For remote sites & diesel-dependent facilities
Off-grid Solar
Diesel-free power where the grid doesn't reach.
A self-contained solar plant — panels, charge control, LFP battery bank and inverter — sized to carry your load day and night without a utility connection. Your genset moves from daily workhorse to last-resort standby.
220 kWp off-grid · Sylhet
- System size
- 5 – 500 kWp
- Replaces diesel at
- Tk 28–32 / kWh
- Payback vs diesel
- 2.5 – 4 yrs
- Battery autonomy
- 12 – 36 h
Who it's for
For sites the grid never reached — or keeps failing.
If a diesel genset is your main source of electricity, every unit costs you Tk 28–32 before maintenance. Off-grid solar replaces most of those units with sunlight you store.
Grid-connected but tired of outages? Hybrid solar usually pays back faster.
Remote sites
Tea estates, char-land farms, island and hill-tract facilities several kilometres from a usable feeder.
No feeder within reach
Grids you can't trust
REB and PBS areas where outages run for hours every day and voltage swings burn out motors.
Genset runs every day
Rural processing & cold chain
Rice mills, hatcheries, cold storage and agro-processing where diesel is the largest operating cost.
Diesel > 30% of opex
Clinics, schools & pump stations
Health complexes, schools, telecom sites and irrigation pumps that need quiet, fuel-free supply.
Small, critical loads
System architecture
Five components. No utility in the loop.
Energy moves one way through the day: from the roof, into storage, out to your loads. Every stage is monitored remotely.
- Solar arrayTier-1 modulesDC
- Charge controllerMPPT · DC-coupledCharge
- LFP battery bankDay + night storageDC bus
- Off-grid inverterPure sine · 3-phase400 V AC
- Site loadsMotors, cold rooms, lights
- 01Solar arrayTier-1 modules on roof, ground or carport structures, strung for the controller's voltage window.
- 02MPPT charge controllerTracks the maximum power point of every string and charges the battery without overcharging it.
- 03LFP battery bankStores daytime surplus for night and cloudy days; the BMS protects every cell from heat and deep discharge.
- 04Off-grid inverterForms a stable 230/400 V supply with the surge headroom motors and compressors need to start.
- 05Your loadsCritical circuits are prioritised; an existing genset stays wired in as automatic standby.
Component specification
What goes into a plant that has to run alone.
No grid to fall back on means no weak link. Every component is IEC-certified and chosen for heat, humidity and remote serviceability.
Download Capability Profile| Solar array | |
|---|---|
| Modules | Tier-1 mono PERC / TOPCon, 550–620 WpIEC 61215 / 61730, PID-resistant |
| Mounting | Hot-dip galvanised steel or anodised aluminiumRoof, ground or carport |
| Wind design | BNBC 2020 basic wind speed for the district |
| Charge control | |
| Controller | MPPT, 98–99% tracking efficiency |
| DC protection | String fuses, DC isolators, Type II surge protection |
| Battery bank | |
| Chemistry | LiFePO₄ (LFP), rack or cabinet mounted |
| Usable capacity | 10 kWh – 1 MWhSized on the worst monsoon month |
| Cycle life | 6,000+ cycles at 80% depth of discharge |
| Management | Cell-level BMS, thermal and short-circuit protection |
| Inverter | |
| Rating | 5–250 kW, single- or three-phase, pure sine wave |
| Surge capacity | 2–3× rated power for 5 sMotor and compressor starts |
| Genset input | Automatic start on low battery state of charge |
| Monitoring & warranty | |
| Monitoring | 4G remote portal, SMS alarms, monthly report |
| Earthing | Lightning protection and earthing to IEC 62305 |
| Warranties | Modules 12 yrs · battery 10 yrs / 6,000 cycles · inverter 5 yrsExtendable under AMC |
Sizing by load profile
Sized to your load, not a catalogue.
Four reference designs. Your survey replaces these with your own measured load curve and worst-month yield.
- Rural clinic or schoolDaytime-heavy, lights, fans, cold chain
- Daily energy
- 40 kWh
- PV array
- 15 kWp
- Battery (usable)
- 25 kWh
- Inverter
- 10 kW
- Diesel displaced / yr
- ~3,700 L
- Indicative capex
- Tk 15 lakh
- Payback
- 3–3.5 yrs
- Poultry farm or hatchery24-hour ventilation and incubators
- Daily energy
- 120 kWh
- PV array
- 45 kWp
- Battery (usable)
- 80 kWh
- Inverter
- 25 kW
- Diesel displaced / yr
- ~11,000 L
- Indicative capex
- Tk 46 lakh
- Payback
- 3–4 yrs
- Agro or rice millSingle daytime shift, motor loads
- Daily energy
- 350 kWh
- PV array
- 130 kWp
- Battery (usable)
- 150 kWh
- Inverter
- 80 kW
- Diesel displaced / yr
- ~32,000 L
- Indicative capex
- Tk 1.1 crore
- Payback
- 2.5–3 yrs
- Tea estate factoryWithering & drying, day and night
- Daily energy
- 600 kWh
- PV array
- 220 kWp
- Battery (usable)
- 600 kWh
- Inverter
- 150 kW
- Diesel displaced / yr
- ~41,000 L
- Indicative capex
- Tk 2.9 crore
- Payback
- 3.5–4 yrs
| Load profile | Daily energy | PV array | Battery (usable) | Inverter | Diesel displaced / yr | Indicative capex | Payback |
|---|---|---|---|---|---|---|---|
| Rural clinic or schoolDaytime-heavy, lights, fans, cold chain | 40 kWh | 15 kWp | 25 kWh | 10 kW | ~3,700 L | Tk 15 lakh | 3–3.5 yrs |
| Poultry farm or hatchery24-hour ventilation and incubators | 120 kWh | 45 kWp | 80 kWh | 25 kW | ~11,000 L | Tk 46 lakh | 3–4 yrs |
| Agro or rice millSingle daytime shift, motor loads | 350 kWh | 130 kWp | 150 kWh | 80 kW | ~32,000 L | Tk 1.1 crore | 2.5–3 yrs |
| Tea estate factoryWithering & drying, day and night | 600 kWh | 220 kWp | 600 kWh | 150 kW | ~41,000 L | Tk 2.9 crore | 3.5–4 yrs |
Indicative only. Basis: 1,300 kWh/kWp/yr derated for the monsoon month, LFP at 80–90% depth of discharge, diesel at ~0.28 L/kWh and Tk 28–32/kWh. Tea estate row reflects our Sylhet project.
Installation timeline
Survey to switch-on in about 14 weeks.
A typical 130 kWp programme. Remote sites add one to three weeks for logistics; the genset keeps running until commissioning.
01Site survey & load audit
Emerged engineering
02Design & battery sizing
PVsyst + autonomy model
03Procurement
Modules, LFP, inverters
04Civil & mounting structure
Site team
05Electrical & battery room
Site team
06Testing & commissioning
Emerged engineering
07Handover & operator training
O&M team
Cost & payback
The cheapest diesel is the diesel you don't burn.
Off-grid solar costs more upfront than a genset, but each unit it delivers costs roughly a third as much. Fuel savings typically repay the plant in two and a half to four years.
Ways to pay
- 01Capex purchaseOwn the plant outright; the fastest route to the lowest lifetime cost.
- 02Lease-to-ownSpread the cost over 36–60 months so fuel savings fund the instalments.
- 03Green financeWe prepare the technical file for IDCOL and bank green-refinance applications.
Cost per unit of electricity
Tk per kWh. Diesel includes fuel and genset O&M; solar is levelised over 20 years.
Worked example · 130 kWp agro mill
- Indicative capex
- Tk 1.1 crore
- Diesel avoided
- ~32,000 L / yr
- Fuel + genset O&M saved
- ~Tk 38 lakh / yr
- Simple payback
- ~2.9 yrs
- 20-year net saving
- ~Tk 5.5 crore
Sylhet · February 2025
Case study · Off-grid
220 kWp off-grid system for a tea estate factory
- Result
- 41,000 L
- diesel avoided per year
- Sector
- Industrial
- Client
- Tea estate & processing unit
The challengeA withering-and-drying factory 14 km from the nearest reliable feeder, running on two diesel gensets.
The resultGensets now run under 300 hours a year. Diesel purchases fell by roughly 41,000 litres annually.
Free · no obligation
Find out how much diesel your site can stop burning.
Share your genset logs or fuel bills. We'll size a system to your real load and show the payback against diesel — free.
What you receive
- 01Load audit from genset & fuel records
- 02Sized PV, battery and inverter design
- 03Diesel saving and payback forecast