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Портативная электростанция для дома 500Вт с солнечной панелью 200W и АКБ LiFePO4 12.8V 100Ah (1280W) инвертор 500Вт (макс 1000Вт) чистая синусоида + ШИМ 30А
200 Вт · 44 В · IP67
UAH 19,590In stock
Where to start: the list of loads
List everything that has to keep running during an outage, with its actual power draw — from the data sheet or the rating label on the case. For motors and compressors, account separately for the starting current: at start-up they draw 2–3 times their rated power for about a second.
| Load | Power, W | Start | Note |
|---|---|---|---|
| Router and optical terminal | 10–20 | — | Runs continuously |
| LED lighting for a flat | 40–80 | — | 5–8 luminaires of 8–10 W |
| Laptop | 45–90 | — | Charging plus use |
| Television | 60–150 | — | Depends on the screen size |
| Gas boiler with circulation pump | 80–150 | ×2 | Sensitive to the waveform and to phasing |
| Refrigerator | 100–200 | ×3 | The compressor runs in cycles |
| Desktop computer with monitor | 200–400 | — | Gaming machines draw more |
| Water supply pump | 500–1 000 | ×3 | The highest starting current |
| Microwave oven | 1 000–1 300 | — | Draws more than the figure on the door |
| Electric kettle, water heater, heater | 1 500–2 500 | — | Usually left off the backup: they drain the battery within an hour |
Inverter power
The inverter must carry the sum of the continuous loads with a margin and withstand the start of the largest motor.
Pinv = ΣP × 1.25, where ΣP is the total power of the loads switched on at the same time. The 25 % margin covers heating, inaccuracy in the data sheet figures and new appliances.
Ppeak = ΣP + Pmotor × (k − 1), where k is the starting factor of the most powerful motor. The inverter’s peak power (listed separately in the data sheet, usually twice the rated power for a few seconds) must be no lower than Ppeak.
Other requirements: a pure sine wave — for a boiler, a fridge, pumps and any equipment with a motor or a switch-mode power supply; a modified sine wave suits only lamps and chargers. For a boiler — correct output phasing (phase and neutral are not swapped) and a transfer time of no more than 10–20 ms if the inverter works in UPS mode.
Battery capacity: Wh and Ah
A battery is sized by energy, not by power. First, how many watt-hours have to be delivered; then, how many ampere-hours that means at the chosen voltage.
E = ΣP × t ÷ η ÷ DoD, where t is the hours of autonomy, η is the inverter efficiency (0.9), DoD is the working depth of discharge: 0.9 for LiFePO4, 0.5 for gel and AGM.
C = E ÷ U, where U is the system voltage: 12, 24 or 48 V. The result is in ampere-hours.
| Energy required, E | 12 V | 24 V | 48 V |
|---|---|---|---|
| 1 000 Wh | 83 Ah | 42 Ah | 21 Ah |
| 2 000 Wh | 167 Ah | 83 Ah | 42 Ah |
| 4 000 Wh | 333 Ah | 167 Ah | 83 Ah |
| 8 000 Wh | 667 Ah | 333 Ah | 167 Ah |
The system voltage follows the inverter power: up to 1–1.5 kW — 12 V, 2–3 kW — 24 V, from 3–5 kW — 48 V. The higher the voltage, the lower the current in the cables: 3 kW at 12 V means 250 A and cable from 70 mm², at 48 V — 63 A and 16 mm².
LiFePO4 or gel and AGM
| Parameter | LiFePO4 | Gel / AGM |
|---|---|---|
| Working depth of discharge | 80–90 % | 50 % |
| Service life | 3 000–6 000 cycles | 500–800 cycles |
| Weight per 1 kWh | 10–12 kg | 25–30 kg |
| Charging rate | 0.5–1C, 1–2 hours | 0.1–0.2C, 8–10 hours |
| Operation in frost | Discharge down to −20 °C, charging only above 0 °C (the BMS blocks it) | Works, but capacity drops by 30–50 % |
| Price per kWh | Higher up front | Lower up front |
| Price per cycle | 3–5 times lower | Higher |
Gel makes sense for occasional outages and small UPS units where the battery stays charged for years. For daily cycling choose LiFePO4: it delivers twice as much from the same rated capacity and lasts 5–8 times longer.
Charging and solar panels
The battery has to recharge between outages. The charging current of a hybrid inverter is usually 20–60 A; a 48 V 100 Ah battery charges from empty at 40 A in 2.5–3 hours, a gel battery of the same size takes 8–10 hours at a low current.
Solar panels reduce dependence on the outage schedule: 1 kW of panels yields 4–5 kWh a day in summer and 1–1.5 in winter. Panels need an MPPT controller or a hybrid inverter with a PV input; the voltage and current of the panel array are checked against the input range.
Example: a flat over 8 hours
Load: router 15 W + lighting 60 W + laptop 65 W + boiler with pump 120 W + fridge 150 W = 410 W.
Inverter: 410 × 1.25 = 513 W. Peak: 410 + 150 × (3 − 1) = 710 W. A 1 000 W pure sine wave inverter with a 2 000 W peak meets both conditions.
Energy for 8 hours: 410 × 8 ÷ 0.9 = 3 644 Wh (the fridge runs in cycles, so the real figure is lower — we calculate with a margin).
LiFePO4: 3 644 ÷ 0.9 = 4 050 Wh → 12 V: 337 Ah; 24 V: 169 Ah; 48 V: 84 Ah. The practical choice is 24 V 200 Ah or 48 V 100 Ah (5.1 kWh): both leave a reserve for a long evening.
Gel: 3 644 ÷ 0.5 = 7 288 Wh → 12 V: 607 Ah, that is, six 100 Ah batteries weighing about 180 kg. That is why lithium is used for daily autonomy.
Common mistakes
- An inverter sized for the average rather than the peak load — the fridge does not start, the inverter goes into protection.
- A modified sine wave on a boiler or a pump — hum, overheating, electronics failures.
- A gel battery run down “to zero” — it loses service life after a few dozen deep cycles.
- Thin cables at 12 V — heating, voltage drop, emergency shutdown under load.
- Parallel connection to the grid without an ATS (automatic transfer switch) or a changeover switch — dangerous for electricians working on the line, and prohibited.
