Nigeria rooftop solar data

Rooftop solar in Osun State: buildings, spend and payback

1,265,982 buildings in Osun State carry a viable rooftop. Together they spend ₦577bn a year on grid power and generator fuel, and 19% of them run a generator.

Viable buildings

1,265,982

Usable roof area

142 km²

32 GWp of roof capacity

Current energy spend

₦577bn/yr

494 GWh/yr from generators

Median payback

4.4 yr

Median IRR 25% (cash saved)

The savings bracket for Osun

Approach B

Cash saved

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

Current energy spend₦577bn/yr

Year-one cash saved₦559bn

Lifetime cash saved₦30.6tn

NPV₦4.45tn

Median IRR25%

Median payback4.4 yr

Unlocked energy567 GWh/yr

Approach A

Energy value (upper bracket)

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

Installed capacity2.59 GWp

Capex₦2.52tn

Year-one energy value₦1.9tn

Lifetime energy value₦89.2tn

NPV₦14.7tn

Median IRR71%

Median payback1.6 yr

Three ways to size Osun State'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: 2.59 GWp
Capital cost: ₦2.52tn
Year 1 savings: ₦1.9tn/yr
NPV: ₦14.7tn
Median IRR: 71%
Median payback: 1.6 yr

The odds a rooftop in Osun State pays back quickly

Of the 1,228,874 buildings in Osun State with a modelled payback, 63.1% pay back inside five years and 19.0% inside three.

Payback under 5 years

63.1%

Payback under 3 years

19.0%

IRR above 20%

66.0%

Under 3 years · 19%3 – 5 years · 44%5 – 7 years · 16%7 – 10 years · 9%Over 10 years · 12%

Coverage: 97% of buildings in Osun State produced a payback figure. Buildings with no viable scenario are excluded rather than counted as zero.

How much of Osun State's demand actually gets met

Buildings in Osun State consume 1.12 TWh/yr but want 1.68 TWh/yr. The 34% they cannot buy is suppressed demand — load that appears the moment supply is reliable.

Met today · 66%Suppressed · 34%

Energy wanted

1.68 TWh/yr

Energy consumed

1.12 TWh/yr

Unmet demand

567 GWh/yr

Modelled latent demand, not metered consumption. It is the load buildings would run given affordable, available supply.

How many rooftops in Osun State 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. Shares are of the 1,228,874 buildings with a modelled result out of 1,265,982 in Osun State. 971,333 clear a positive NPV.

Payback

Under 3 years233,744 (19%)

Under 5 years775,216 (63%)

Under 7 years969,739 (79%)

Under 10 years1,085,480 (88%)

Return (IRR)

Above 10%1,069,717 (84%)

Above 15%971,333 (77%)

Above 20%835,022 (66%)

Above 25%550,517 (43%)

Electricity billing bands in Osun State

Loading band economics…

What a delivered unit costs, by DisCo

Grid tariff plus the generator running that fills the gap, blended across every building the DisCo serves. Ranked most expensive first — the higher the all-in rate, the stronger the case for solar.

Loading the league table…

Ikeja and Eko are reported together as Lagos. Rates are modelled blends of billed grid energy and generator running, not published tariffs.

What hardware costs right now

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

Solar panels

₦250

₦/W

Inverters

₦127,419

₦/kVA

Batteries

₦177,500

₦/kWh

Full price tracker Size a home system Size a business system

Where the opportunity sits

Electricity billing band

Segment	Buildings	With generator	Spend ₦/yr	Cash saved yr 1 (B)	Median IRR	Median payback
C	383,928	69,249	₦125bn	₦124bn	25%	4.4 yr
D	379,250	77,593	₦163bn	₦158bn	25%	4.4 yr
E	292,865	71,519	₦220bn	₦209bn	25%	4.4 yr
B	182,348	23,977	₦60.7bn	₦60.1bn	25%	4.4 yr
A	27,591	2,186	₦8.49bn	₦8.45bn	25%	4.4 yr

Load profile

Segment	Buildings	With generator	Spend ₦/yr	Cash saved yr 1 (B)	Median IRR	Median payback
Residential	1,203,590	210,711	₦350bn	₦335bn	25%	4.4 yr
Commercial General	30,560	16,713	₦117bn	₦116bn	37%	2.9 yr
Commercial Retail	12,529	5,936	₦2.16bn	₦2.16bn	33%	3.4 yr
Anchor	10,979	6,724	₦92.8bn	₦91.6bn	43%	2.4 yr
Industrial	6,166	3,382	₦11.1bn	₦11bn	41%	2.6 yr
Filling Station	798	406	₦802m	₦802m	35%	3.1 yr
Worship	748	346	₦518m	₦518m	35%	3.1 yr
Hospitality	392	179	₦2.01bn	₦1.95bn	35%	3.1 yr
Productive Use	133	96	₦165m	₦165m	43%	2.6 yr
Mall Retail	81	30	₦177m	₦177m	35%	3.1 yr
Automotive	6	1	₦858k	₦858k	29%	3.6 yr

Roof size band

Segment	Buildings	With generator	Spend ₦/yr	Cash saved yr 1 (B)	Median IRR	Median payback
100 250m2	521,205	99,945	₦219bn	₦213bn	25%	4.4 yr
Under 30m2	231,369	44,118	₦6.58bn	₦6.38bn	9%	8.6 yr
50 100m2	218,947	36,771	₦25.5bn	₦24.3bn	21%	5.1 yr
250 1000m2	157,947	38,320	₦238bn	₦229bn	25%	4.4 yr
30 50m2	132,600	24,365	₦7.15bn	₦6.82bn	15%	6.6 yr
Over 1000m2	3,914	1,005	₦80.7bn	₦79.2bn	27%	3.9 yr

Settlement type

Segment	Buildings	With generator	Spend ₦/yr	Cash saved yr 1 (B)	Median IRR	Median payback
Urban Centre	785,001	138,740	₦243bn	₦242bn	25%	4.4 yr
Unclassified	144,676	15,228	₦86.4bn	₦74.9bn	23%	4.6 yr
Dense Urban	130,603	39,917	₦83.5bn	₦83.2bn	25%	4.4 yr
Urban	125,839	37,485	₦132bn	₦129bn	25%	4.4 yr
Rural	45,775	11,659	₦27.7bn	₦26.4bn	23%	4.6 yr
(Unset)	34,088	1,495	₦4.49bn	₦4.49bn	21%	5.4 yr

Building type

Segment	Buildings	With generator	Spend ₦/yr	Cash saved yr 1 (B)	Median IRR	Median payback
Residential Formal	442,422	64,475	₦49.1bn	₦48.9bn	25%	4.4 yr
Residential	217,380	58,900	₦247bn	₦233bn	25%	4.4 yr
Residential Small	167,803	35,352	₦24.8bn	₦23.3bn	23%	4.6 yr
Residential Informal	161,792	16,013	₦15.8bn	₦15.7bn	23%	4.6 yr
Shed	117,244	23,288	₦3.96bn	₦3.96bn	13%	7.4 yr
Apartment	65,411	8,699	₦6.69bn	₦6.69bn	25%	4.4 yr
Duplex	28,851	3,800	₦2.85bn	₦2.77bn	25%	4.4 yr
Kiosk Shop	12,590	5,988	₦2.18bn	₦2.18bn	33%	3.4 yr
Commercial	11,028	6,244	₦48.3bn	₦48.2bn	39%	2.9 yr
Commercial Corridor	9,757	5,066	₦42.7bn	₦42.4bn	35%	3.1 yr
Institutional	9,172	5,181	₦67.4bn	₦67bn	37%	2.9 yr
Industrial Site	3,464	1,997	₦7.15bn	₦7.1bn	45%	2.4 yr

Land use

Segment	Buildings	With generator	Spend ₦/yr	Cash saved yr 1 (B)
(Unset)	1,264,442	244,219	₦575bn	₦558bn
Farmland	1,295	225	₦390m	₦380m
Commercial	132	47	₦761m	₦731m
Industrial	101	33	₦244m	₦244m
Farmyard	8	0	₦454k	₦454k
Retail	4	0	₦74.3k	₦74.3k

Not published for this cube: Median IRR, Median payback.

Lead segment

Segment	Buildings	With generator	Spend ₦/yr	Cash saved yr 1 (B)	Median IRR	Median payback
Standard	1,227,281	222,731	₦381bn	₦365bn	25%	4.4 yr
SME High	21,888	11,823	₦92.5bn	₦92bn	37%	2.9 yr
Enterprise	16,813	9,970	₦103bn	₦102bn	43%	2.4 yr

Demand tier

Segment	Buildings	With generator	Spend ₦/yr	Cash saved yr 1 (B)
4.0	581,998	86,387	₦156bn	₦156bn
3.0	388,563	99,754	₦342bn	₦327bn
2.0	134,737	23,262	₦18bn	₦16.7bn
0.0	109,948	21,922	₦3.51bn	₦3.51bn
1.0	38,742	8,004	₦3.39bn	₦3.29bn
5.0	9,375	3,964	₦30.6bn	₦30.4bn
6.0	2,619	1,231	₦22.6bn	₦22.4bn