Nigeria rooftop solar data

Rooftop solar in Gombe State: buildings, spend and payback

1,390,537 buildings in Gombe State carry a viable rooftop. Together they spend ₦209bn a year on grid power and generator fuel, and 6% of them run a generator.

Viable buildings

1,390,537

Usable roof area

45.9 km²

10.1 GWp of roof capacity

Current energy spend

₦209bn/yr

179 GWh/yr from generators

Median payback

8.9 yr

Median IRR 11% (cash saved)

The savings bracket for Gombe

Approach B

Cash saved

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

Current energy spend₦209bn/yr

Year-one cash saved₦173bn

Lifetime cash saved₦9.37tn

NPV₦1.37tn

Median IRR11%

Median payback8.9 yr

Unlocked energy179 GWh/yr

Approach A

Energy value (upper bracket)

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

Installed capacity937 MWp

Capex₦990bn

Year-one energy value₦939bn

Lifetime energy value₦44.2tn

NPV₦7.54tn

Median IRR99%

Median payback1.1 yr

Three ways to size Gombe 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: 937 MWp
Capital cost: ₦990bn
Year 1 savings: ₦939bn/yr
NPV: ₦7.54tn
Median IRR: 99%
Median payback: 1.1 yr

The odds a rooftop in Gombe State pays back quickly

Of the 1,362,168 buildings in Gombe State with a modelled payback, 29.2% pay back inside five years and 6.6% inside three.

Payback under 5 years

29.2%

Payback under 3 years

6.6%

IRR above 20%

32.2%

Under 3 years · 7%3 – 5 years · 23%5 – 7 years · 15%7 – 10 years · 11%Over 10 years · 45%

Coverage: 98% of buildings in Gombe State produced a payback figure. Buildings with no viable scenario are excluded rather than counted as zero.

How much of Gombe State's demand actually gets met

Buildings in Gombe State consume 412 GWh/yr but want 591 GWh/yr. The 30% they cannot buy is suppressed demand — load that appears the moment supply is reliable.

Met today · 70%Suppressed · 30%

Energy wanted

591 GWh/yr

Energy consumed

412 GWh/yr

Unmet demand

179 GWh/yr

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

How many rooftops in Gombe 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 1,362,168 buildings with a modelled result out of 1,390,537 in Gombe State. 596,547 clear a positive NPV.

Payback

Under 3 years89,815 (7%)

Under 5 years397,962 (29%)

Under 7 years598,248 (44%)

Under 10 years754,762 (55%)

Return (IRR)

Above 10%714,325 (51%)

Above 15%596,547 (43%)

Above 20%447,378 (32%)

Above 25%325,390 (23%)

Electricity billing bands in Gombe 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 Gombe 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	344,240	16,767	₦46.9bn	₦36.5bn	7%	14.4 yr
A	320,222	28,162	₦53.3bn	₦52.3bn	19%	5.4 yr
D	283,668	10,241	₦40.2bn	₦17.5bn	7%	15.4 yr
B	232,034	23,212	₦49.7bn	₦48.5bn	21%	5.1 yr
E	210,373	8,793	₦19.4bn	₦17.9bn	7%	15.1 yr

Load profile

Segment	Buildings	With generator	Spend ₦/yr	Cash saved yr 1 (B)	Median IRR	Median payback
Residential	1,349,547	65,705	₦132bn	₦97.4bn	9%	9.1 yr
Commercial Retail	12,944	3,738	₦983m	₦983m	35%	2.9 yr
Commercial General	10,527	4,849	₦23.6bn	₦23.2bn	39%	2.9 yr
Worship	10,045	7,986	₦2.05bn	₦2.01bn	57%	1.9 yr
Anchor	6,302	4,317	₦48.8bn	₦47.3bn	57%	1.9 yr
Industrial	865	496	₦823m	₦821m	53%	2.1 yr
Hospitality	129	29	₦887m	₦863m	37%	2.9 yr
Filling Station	113	43	₦91.2m	₦90.9m	37%	2.9 yr
Mall Retail	40	9	₦116m	₦116m	37%	2.9 yr
Productive Use	25	3	₦13.4m	₦13.4m	37%	2.9 yr

Roof size band

Segment	Buildings	With generator	Spend ₦/yr	Cash saved yr 1 (B)	Median IRR	Median payback
Under 30m2	759,207	32,509	₦5.79bn	₦5.51bn	5%	15.9 yr
30 50m2	288,239	16,215	₦14.4bn	₦7.85bn	15%	6.9 yr
50 100m2	230,408	17,713	₦31.9bn	₦19bn	27%	4.1 yr
100 250m2	94,013	14,860	₦54.1bn	₦40.2bn	31%	3.6 yr
250 1000m2	17,774	5,381	₦55.5bn	₦53.9bn	31%	3.4 yr
Over 1000m2	896	497	₦47.8bn	₦46.3bn	43%	2.4 yr

Settlement type

Segment	Buildings	With generator	Spend ₦/yr	Cash saved yr 1 (B)	Median IRR	Median payback
Unclassified	377,424	13,159	₦69.3bn	₦36.7bn	5%	16.1 yr
Urban Centre	322,204	31,939	₦62.3bn	₦61.1bn	19%	5.4 yr
Urban	294,538	18,404	₦46.1bn	₦44.1bn	9%	9.4 yr
Rural	221,846	10,283	₦12.9bn	₦12.3bn	9%	13.6 yr
Dense Urban	174,525	13,390	₦19bn	₦18.5bn	19%	5.4 yr

Building type

Segment	Buildings	With generator	Spend ₦/yr	Cash saved yr 1 (B)	Median IRR	Median payback
Shed	729,418	19,310	₦3.39bn	₦3.39bn	7%	15.6 yr
Residential Small	215,655	18,715	₦41.1bn	₦21.4bn	29%	3.6 yr
Residential Informal	188,372	11,927	₦8.61bn	₦8.61bn	17%	5.6 yr
Residential	126,436	12,858	₦77.5bn	₦62.5bn	19%	5.4 yr
Residential Formal	87,661	2,814	₦1.4bn	₦1.39bn	17%	6.1 yr
Kiosk Shop	12,942	3,739	₦979m	₦979m	35%	2.9 yr
Institutional	7,162	5,381	₦40.1bn	₦39.5bn	55%	1.9 yr
Commercial	4,210	1,511	₦11.5bn	₦11.3bn	37%	2.9 yr
Place Of Worship	3,369	2,644	₦328m	₦328m	57%	1.9 yr
Worship Center	3,345	2,660	₦498m	₦498m	59%	1.9 yr
Educational Facility	2,214	1,618	₦3.28bn	₦3.28bn	81%	1.4 yr
Commercial Corridor	1,767	459	₦4.31bn	₦4.19bn	37%	2.9 yr

Land use

Segment	Buildings	With generator	Spend ₦/yr	Cash saved yr 1 (B)
(Unset)	1,389,493	86,591	₦205bn	₦168bn
Industrial	461	413	₦4.71bn	₦4.64bn
Retail	395	0	₦5.18m	₦5.18m
Commercial	177	171	₦58.4m	₦58.4m
Farmyard	8	0	₦184k	₦184k
Farmland	3	0	₦59.2k	₦59.2k

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	1,377,343	80,387	₦144bn	₦109bn	11%	8.9 yr
Enterprise	6,966	4,723	₦49.4bn	₦47.8bn	57%	1.9 yr
SME High	6,228	2,065	₦16.3bn	₦16bn	37%	2.9 yr

Demand tier

Segment	Buildings	With generator	Spend ₦/yr	Cash saved yr 1 (B)
0.0	723,890	20,625	₦3.4bn	₦3.4bn
2.0	230,428	20,203	₦32.6bn	₦22.5bn
3.0	175,739	23,552	₦131bn	₦106bn
4.0	140,485	7,442	₦21.2bn	₦21bn
1.0	116,821	14,640	₦7.99bn	₦6.42bn
5.0	2,758	553	₦6.7bn	₦6.57bn
6.0	416	160	₦6.54bn	₦6.35bn