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    Fct State

    Rooftop solar in Bwari, Fct: what the roofs are worth

    Bwari has 291,991 buildings with a viable rooftop and 4.92m kWp of roof capacity. 32% run a generator, and together they spend ₦148bn a year on energy.

    Viable buildings

    291,991

    Usable roof area

    21.9m m²

    4.92m kWp roof capacity

    Energy spend

    ₦148bn/yr

    118m kWh/yr burned on generators

    Median payback

    5.9 yr

    Median IRR 19% (cash saved)

    The savings bracket for Bwari

    Approach B

    Cash saved

    What these buildings stop paying — merit order, capped at current spend.

    Current energy spend₦148bn/yr
    Year-one cash saved₦142bn
    Lifetime cash saved₦6.15tn
    NPV₦891bn
    Median IRR19%
    Median payback5.9 yr
    Unlocked energy169m kWh/yr
    Approach A

    Energy value (upper bracket)

    What the energy is worth if full latent demand were met. Not cash saved.

    Installed capacity740k kWp
    Capex₦687bn
    Year-one energy value₦489bn
    Lifetime energy value₦22.3tn
    NPV₦3.64tn
    Median IRR73%
    Median payback1.4 yr

    Three ways to size Bwari's rooftops

    Solar + battery. The default headline scenario, and the one the SEO fact base quotes. Prices the energy a full solar+storage system would deliver.

    Baseline: mixed
    Counterfactual: grid when available, generator otherwise, weighted by the NTL-derived grid availability. The realistic case, and what the headline numbers use. Always falls between grid and genset by construction.

    Read with care: Sized to LATENT demand — the energy the building would use if it could. Against a cash baseline that only reflects today's spend this looks oversized; that is what sc3 exists to fix.

    System size
    740k kWp
    Capital cost
    ₦687bn
    Year 1 savings
    ₦489bn/yr
    NPV
    ₦3.64tn
    Median IRR
    73%
    Median payback
    1.4 yr

    How many rooftops in Bwari actually pay

    Counted building by building on the cash-saved basis (merit-order sized, valued against what the building spends today), not read off an average. 291,991 of 291,991 clear a positive NPV.

    Payback

    Under 3 years64,369 (22%)
    Under 5 years99,711 (34%)
    Under 7 years291,991 (100%)
    Under 10 years291,991 (100%)

    Return (IRR)

    Above 10%291,991 (100%)
    Above 15%291,991 (100%)
    Above 20%104,076 (36%)
    Above 25%83,083 (28%)
    CO₂ avoided

    294m kg/yr

    Fuel avoided

    59.1m L/yr

    Energy unlocked

    169m kWh/yr

    Demand that is suppressed today

    People served

    512k

    What hardware costs right now

    Median advertised rates from our Nigerian market tracker — the same prices used to cost a system in Bwari.

    Solar panels

    250

    ₦/W

    Inverters

    127,419

    ₦/kVA

    Batteries

    177,500

    ₦/kWh

    Building mix in Bwari

    Load profile

    SegmentBuildings With generator Spend ₦/yr Cash saved yr 1 (B) Median IRR Median payback
    Residential271,20186,357₦87bn₦82.6bn19%5.9 yr
    Commercial General9,8593,547₦43.1bn₦41.8bn25%4.4 yr
    Commercial Retail8,7212,814₦1.38bn₦1.38bn25%4.4 yr
    Anchor1,095385₦15.2bn₦14.8bn33%3.4 yr
    Worship702319₦320m₦320m25%4.4 yr
    Hospitality18751₦671m₦666m25%4.4 yr
    Industrial16357₦435m₦428m27%4.1 yr
    Mall Retail249₦45.1m₦45.1m25%4.4 yr
    Productive Use226₦13m₦13m25%4.4 yr
    Filling Station114₦18m₦18m25%4.4 yr
    Automotive61₦10.2m₦10.2m21%5.1 yr

    Roof size band

    SegmentBuildings With generator Spend ₦/yr Cash saved yr 1 (B) Median IRR Median payback
    Under 30m287,14632,060₦2.58bn₦2.45bn19%5.9 yr
    100 250m272,75522,572₦44.9bn₦43.8bn19%5.9 yr
    50 100m270,02517,775₦10.2bn₦9.61bn19%5.9 yr
    30 50m242,83713,489₦2.64bn₦2.53bn19%5.9 yr
    250 1000m218,6897,349₦62bn₦58.6bn19%5.9 yr
    Over 1000m2539305₦25.9bn₦25.1bn27%4.1 yr

    Settlement type

    SegmentBuildings With generator Spend ₦/yr Cash saved yr 1 (B) Median IRR Median payback
    Urban Centre225,74644,885₦86bn₦83.3bn19%5.9 yr
    Urban29,38119,824₦30.9bn₦28.8bn45%2.4 yr
    Unclassified28,40422,627₦24.2bn₦22.9bn59%1.9 yr
    Dense Urban4,9892,925₦5.42bn₦5.33bn33%3.1 yr
    Rural3,4713,289₦1.84bn₦1.81bn73%1.4 yr

    Lead segment

    SegmentBuildings With generator Spend ₦/yr Cash saved yr 1 (B) Median IRR Median payback
    Standard282,48989,983₦92.5bn₦88.1bn19%5.9 yr
    SME High8,3813,167₦40.4bn₦39.1bn25%4.4 yr
    Enterprise1,121400₦15.4bn₦15bn33%3.4 yr

    Demand tier

    SegmentBuildings With generator Spend ₦/yr Cash saved yr 1 (B) Median IRR Median payback
    4.094,93411,030₦21.7bn₦21.3bn
    3.076,41730,456₦82.7bn₦78.5bn
    2.053,24516,628₦7.49bn₦6.97bn
    0.044,64127,856₦1.81bn₦1.81bn
    1.017,2415,675₦1.37bn₦1.33bn
    5.04,2261,271₦10bn₦9.69bn
    6.01,287634₦23.2bn₦22.6bn

    Nearby LGAs in Fct

    How these numbers are produced

    Approach A — energy value (upper bracket)

    Sizes the system to the building's full latent demand and values that energy at the mixed grid/generator tariff. It answers what the energy is worth — not what anyone currently pays.

    Approach B — cash saved (lower bracket)

    Sizes the system to demand that is actually served today, values it by merit order (solar displaces generator kWh first) and caps it at current spend. It answers what a building stops paying.

    Cohort: Viable rooftops (≥0.6 kWp potential).

    • Demand is modelled latent demand, not metered consumption.
    • Fuel is priced at ₦1,800/litre (operator-set). NBS reported ₦3,277/litre for May 2026 — on that basis every naira figure here is roughly 1.8× understated.
    • Generator ownership is a model output, not a survey result: it follows from the grid-availability scale and the 25% demand-suppression assumption.
    • Approach A prices energy nobody currently buys. Its savings must never be read as cash saved.
    • Demand is MODELLED LATENT demand, not metered consumption.
    • Generator ownership is model output, not survey.
    • Medians do not combine across groups — re-derive from the histograms.
    • Per-building files are float32 with 4 significant figures; cast to float64 before summing, because polars keeps Float32 sums in Float32.
    • Null scenario fields mean the roof cannot host 0.6 kWp, not zero savings.
    • `genset` was previously named `diesel` and now uses the segment's real fuel.
    • Ordering holds by construction: grid savings < mixed < genset.