Answer a few plain questions about your home or project. You get a complete report: what to buy, which parts are compulsory in Nepal, how every wire connects, step-by-step installation, tests, and the cost.
Choose the one that fits. Both ask only what you can answer and explain how to find each number.
Grid-tied, hybrid with battery backup for load-shedding, or fully off-grid.
Feasibility and construction package for 100 kW to 50 MW plants.
Every part in plain language: panels, inverters, MPPT vs PWM, batteries, cables, MC4, protection, earthing, monitoring - with Nepal prices and what is compulsory.
Three minutes of questions, then a report you can follow.
Nearest city (or exact map point), roof type, and what you want: lower bill, backup, or off-grid.
Units from your NEA bill, or pick your appliances. Hints under every box say how to measure it.
Sizes, drawings, shopping list, cable sizes, installation steps, tests and money - on screen and as a PDF.
Check equipment against the NEPQA list, wire it as drawn, run the tests, and apply to NEA before connecting.
Real outputs of this app with real PVGIS data - the same thing you get for your own project.
A family with no grid connection wants lights, a TV, phone charging, a laptop and Wi-Fi, and power for 2 days without sun. Jumla is cold (record low about −15 °C), so the battery lives indoors.
Total about 860 Wh a day (≈ 26 units a month).
| Item | Compulsory or optional? | Specification | Qty |
|---|---|---|---|
| Solar PV module | Compulsory (safety) | 550 Wp mono/TOPCon, Voc 49.5 V, Vmp 41.6 V, Isc 14 A, efficiency ≥ 21 %, power warranty ≥ 80 % at 25 yr, IEC 61215/61730 | 1 |
| Mounting structure | Compulsory (safety) | Hot-dip galvanised / aluminium tilt frame with anchor bolts, tilt as designed | 1 row(s) of up to 1 |
| Mounting rails | Compulsory (safety) | Aluminium PV rail (2 per row of panels) | 3 m |
| End clamps / mid clamps | Compulsory (safety) | Matching panel frame thickness | 4 end / 0 mid |
| Roof feet / anchors | Compulsory (safety) | Stainless fixings, sealed against leaks | 4 |
| PV cable (red and black) | Compulsory (safety) | 10 mm² solar cable EN 50618 (H1Z2Z2-K), UV resistant, 1500 V DC | 13 m red + same black |
| MC4 connector pairs | Compulsory (law / NEA) | Same brand as panel connectors (never mix brands) | 4 |
| DC isolator (PV) | Compulsory (safety) | 150 V DC, ≥ 25 A, 2-pole, lockable | 1 |
| DC surge protection device (Type 2, PV) | Strongly recommended | Ucpv ≥ 150 V DC, In ≥ 20 kA | 1 |
| MPPT charge controller | Compulsory (safety) | 30 A, 24 V battery, PV max 150 V, efficiency ≥ 95 %, battery-type setting for LiFePO4 (lithium) | 1 |
| Off-grid inverter | Compulsory (safety) | 0.5 kW continuous, surge ≥ 0.2 kW, 24 V DC input, pure sine 230 V 50 Hz | 1 |
| Battery | Compulsory (safety) | LiFePO4 24 V 100 Ah with BMS, ≥ 3000 cycles @ 80 % DoD, round-trip ≥ 85 %, warranty ≥ 5 yr, communication with inverter (CAN/RS485) | 1 |
| Battery cable (red and black) | Compulsory (safety) | 10 mm² flexible copper, crimped lugs | 4 m each colour |
| Battery fuse (DC, high breaking capacity) | Compulsory (safety) | 32 A NH/ANL/class-T DC fuse | 1 |
| Battery isolator / DC breaker | Compulsory (safety) | 32 A, 24 V DC rated | 1 |
| AC MCB (inverter output) | Compulsory (safety) | 6 A, C-curve, 1-pole + N | 1 |
| RCD / RCBO | Compulsory (safety) | 30 mA, Type A (Type B if the inverter manual requires) | 1 |
| AC surge protection device (Type 2) | Strongly recommended | 275 V AC, In ≥ 20 kA | 1 |
| AC cable | Compulsory (safety) | 2.5 mm² copper (phase + neutral) + 2.5 mm² earth | 7 m |
| Earth electrode | Compulsory (safety) | Copper-bonded rod ≥ 1.5 m (or copper plate earth pit per local practice), inspection pit | 1 |
| Earth cable (green/yellow) | Compulsory (safety) | 6 mm² frame bonding, 16 mm² to electrode, 2.5 mm² PE | 17 m total |
| Conduit / cable tray, glands, ties | Compulsory (safety) | UV-resistant conduit outdoors; glands sized to cables | as required |
| Warning labels | Compulsory (safety) | 'Solar DC - live in daylight', isolator labels, dual-supply label at DB and meter | 1 |
| Circuit | From → To | Length (m) | Design current (A) | Protective device (A) | Chosen (mm²) | Voltage drop (%) |
|---|---|---|---|---|---|---|
| PV string cable (each string, + and −) | Array → MPPT charge controller | 10.0 | 17.5 | 17.5 | 10 | 1.39 |
| Battery cable (+ and −) | Battery bank → fuse/isolator → inverter | 1.5 | 22.9 | 32 | 10 | 0.63 |
| Controller → battery | Charge controller → battery busbar | 1.5 | 24.0 | 30 | 10 | 0.66 |
| Inverter AC output | Inverter → distribution board | 5.0 | 2.2 | 6 | 2.5 | 0.08 |
| PV frame bonding (earth) | Each panel frame / rail → earth bar | - | - | - | 6 | - |
| Main earthing conductor | Main earth bar → earth electrode | 10.0 | - | - | 16 | - |
| Inverter / DB protective earth (PE) | Inverter → DB earth bar | 5.0 | - | - | 2.5 | - |
⬇ Full off-grid report (PDF) - parts explained, installation steps, tests
| Item | Quantity | Unit | Rate (central, NPR) | Low (NPR lakh) | Central (NPR lakh) | High (NPR lakh) |
|---|---|---|---|---|---|---|
| PV modules (550 W TOPCon, bulk import, landed incl. VAT) [A] global price 11.4-16 US¢/W (Ekantipur, May 2026) × NPR 140/USD + ~15 % freight/clearing + 13 % VAT | 501,600 | Wp | 25 | 105.3 | 125.4 | 150.5 |
| String inverters (100 kVA class, NEPQA certified) [A] international utility string-inverter prices ~US$40-70/kW + import | 400 | kVA | 7,500 | 22.0 | 30.0 | 40.0 |
| Mounting structure, hot-dip galvanised, incl. foundations [S] Indian benchmark ₹6,000-12,000/kW (Bridgeway Power) × 1.6 | 502 | kWp | 12,800 | 48.2 | 64.2 | 96.3 |
| PV string cable 4 mm² H1Z2Z2-K [A] Indian ₹55-100/m × 1.6 | 5,800 | m | 120 | 5.2 | 7.0 | 9.3 |
| MC4 connector pairs (genuine, module maker's type) [A] | 96 | pair | 300 | 0.1 | 0.3 | 0.4 |
| DC surge protectors Type 2 [A] | 40 | unit | 5,000 | 1.2 | 2.0 | 3.2 |
| LV AC cable (single-core length) [A] Indian 70 mm² Cu ₹600-800/m × 1.6 | 2,400 | m | 1,200 | 21.6 | 28.8 | 38.4 |
| AC combiner board with breakers (per inverter) [A] | 4 | inverter | 50,000 | 1.2 | 2.0 | 3.2 |
| Step-up transformer 0.8/11 kV ONAN [A] Indian distribution transformer ≈ ₹1,800/kVA × 1.6 + transport | 500 | kVA | 3,500 | 12.5 | 17.5 | 25.0 |
| 11 kV switchgear (RMU / VCB panels) + protection relays [A] Indian ₹5-10 lakh per panel × 1.6 | 3 | panel | 1,200,000 | 24.0 | 36.0 | 48.0 |
| 11 kV XLPE cable (single-core length) [A] Indian ₹800-1,500/m × 1.6 | 1,500 | m | 1,800 | 19.5 | 27.0 | 36.0 |
| 11 kV overhead line to the NEA substation [A] no NEA unit rate found - get the NEA connection estimate | 2 | km | 2,500,000 | 36.0 | 50.0 | 70.0 |
| NEA revenue metering, SCADA, weather station, CCTV [A] | 1 | lot | 2,500,000 | 15.0 | 25.0 | 40.0 |
| Perimeter fence 2.1 m with gates [A] | 276 | m | 3,500 | 6.9 | 9.7 | 13.8 |
| Site levelling, drainage, internal roads, control room [A] | 502 | kWp | 3,000 | 10.0 | 15.0 | 25.1 |
| Earth mesh, electrodes, lightning protection [A] | 502 | kWp | 1,200 | 4.0 | 6.0 | 10.0 |
| Installation, testing and commissioning labour [A] | 502 | kWp | 4,000 | 15.0 | 20.1 | 30.1 |
| Engineering, permits (DoED, IEE), PPA, insurance [A] 3 / 4 / 6 % | % of hard cost | 4% | 10.4 | 18.6 | 38.4 | |
| Contingency [A] 5 / 7.5 / 10 % | % | 7.5% | 17.9 | 36.3 | 67.8 | |
| Total (incl. engineering/permits and contingency) | 376.2 | 520.9 | 745.4 |
[S] = secondary source, [A] = assumption where no Nepali price was found - replace with quotes. Land, financing and VAT recovery not included. Land needed about 0.47 ha (Nepal projects often use ~2 ha/MW with roads and setbacks).
⬇ Full 500 kW report (PDF) - BOQ, cable schedule, construction steps, tests
| Item | Quantity | Unit | Rate (central, NPR) | Low (NPR lakh) | Central (NPR lakh) | High (NPR lakh) |
|---|---|---|---|---|---|---|
| PV modules (550 W TOPCon, bulk import, landed incl. VAT) [A] global price 11.4-16 US¢/W (Ekantipur, May 2026) × NPR 140/USD + ~15 % freight/clearing + 13 % VAT | 1,003,200 | Wp | 25 | 210.7 | 250.8 | 301.0 |
| String inverters (100 kVA class, NEPQA certified) [A] international utility string-inverter prices ~US$40-70/kW + import | 700 | kVA | 7,500 | 38.5 | 52.5 | 70.0 |
| Mounting structure, hot-dip galvanised, incl. foundations [S] Indian benchmark ₹6,000-12,000/kW (Bridgeway Power) × 1.6 | 1,003 | kWp | 12,800 | 96.3 | 128.4 | 192.6 |
| PV string cable 4 mm² H1Z2Z2-K [A] Indian ₹55-100/m × 1.6 | 11,500 | m | 120 | 10.3 | 13.8 | 18.4 |
| MC4 connector pairs (genuine, module maker's type) [A] | 192 | pair | 300 | 0.3 | 0.6 | 0.9 |
| DC surge protectors Type 2 [A] | 70 | unit | 5,000 | 2.1 | 3.5 | 5.6 |
| LV AC cable (single-core length) [A] Indian 70 mm² Cu ₹600-800/m × 1.6 | 4,200 | m | 1,200 | 37.8 | 50.4 | 67.2 |
| AC combiner board with breakers (per inverter) [A] | 7 | inverter | 50,000 | 2.1 | 3.5 | 5.6 |
| Step-up transformer 0.8/11 kV ONAN [A] Indian distribution transformer ≈ ₹1,800/kVA × 1.6 + transport | 800 | kVA | 3,500 | 20.0 | 28.0 | 40.0 |
| 11 kV switchgear (RMU / VCB panels) + protection relays [A] Indian ₹5-10 lakh per panel × 1.6 | 3 | panel | 1,200,000 | 24.0 | 36.0 | 48.0 |
| 11 kV XLPE cable (single-core length) [A] Indian ₹800-1,500/m × 1.6 | 1,500 | m | 1,800 | 19.5 | 27.0 | 36.0 |
| 11 kV overhead line to the NEA substation [A] no NEA unit rate found - get the NEA connection estimate | 2 | km | 2,500,000 | 36.0 | 50.0 | 70.0 |
| NEA revenue metering, SCADA, weather station, CCTV [A] | 1 | lot | 2,500,000 | 15.0 | 25.0 | 40.0 |
| Perimeter fence 2.1 m with gates [A] | 390 | m | 3,500 | 9.8 | 13.7 | 19.5 |
| Site levelling, drainage, internal roads, control room [A] | 1,003 | kWp | 3,000 | 20.1 | 30.1 | 50.2 |
| Earth mesh, electrodes, lightning protection [A] | 1,003 | kWp | 1,200 | 8.0 | 12.0 | 20.1 |
| Installation, testing and commissioning labour [A] | 1,003 | kWp | 4,000 | 30.1 | 40.1 | 60.2 |
| Engineering, permits (DoED, IEE), PPA, insurance [A] 3 / 4 / 6 % | % of hard cost | 4% | 17.4 | 30.6 | 62.7 | |
| Contingency [A] 5 / 7.5 / 10 % | % | 7.5% | 29.9 | 59.7 | 110.8 | |
| Total (incl. engineering/permits and contingency) | 627.9 | 855.7 | 1,218.7 |
[S] = secondary source, [A] = assumption where no Nepali price was found - replace with quotes. Land, financing and VAT recovery not included. Land needed about 0.95 ha (Nepal projects often use ~2 ha/MW with roads and setbacks).
⬇ Full 1 MW report (PDF) - BOQ, cable schedule, construction steps, tests
Download and see exactly what you will get.
Every number comes from a formula you can read in the report (Boxwell's Solar Electricity Handbook, Neill et al.'s Solar Farms, IEC standards) - never from AI guesses.
Prices and rules carry their source and date. Assumptions are labelled. Data that could not be verified is said to be unverified.
The report tells you what NEA must approve, what is compulsory for safety, and when to get help with 230 V wiring.