis needs two interacting clocks: elapsed time and electrochemical work.
Calendar ageing depends on time, temperature and state-of-charge exposure. Cycle ageing depends on energy throughput, depth, C-rate and the detailed duty cycle. Resistance growth can reduce deliverable power before energy reaches its limit.
Use a model calibrated for the chemistry and operating regime. Carry uncertainty rather than one false-precision curve.
Hostile check
A test based on full cycles may misrepresent a response asset dominated by shallow, high-frequency movements.
Module 2 of 9
Translate dispatch into warranty usage
Convert the dispatch trace into the exact counters used by the warranty.
Aggregate throughput, equivalent full cycles, time at high state of charge, temperature exceedances and power events. Reconcile BMS records with the contractual measurement boundary.
Define how partial cycles, energy used for auxiliaries and outages are treated. Preserve data quality and missing intervals.
Hostile check
Equivalent full cycles alone can hide a damaging duty profile with the same total throughput.
Module 3 of 9
Read the guarantee matrix
Guarantees can be indexed by year, throughput, temperature and operating envelope.
Identify whether the guaranteed metric is an absolute value or percentage of an acceptance-test baseline. Check linear interpolation, tolerances and which curve applies if more than one usage limit is reached.
Keep energy, power, efficiency and availability guarantees separate, with their respective remedies.
Hostile check
Choosing the most favourable curve after the fact can breach the contract's usage-selection logic.
Module 4 of 9
Design a repeatable performance test
A warranty claim depends on a controlled, contract-compliant test and calibrated data.
Define preconditioning, temperature, rest, power, endpoints, measurement accuracy and auxiliary treatment. Record unavailable blocks and any derates. Use the same baseline methodology as commissioning.
Plan test energy, market outage and safety controls. A failed first test may trigger repeat or cure procedures.
Hostile check
An operational discharge event is weak warranty evidence when it does not meet the contractual test protocol.
Module 5 of 9
Separate availability from capacity
Availability measures readiness over time. Capacity measures capability under test conditions.
Exclude or include planned maintenance as the contract specifies. Apply force-majeure and grid-outage rules consistently. For capacity, test the available equipment and state any block exclusions.
Model revenue using both metrics. A healthy but unavailable asset cannot earn, and an available degraded asset can lack duration.
Hostile check
Multiplying two percentages can help a revenue model, but it does not create a new warranty metric.
Module 6 of 9
Audit exclusions and liability
Commercial protection is determined by remedies, caps, security and dispute process.
Review exclusions for dispatch outside envelope, grid conditions, ambient temperature, cyber events, third-party controls and maintenance failures. Test whether causation must be proven.
Map each breach to cure, replacement, liquidated damages or termination. Compare exposure with liability caps and credit support.
Hostile check
A guaranteed number without a workable claim process can be difficult to monetise.
Module 7 of 9
Engineer the augmentation interface
New and aged blocks must coexist across electrical, controls, thermal and warranty boundaries.
Check voltage windows, state-of-charge balancing, BMS hierarchy, fire-safety evidence, spares and firmware compatibility. Define acceptance tests for the augmented system.
Allocate responsibility between original supplier, augmentation supplier, EPC, O&M provider and optimiser.
Hostile check
Adding MWh can reduce system availability if controls and warranty interfaces are unresolved.
Module 8 of 9
Model lifecycle economics
Compare revenue preserved with augmentation cost, outage, degradation and residual value.
Use scenario-specific dispatch and price curves. Discount cashflows at the project boundary and include tax, financing and replacement timing consistently.
Stress module price, delivery delay, retained energy, revenue saturation and warranty recovery. Avoid treating vendor damages as guaranteed cash.
Hostile check
A base case that requires warranty damages to achieve target return is structurally fragile.
Module 9 of 9
Moorland worked warranty audit
The case connects usage, test result, tolerance and augmentation decision.
Moorland begins at 100 MWh AC tested energy. The year-five guarantee is 82 MWh after no more than 1,500 equivalent full cycles. The asset records 1,420 cycles and tests at 79.5 MWh. The contract allows a 1 MWh measurement tolerance, so the warranty shortfall is 1.5 MWh.
The remedy is replacement capacity capped at £140,000/MWh of shortfall. Maximum nominal remedy is £210,000, subject to exclusions. A planned 8 MWh augmentation costing £1.1 million serves a wider duration objective and should not be confused with the warranty cure.
Guaranteed82 MWh
Tolerance-adjusted80.5 MWh
Shortfall1.5 MWh
Hostile check
Subtracting the full 8 MWh augmentation cost from the supplier is unsupported. The measured warranty shortfall and contractual cap define the claim.
Detailed Course assessment
Answer every question before submitting. Correct answers and rationales appear only after the complete attempt.
Detailed CourseQuestion 1 of 20