8 kW Solar System with 16 kWh Battery
For a large house or a small business with real daytime load: 8.25 kWp, 16.08 kWh of storage and an 8 kW hybrid that can carry two air conditioners plus a workshop.
- PV array
- 8.25 kWp
- 15 x 550 W
- Battery
- 16.08 kWh
- 14.47 kWh usable
- Inverter
- 8 kW
- 8 kW / 48 V hybrid inverter
- Daily output (South Africa)
- 34 kWh
- South Africa, 5.5 kWh/m2/day
Eight kilowatts is where a residential kit starts behaving like a small commercial system. The 8.25 kWp array is 15 modules, and the 8 kW hybrid has the surge capacity to start a 2.2 kW borehole pump while two inverter air conditioners are already running — a combination that trips a 5 kW unit on a hot afternoon.
The 16.08 kWh bank is sized to the array rather than to the house: it absorbs a full day of surplus (about 10-14 kWh in these markets after daytime loads) without clipping, so nothing is thrown away at midday and the evening has a full pack. That ratio — roughly 2 kWh of storage per kWp — is the one we default to for hybrid systems because it keeps the battery in daily cycling rather than sitting at 100% for weeks.
What's in the kit
The bill of materials below is what ships, not a wish list. Anything marked configurable is fixed at order confirmation against your grid, your generator and your load list.
| Item | Specification | Qty |
|---|---|---|
| PV modules | 550 W monocrystalline half-cell, 182 mm, 25-year performance warranty. Smaller DLXN-M10 50-230 W modules are available for outbuildings or a separate off-grid circuit. module range · DLXN-M10-230W | 15 x 550 W |
| Hybrid inverter Configurable | 8 kW / 48 V hybrid inverter, 2 x MPPT, 160 A charger. Configurable: 8 kW/48 V single-phase hybrid as standard; a 10 kW unit or a three-phase 8 kW model where the premises already has 380-400 V distribution. Generator input is on all variants. | 1 |
| Battery | DLXN-SL5314 — 16.08 kWh LiFePO4, 51.2 V / 314 Ah, 6,000-8,000 cycles, built-in BMS. Two DLXN-F5400 20.48 kWh packs take the bank to 40.96 kWh for a large house running two air conditioners at night; the SL5314 remains the cheaper starting point. DLXN-F5400 | 1 |
| Mounting | Mounting: 15 x rail sets across two roof planes, or a ground-mount frame if the roof area is split by dormers. Two orientations (east/west) are supported on separate MPPTs and typically flatten the midday peak by 15% while extending the useful window by two hours. | 1 |
| DC side / AC side | Balance of system: 2 x DC combiner with 40 A breakers and Type 2 SPD, 6 mm2 PV cable, 16-way AC board with RCD and surge arrestor, three CT clamps for per-phase export limiting, 4G monitoring with Modbus TCP for a BMS or EMS, and 2 m 95 mm2 battery leads with a 250 A DC breaker. | 1 |
| Monitoring | WiFi + 4G dongle, Modbus TCP for third-party EMS, 5-year data retention on the DLXN-IOT platform. | 1 |
How it connects
One array, one inverter, one battery bank, and three possible AC sources. The drawing below is the flow an installer works from; the numbered steps are the order the work actually happens in on site.
Arrows show power flow. The inverter decides every few milliseconds whether the array feeds the loads, charges the battery, exports, or blends all three.
- 1
Mount and earth the array
Rails first, then modules, then a continuous earth bond across every frame. 15 modules at 550 W is 8,250 Wp of DC; the frames must be bonded to the same earth bar as the inverter or the surge protection has nothing to divert into.
- 2
Wire the strings to the combiner
15 x 550 W monocrystalline half-cell, 8S1P + 7S1P on separate MPPT inputs. Each string lands on its own fused or breaker-protected input in the DC combiner, with a Type 2 surge arrester on the DC bus. Check polarity with a meter before the first MC4 click — reversed strings are the most common cause of a dead MPPT on commissioning day.
- 3
Run DC to the inverter MPPT inputs
8 modules (Voc about 400 V, Isc about 14 A) on MPPT 1 and 7 modules (Voc about 350 V) on MPPT 2. Both strings run at roughly 4 kW, which keeps each tracker inside its own current limit and avoids the asymmetric loading that shows up as one hot string on thermal inspection. Keep the DC run as short as the building allows; every extra 10 m of 6 mm2 cable costs roughly 0.3% of yield.
- 4
Set the battery on its own breaker
The DLXN-SL5314 (16.08 kWh, 51.2 V / 314 Ah) connects to the inverter DC bus through its own DC breaker and a pre-charge resistor. Neutral, earth and the battery negative are kept separate; the BMS CAN lead is landed on the inverter comms port and the protocol selected in the menu before the first charge.
- 5
Build the AC side
Inverter AC out feeds a distribution board with an RCD, one breaker per circuit, and a surge arrestor. Grid and generator each get their own input with a changeover, so the inverter can be told which source is present rather than guessing.
- 6
Configure, then load test
Set battery type to lithium, capacity to 16.08 kWh, charge current to the value in the commissioning sheet, and export limit to the site rule (zero-export for prepaid meters). Then apply a known load — a 2 kW kettle is the usual choice — and confirm the inverter holds frequency and voltage while the array is curtailed.
- 7
Hand over the labels and the diagram
Every breaker gets a label, the single-line diagram goes inside the DB door, and the monitoring account is transferred to the owner. This is what an inspector asks for, and it is what the next technician needs two years later.
How much it generates
Daily yield is calculated as 8.25 kWp x irradiance x 0.75 system efficiency. The efficiency factor is not a marketing number: it bundles inverter conversion, DC and AC cable losses, soiling, mismatch and temperature derating at roughly 35 degrees cell temperature.
| Market | Irradiance (kWh/m2/day) | Daily (kWh) | Monthly (kWh) | Yearly (kWh) | What that covers |
|---|---|---|---|---|---|
| South Africa | 5.5 | 34 | 1,020 | 12,410 | about 2.8 kWh/day of self-consumption, or roughly 51% of a 20 kWh/day household |
| Nigeria | 5 | 30.9 | 927 | 11,279 | about 2.6 kWh/day of self-consumption, or roughly 46% of a 20 kWh/day household |
| Philippines | 4.5 | 27.8 | 834 | 10,147 | about 2.3 kWh/day of self-consumption, or roughly 42% of a 20 kWh/day household |
Estimates, not guarantees. Real output moves with tilt, azimuth, shading, soiling and season; a site survey typically shifts these figures by 10-15% either way. Peak-sun-hours data is long-term average, so a good month can beat the table by 20% and a bad one can miss it by 25%.
Usable battery
14.47 kWh
at 90% depth of discharge
Night autonomy at 400 W
36.2 h
excluding air conditioning
Storage per kWp
1.9 kWh/kWp
about 2 kWh/kWp suits daily cycling
How to read the table
The three markets are the ones we ship to most, and the differences are real: Johannesburg gets about 5.5 peak sun hours a year-round, Lagos about 5.0 with a rainy-season dip in June, Manila about 4.5 with a pronounced wet season from June to October. A system sized on the annual average will under-perform in Manila in August and over-perform in March — that is normal, and it is why the battery is sized on the evening load rather than on the daily average.
What it solves
Three load profiles this kit actually gets ordered for. The numbers come from our own commissioning sheets, not from a catalogue.
A four-bedroom house with two air conditioners
Daytime: two 1.5 kW split units at 70% modulation (2.1 kW), a pool pump (1.1 kW) and 400 W of base load is 3.6 kW — covered by the array with 5 kW to spare. Evening: 700 W of lights, fridge, TV and fans for 20 hours on the bank, or 8 hours if one air conditioner stays on.
A guesthouse with six rooms
Six rooms with lights, fans, kettles and a shared laundry draw 1.4 kW in the evening peak. The bank carries 11 hours, longer than the peak itself, and the 8.25 kWp array reheats the geyser and runs the laundry by day at zero marginal cost. Owners typically meter rooms separately and cap each at 2 kWh/day.
A workshop that cannot lose a cut
A 2.2 kW table saw, a 1.5 kW welder and dust extraction draw 4.5 kW intermittently. The 8 kW inverter rides the duty cycle, and the battery absorbs the welder surge so the lights do not flicker. Output per shift is roughly 12 kWh, which the array replaces by early afternoon.
Where this kit is installed
In South Africa this size often goes onto a three-phase supply with one phase dedicated to the inverter, which is why we ask for the DB photo before quoting. Nigerian installations usually pair it with a 10 kVA generator on the AC input; Philippine installations in coastal provinces add the salt-spray corrosion package and a 250 km/h wind rating on the frame.
Indicative EXW cost
Ex-works Shenzhen, USD, per kit. The inverter is quoted separately because it is the one line that changes with your grid and generator; everything else below is fixed hardware.
| Item | Specification | Indicative range |
|---|---|---|
| 8,250 Wp of PV modules | 15 x 550 W mono half-cell | USD 1,403 - 1,898 |
| Battery, 16.08 kWh | DLXN-SL5314, LiFePO4, 51.2 V / 314 Ah | USD 1,528 - 2,090 |
| Mounting, cabling, combiners, AC board | Rails, clamps, DC/AC cable, SPD, DB | USD 240 - 330 |
| Hybrid inverter | 8 kW / 48 V hybrid inverter, 2 x MPPT, 160 A charger | Quoted separately — specification depends on grid and generator |
| Kit total, EXW, excluding inverter | Panels + battery + balance of system | USD 3,171 - 4,318 |
Indicative EXW only — final installed price is quoted by your local installer after freight, duty, labour and commissioning. Module pricing is based on USD 0.17-0.23/Wp and battery on USD 95-130/kWh at the time of writing; both move with cell and wafer prices, so confirm before you budget.
Upgrade path
Upgrade path: a second SL5314 for 32.16 kWh, or two F5400 for 40.96 kWh; three more modules take the array to 9.9 kWp, which is the practical ceiling for this inverter in a hot climate. For three-phase premises, plan the change to the 10 kW three-phase kit instead of paralleling single-phase units.
Hardware in this kit
Every line above maps to a catalogue page with a datasheet:
Frequently asked questions
How much does an 8 kW system with 16 kWh of battery cost?
Indicative EXW: USD 1,403-1,898 for 8.25 kWp of modules, USD 1,528-2,090 for the 16.08 kWh LFP battery, and USD 240-330 for mounting, combiners and cabling — USD 3,170-4,318 before the inverter, which is quoted separately. Installed price will include freight, duty, labour, a CoC or equivalent sign-off and the installer margin; that figure comes from your installer, not from us.
What does an 8 kW array produce per day in these markets?
About 34.0 kWh/day in South Africa, 30.9 in Nigeria and 27.8 in the Philippines at a 0.75 efficiency factor. Monthly: 1,020 / 927 / 834 kWh. That is enough to cover a 25-30 kWh/day household almost entirely, with the surplus going into the 16 kWh bank.
Can it start a borehole pump while the air conditioners are running?
Yes, if the pump is soft-started or the inverter is set to generator-assist. A 2.2 kW direct-on-line pump pulls 6-9 kW for under a second; the 8 kW hybrid covers that with two 1.5 kW air conditioners already at 2.1 kW because its surge rating is roughly double its continuous rating. A 5 kW unit in the same situation will trip — that is the main reason customers move up to this kit.
Is 16 kWh of storage the right size for an 8 kW array?
For daily cycling, yes: it is about 2 kWh per kWp, which absorbs the midday surplus and returns it at night without sitting full for days. If your goal is multi-day autonomy rather than daily arbitrage, double it — but be aware that a bank sized for three days sits at high state of charge most of the year, which is harder on LFP cells than daily cycling.
Ask about this configuration
Send us your load list, the port you ship to and whether a generator stays on site. We reply with a configuration, a drawing and an EXW quotation — usually within one business day.
- ✉ dlxn@dlxnsolar.com
- Contact details and offices
- Factory: Shenzhen, China · Ports: Shenzhen / Ningbo / Shanghai
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