Day-night battery
Stores the daytime surplus for the following night.
- Self-sufficiency
- 90%
- Self-consumption
- 75%
- Battery size
- 2.5 kWh/kWp
Solar autonomy scorecard · Modelled estimate
Can a business in Namibia run on solar and a battery?
With PV sized at 120% of annual consumption, a battery that carries one night covers 90% of the demand in Namibia; a battery holding three days of consumption lifts that to 98%.
Generation is moderately seasonal: the strongest month yields 2.1× the weakest.
In the three leanest months 1.3% of the annual consumption stays uncovered — a gap a generator or a modest grid connection can fill.
Households pay on average 0.143 USD per kWh; the source publishes no business price.
- Electricity price, businesses
- —not published
- Electricity price, households
- 0.143USD/kWh
- PV yield
- 2,000kWh/kWp
- Seasonal spread
- 2.1×strongest ÷ weakest month
- Three-day battery
- 13.7kWh/kWp
- Lean-season deficit
- 1.3%of annual consumption
Two battery scenarios
Both with PV sized at 120% of annual consumption.
Three-day battery
Holds three full days of consumption, to ride through overcast spells.
- Self-sufficiency
- 98%
- Self-consumption
- 81%
- Battery size
- 13.7 kWh/kWp
Generation and demand through the year
Share of the annual total per month. Modelled from latitude and climate class, not measured.
- Weakest month
- 5.4%
- Strongest month
- 11.6%
- Seasonal spread
- 2.1×
- Consumption profile
- summer peak (cooling)
- Climate class
- desert
PV yield / Consumption — Namibia
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| PV yield (%) | 11.4 | 10.3 | 8.6 | 6.4 | 6.0 | 5.4 | 5.7 | 5.8 | 7.9 | 9.8 | 11.1 | 11.6 |
| Consumption (%) | 10.2 | 10.2 | 9.4 | 8.1 | 7.3 | 6.9 | 6.9 | 6.9 | 7.3 | 8.1 | 8.9 | 9.8 |
A lean season to cover
In the three leanest months 1.3% of the annual consumption stays uncovered — a gap a generator or a modest grid connection can fill.
Sensitivity: what changes the outcome
One parameter varied at a time against the base run.
| Parameter | Value | Day-night | Three-day | Deficit |
|---|---|---|---|---|
| base | 120% · 55% · 92% | 90% | 98% | 1.3% |
| PV oversizing | 100% | 85% | 91% | 4.4% |
| PV oversizing | 150% | 94% | 100% | 0.0% |
| Night fraction of consumption | 45% | 91% | 98% | 1.2% |
| Night fraction of consumption | 65% | 89% | 97% | 1.5% |
| Battery round-trip efficiency | 85% | 87% | 96% | 2.1% |
| Battery round-trip efficiency | 96% | 92% | 98% | 0.9% |
Going from 120% to 150% PV moves three-day self-sufficiency by only 2 points: the signature of a seasonal problem, not a sizing problem.
Every modelled value for Namibia
The same fields as the downloadable dataset, with their definition.
| Variable | Value | Definition |
|---|---|---|
Continentcontinent | Africa | Continent the country belongs to. |
Countrycountry | Namibia | Country name in English. |
Regionregion | — | Climate region within the country; empty when the country is modelled as one region. |
Electricity price, householdsprice_households_usd_mwh | 0.143 USD/kWh USD/MWh | Average all-in retail price for households, national average. Static average, not a dynamic or market price. |
Electricity price, businessesprice_businesses_usd_mwh | not published | Average all-in retail price for businesses, national average. Empty where the source publishes no business price. |
PV yieldpv_yield_kwh_kwp | 2,000 kWh/kWp/year | Estimated annual yield of a well-oriented PV system per installed kWp, rounded to the nearest fifty. |
Weakest month shareweakest_month_share_pct | 5.4% | Share of the annual yield produced in the weakest of the twelve months (the wet season in monsoon climates, winter elsewhere). A perfectly flat year gives one twelfth per month. |
Strongest month sharestrongest_month_share_pct | 11.6% | Share of the annual yield produced in the strongest of the twelve months. |
Seasonal spreadseasonal_spread | 2.1× | Strongest month divided by weakest month. Close to one means flat generation all year; above ten means strongly seasonal. |
Self-consumption, day-night batteryself_consumption_daynight_pct | 75% | Share of the PV generation that is used on site with a battery sized to carry one night. Equals self-sufficiency divided by the oversizing factor. |
Self-sufficiency, day-night batteryself_sufficiency_daynight_pct | 90% | Share of the annual consumption covered by PV plus a battery sized to carry one night. Never above one hundred percent. |
Battery size, day-nightbattery_daynight_kwh_kwp | 2.5 kWh/kWp | Battery capacity needed to carry the night-time share of one day of consumption, per kWp of PV. |
Self-consumption, three-day batteryself_consumption_3day_pct | 81% | Share of the PV generation that is used on site with a battery holding three days of consumption. |
Self-sufficiency, three-day batteryself_sufficiency_3day_pct | 98% | Share of the annual consumption covered by PV plus a battery holding three days of consumption. This is the figure the energy-island assessment is based on. |
Battery size, three-daybattery_3day_kwh_kwp | 13.7 kWh/kWp | Battery capacity equal to three days of consumption, per kWp of PV. |
Consumption profileconsumption_profile | summer peak (cooling) | Assumed seasonal shape of demand for the climate: winter peak (heating), summer peak (cooling), double peak or near-flat. |
Lean-season deficitwinter_deficit_pct | 1.3% | Demand that stays unmet during the three consecutive lowest-yield months, despite the three-day battery, as a share of annual consumption. It is what remains for the grid, a backup generator or seasonal storage. |
Lean-season deficit, absolutewinter_deficit_kwh_kwp | 22.4 kWh/kWp | The same deficit expressed in kWh per kWp of PV. |
Latitudelatitude | -22 ° | Representative latitude used by the astronomical yield model; negative is the southern hemisphere. |
Climate classclimate | desert | Climate class that sets the monthly cloud pattern, day-to-day variability and consumption profile. |
Monthly yield sharesmonthly_yield_share_pct | 11.4 · 10.3 · 8.6 · 6.4 · 6.0 · 5.4 · 5.7 · 5.8 · 7.9 · 9.8 · 11.1 · 11.6 | Twelve values, January to December: share of the annual PV yield per month. Modelled from latitude and climate class, not measured. |
Monthly consumption sharesmonthly_consumption_share_pct | 10.2 · 10.2 · 9.4 · 8.1 · 7.3 · 6.9 · 6.9 · 6.9 · 7.3 · 8.1 · 8.9 · 9.8 | Twelve values, January to December: assumed share of the annual consumption per month. |
How the model works
Monthly PV yield comes from an astronomical model (latitude, declination, tilt) multiplied by a climate pattern for cloud and rain. Day-to-day variability follows a gamma distribution per climate; multi-day coverage is the sum of independent days. Seasonal consumption is set per climate: a winter peak for heating, a summer peak for cooling, a double peak in Mediterranean climates.
Fixed assumptions
PV sized at 120% of annual consumption; 55% of consumption falls outside direct sun hours; battery round-trip efficiency 92%.
What it is not
An analytical approximation, not an hourly simulation of your site. Prices are static national averages, not dynamic or market prices. The deficit is not a storage recommendation: it quantifies what remains for grid, backup or seasonal storage.
Sources
- Electricity prices: national averages, Q2 2026.
- PV yield: Estimates in line with Global Solar Atlas (World Bank / Solargis), rounded to the nearest 50 kWh/kWp.
- Licence: CC BY 4.0.
- Dataset updated 2026-09-22
From country average to your own roof
The configurator is not live for Namibia yet. See where it runs today, or ask us to model your site.
Namibia — solar autonomy in short
Can a business in Namibia go off-grid with solar and a battery?
With PV sized at 120% of annual consumption, a battery that carries one night covers 90% of the demand in Namibia; a battery holding three days of consumption lifts that to 98%. In the three leanest months 1.3% of the annual consumption stays uncovered — a gap a generator or a modest grid connection can fill.
How large a battery does solar autonomy take in Namibia?
Per kWp of PV, carrying one night takes about 2.5 kWh of battery and holding three days of consumption about 13.7 kWh. With the three-day battery, self-sufficiency reaches 98%.
How much does solar generation in Namibia vary between seasons?
A well-oriented system yields about 2,000 kWh per kWp a year. The strongest month produces 2.1× the weakest: 11.6% against 5.4% of the annual yield.
What does electricity cost in Namibia?
Households pay on average 0.143 USD per kWh; the source publishes no business price.