Day-night battery
Stores the daytime surplus for the following night.
- Self-sufficiency
- 85%
- Self-consumption
- 71%
- Battery size
- 1.9 kWh/kWp
Ghana bills businesses by the kWh only: $0.183 per kWh on the medium-voltage commercial tariff, with no capacity charge. Exported energy earns $0.071 per kWh under the 60/40 net-billing regime, capped at 500 kW per customer. With 22 outage hours in a normal year and diesel generation at $0.500 per kWh, the battery earns first as backup and second on self-consumption.
Primary-source values, each with its source and confidence level.
Ten factors that decide how attractive a market is for a business installing solar, a battery and chargers — scored on primary-source data, not on opinion.
Solar autonomy scorecard · Modelled estimate
With PV sized at 120% of annual consumption, a battery that carries one night covers 85% of the demand in Ghana; a battery holding three days of consumption lifts that to 100%.
Generation is almost flat through the year: the strongest month yields 1.2× the weakest, so there is no season to bridge.
Even in the three leanest months practically nothing is left uncovered.
Businesses pay on average 0.137 USD per kWh, households 0.147 USD per kWh.
The configurator for Ghana calculates with 1,600 kWh/kWp, a site-specific reference (Global Solar Atlas, PVOUT for Accra). This scorecard uses 1,500 kWh/kWp, a rounded national estimate, so that all countries are compared on the same basis. Its seasonal figures likewise come from the climate model, not from the site-specific monthly profile above.
The market facts above use the tariff a medium-sized business actually pays in Ghana: $0.183 per kWh. The business price in this scorecard is a cross-country average over all business tariff classes, used only to compare countries.
Both with PV sized at 120% of annual consumption.
Stores the daytime surplus for the following night.
Holds three full days of consumption, to ride through overcast spells.
Share of the annual total per month. Modelled from latitude and climate class, not measured.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| PV yield (%) | 7.6 | 8.1 | 8.6 | 8.8 | 8.7 | 8.6 | 8.6 | 8.8 | 8.7 | 8.3 | 7.7 | 7.4 |
| Consumption (%) | 7.9 | 7.9 | 8.3 | 8.7 | 8.7 | 8.7 | 8.7 | 8.7 | 8.7 | 8.3 | 7.9 | 7.9 |
Even in the three leanest months practically nothing is left uncovered.
The same fields as the downloadable dataset, with their definition.
| Variable | Value | Definition |
|---|---|---|
Continentcontinent | Africa | Continent the country belongs to. |
Countrycountry | Ghana | 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 | 0.147 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 | 0.137 USD/kWh USD/MWh | Average all-in retail price for businesses, national average. Empty where the source publishes no business price. |
PV yieldpv_yield_kwh_kwp | 1,500 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 | 7.4% | 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 | 8.8% | Share of the annual yield produced in the strongest of the twelve months. |
Seasonal spreadseasonal_spread | 1.2× | 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 | 71% | 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 | 85% | 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 | 1.9 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 | 83% | 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 | 100% | 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 | 10.3 kWh/kWp | Battery capacity equal to three days of consumption, per kWp of PV. |
Consumption profileconsumption_profile | near-flat (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 | 0% | 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 | 0 kWh/kWp | The same deficit expressed in kWh per kWp of PV. |
Latitudelatitude | 7.5 ° | Representative latitude used by the astronomical yield model; negative is the southern hemisphere. |
Climate classclimate | tropical wet | Climate class that sets the monthly cloud pattern, day-to-day variability and consumption profile. |
Monthly yield sharesmonthly_yield_share_pct | 7.6 · 8.1 · 8.6 · 8.8 · 8.7 · 8.6 · 8.6 · 8.8 · 8.7 · 8.3 · 7.7 · 7.4 | 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 | 7.9 · 7.9 · 8.3 · 8.7 · 8.7 · 8.7 · 8.7 · 8.7 · 8.7 · 8.3 · 7.9 · 7.9 | Twelve values, January to December: assumed share of the annual consumption per month. |
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.
PV sized at 120% of annual consumption; 55% of consumption falls outside direct sun hours; battery round-trip efficiency 92%.
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.
Seven groups of country variables drive the model. Each value carries its source and a confidence level; the ones still open are shown as such — never hidden behind a default.
Installation, permits and after-sales run through our local partner; Solarnation designs, sizes and finances. Your case study is handed over to them after the last step.
Local partner to be announced.
Every answer is a fact from the dataset above, with its source.
$0.183 per kWh for a medium-voltage commercial customer, plus a service charge of about $526 per year. There is no capacity or demand charge under the 2026-2030 tariff decision.
Source: PURC SLT-MV tariff, Q3 2026
Ghana runs net-billing rather than one-to-one net metering: exported energy is credited at about 40% of the retail rate — $0.071 per kWh — and the Net Metering Code 2023 caps eligible systems at 500 kW per customer.
Source: Energy Commission, Net Metering Code 2023
Solar panels and inverters carry 0% import duty. Lithium-ion batteries carry 10%, and VAT of 15% applies to batteries.
Source: Ghana Revenue Authority customs tariff; VAT Act 1151
Usually yes, and first as backup: ECG reports about 22 outage hours a year in Accra in a normal year, rising to roughly 670 in a crisis year, while diesel generation costs around $0.500 per kWh. Self-consumption of solar comes second, and the configurator co-simulates both on one battery.
Source: ECG SAIDI via PURC; NPA fuel price windows
It depends on your load profile and your roof, which is why we do not quote a single number. The main drivers are the $0.183 per kWh tariff, displaced diesel and the 500 kW net-billing limit; the configurator computes payback and IRR from your own consumption in about five minutes.
US dollars with an indicative Ghana cedi conversion at 11.4 GHS per USD, in English. All amounts exclude VAT.
Source: Bank of Ghana interbank rate
With PV sized at 120% of annual consumption, a battery that carries one night covers 85% of the demand in Ghana; a battery holding three days of consumption lifts that to 100%. Even in the three leanest months practically nothing is left uncovered.
Per kWp of PV, carrying one night takes about 1.9 kWh of battery and holding three days of consumption about 10.3 kWh. With the three-day battery, self-sufficiency reaches 100%.
A well-oriented system yields about 1,500 kWh per kWp a year. The strongest month produces 1.2× the weakest: 8.8% against 7.4% of the annual yield.