Contents
1. Setting up the room
- Client: Java 17 or later and JavaFX 21 (
mvn clean javafx:run, or a packaged version). - Calculation server: hosted remotely (VPS); nothing to install on the computers. Enter on each computer (or give to the students) the institution's access key: Simulation › Calculation and server settings, « Encrypted connection » ticked. One key per institution, valid for the academic year; report to the supplier any key circulated outside the institution (it will be revoked and replaced). Before the session, check that the room has Internet access and that the institution's firewall lets the server port through (Test the connection from one computer: it must show « valid key »). A whole class calculating at the same time is not a problem: each calculation weighs a few kilobytes and takes less than one second (a few seconds for the DER studies of level 5, up to about fifteen seconds for the test bench of level 7).
- Unstable connection: schedule the network sessions (levels 1, 2, 5, 6 and 7) at times when the connection is reliable; the photovoltaic, wind and economics sessions (levels 3 and 4) work offline. The reference results of the tutorial allow marking even without the server.
- Examples: when the tutorial is first opened, they are copied to
~/.nrjxpert/aide/tutoriel/exemples/; a student who modifies them keeps his or her version. - Weather data: downloading them also requires the Internet; prepare the CSV files in advance for an offline session.
- Language: with the interface in English (Options › Language), the Help menu opens the English pages of the tutorial.
2. Progressions
| Programme | Volume | Content | Assessment |
|---|---|---|---|
| Higher technician diploma in electrical engineering, professional bachelor in renewable energy | 40 h (12 h lectures, 28 h labs) | Level 1; level 3 § 3.1 to 3.4; level 4 § 4.1 to 4.3; case study 1 (decentralised part) | 2 marked labs + 1 sizing report |
| Bachelor in electrical engineering (3rd year) | 60 h | Levels 1 and 2; level 3 complete; level 4 | Written exam + marked labs |
| Engineering school / master (1st year) | 60 h | Level 2 in depth (load flow, short circuit); levels 3 and 4; case studies 1 to 3 | Project in pairs + exam |
| Master in renewable energy / power networks (2nd year) | 40 h | Level 5; case studies 2 and 4; projects A to C of level 5 | Project + presentation |
| Smart grid specialisation (2nd-year master, specialised master, utility engineers) | 30 h + project | Level 6 complete: SGAM, FLISR and reliability, IVVC/r, VPP, microgrids, EV, CIM and IEC 61850, owner's engineering; synthesis project | Owner's engineering mission report + presentation |
| Smart grid expert (after the specialisation) | 24 to 30 h + assignment | Level 7: IEEE 2030.8 tests, smart metering and non-technical losses, DLMS/COSEM data collection, OpenADR 2.0b demand response, IEC 62443 cybersecurity; expert assignment § 7.6 | Test report + loss audit + risk assessment, presentation |
| Continuing education for smart grid consultants / project managers | 3 days | Level 6 § 6.1, 6.2, 6.8, 6.9, 6.10; labs 6.3 and 6.9; use case sheets on a real project | Use case sheet + bid analysis grid |
| Continuing education (consulting firms, installers) | 3 to 5 days | Level 3, wiring, level 4, case study adapted to the trade | Real case study |
3. Lab sessions
| Session | Duration | Content (references to the tutorial) | Deliverable |
|---|---|---|---|
| 1. Getting started | 2 h | Lab 1 (load and RL line), examples 1.1 and 1.2 drawn | Table hand calculation / software |
| 2. Three-phase and compensation | 3 h | Lab 2, example 1.4, exercise 3 of level 1 | Report |
| 3. Transformer and voltage drop | 3 h | Examples 2.1 and 2.2; three-phase transformer of the palette | Report |
| 4. Load flow | 4 h | Example 2.3 by hand, lab 3, exercise 3 of level 2 | Comparison of the 3 methods, voltage profile |
| 5. Short circuit | 4 h | Example 2.4, lab 4, exercise 1 of level 2, case study 3 | Choice of the protections |
| 6. Solar resource and weather | 2 h | Lab 5, example 3.1 | Site sheet |
| 7. Stand-alone PV system | 4 h | Example 3.3, lab 6, exercise 1 of level 3 | Sizing report |
| 8. Wiring and costs | 3 h | Example 3.4, lab 7, exercise 2 of level 3 | Table of links, quotation |
| 9. Wind | 3 h | Examples 3.6 and 3.7, lab 8, case study 4 | Production note |
| 10. Solar water pumping | 2 h | Example 3.8, lab 8 bis, exercise 4 of level 3, case study 5 | Pump and array sizing note |
| 11. Economics and viability | 4 h | Examples 4.1 to 4.4, lab 9, case study 2 | NPV, IRR, LCOE, sensitivity |
For level 5, plan 3 sessions of 4 h (lab 10 and projects A to C).
For level 6, plan 5 sessions of 4 h: (1) SGAM and protocols (tools 6.1 and 6.8, lab 6.1); (2) FLISR and reliability (example 6.3, lab 6.3, reliability calculator); (3) IVVC/r and CVR (example 6.4); (4) VPP, EV and microgrids (examples 6.5 and 6.6, lab 6.7); (5) owner's engineering: IEC 62559 sheet, specification, TCO, acceptance plan (lab 6.9). The interactive tools (SGAM mapping, use case sheet, self-assessment) keep the entries in the student's browser: have the work exported (Markdown or text) to hand it in.
For level 7, plan 4 sessions of 4 h and the assignment: (1) microgrid test bench (example 7.1, lab 7.1); (2) smart metering and losses (examples 7.2, labs 7.2); (3) OpenADR demand response (example 7.3, lab 7.3); (4) IEC 62443 risk assessment (lab 7.4). The HTML reports produced by NRJXpert (Report… button) are the deliverables.
Marking scheme of the level 6 synthesis project (out of 20)
| Criterion | Points |
|---|---|
| Diagnosis and NRJXpert model of the feeder (load flow, hosting capacity) | 3 |
| IEC 62559 use case sheets and SGAM mapping | 4 |
| Studies: reliability (2, 4, 6 switches), IVVC, VPP, islanding — interpretation of the results | 5 |
| Specification: interoperability (CIM, IEC 61850, points list), cybersecurity | 3 |
| Bid analysis (TCO, grid) and FAT/SAT acceptance plan | 3 |
| Quality of the report and of the presentation | 2 |
4. Assessment and marking schemes
Lab report (out of 20)
| Criterion | Points |
|---|---|
| Data and assumptions clearly stated (units, sources) | 3 |
| Detailed hand calculation of at least one result | 5 |
| Software results correctly recorded (screenshots, tables) | 4 |
| Comparison and explanation of the differences | 4 |
| Physical interpretation, answers to the « what happens if… » questions | 3 |
| Presentation | 1 |
Sizing report (out of 20)
| Criterion | Points |
|---|---|
| Realistic and justified load assessment | 3 |
| Sizing of the generator, storage and electronics (method and rounding) | 5 |
| Wiring: cross-sections, protection, voltage drops, costs | 4 |
| Economic study (discounted cost, LCOE, comparison of variants) | 4 |
| Sensitivity and reasoned recommendation | 3 |
| Design note following the template (case studies) | 1 |
The end-of-level quizzes (8 to 12 questions) lend themselves to formative assessment: the student does them alone, the score is displayed; they can be reused for summative assessment on paper.
↑ Back to top5. Exam subjects (2 h, documents allowed: formula sheet of the appendices)
Subject A — Electrification of a health post (technician)
- Draw up the energy balance of a health post (list of appliances provided).
- Size the array, battery, charge controller and inverter at 24 V for a worst month of 4.8 kWh/m²/d.
- Choose the cross-section of the array → controller cable (12 m, ΔU ≤ 3 %) and its protection.
- Calculate the annuity and the cost of the kWh over 15 years at 8 %.
Solution: follow example 3.3 and example 3.4; marks 5 + 7 + 4 + 4.
Subject B — Distribution network (engineer)
- Three-node network (data of lab 3): write Ybus in pu (base 10 MVA, 30 kV); do one Gauss-Seidel iteration.
- Comment on the NRJXpert results provided (Newton-Raphson): losses, reactive power of the PV node.
- Three-phase and phase-to-earth short circuit at node 3 (data provided), choice of the breaking capacity.
- A 2 MW PV plant is added at node 3: expected effects on the voltage and the losses; control law to propose.
Solution: examples 2.3, 2.4; lab 3; § 5.2. Marks 6 + 4 + 6 + 4.
Subject C — Hybrid project (master)
Compare for a 100 kW peak site: genset alone, PV + batteries, optimised hybrid (level 5 results provided). Discuss the discount rate, the price of diesel and the renewable share; conclude with a quantified recommendation.
6. Final-year projects
- Electrification plan of a municipality: centralised, decentralised, grid extension (case studies 1 and 2, level 5).
- PV hosting capacity of a real MV feeder (operator's data) and connection rules.
- Stability of an island microgrid (Saloum islands) with grid-forming batteries.
- Update of the equipment database with market prices and sensitivity study of the LCOE.
- Measurement / simulation comparison on an existing PV installation of the school.
- Loss audit of a real feeder with smart-meter data (level 7) and AMI business case.
7. Teaching tips
- Require the hand calculation before using the software; mark the explanation of the differences more than the value obtained.
- Vary one input at a time and ask for a qualitative prediction before running the calculation again.
- Use local data (site weather, supplier prices, measured consumption profiles): motivation and the quality of the discussions improve markedly.
- Recall the limits of the models: transformer ratio not represented by the server, indicative prices, typical days.
- Unit entry errors (mH/H, kV/V, kW/W) are the first cause of absurd results: have the orders of magnitude checked.
Author
November 2026