Solar glossary
Latent demand: what it means and why it matters
The energy a building would use if power were always available — not the energy it actually consumes today.
Why it matters in Nigeria
Nigerian consumption is suppressed by outages and fuel cost. Sizing to latent demand shows what a rooftop could serve; valuing savings against latent demand would overstate cash saved, which is why the two are kept apart.
How PureWatts measures it
Total Latent demand
sum_latent_demand_kwh_yr
Sum over the buildings in the group. Latent demand.
Sum over the buildings in the group.
Total Served
sum_served_kwh_yr
Sum over the buildings in the group. Energy actually consumed today.
Sum over the buildings in the group.
Total Unlocked (Merit-order sized)
sum_sc3_unlocked_kwh_yr
Sum over the buildings in the group. Suppressed demand the system lets the building start consuming — energy it wants but cannot currently get or afford.
Solar + battery, merit-order sized: Same engine as sc2, but the target is what the building CONSUMES today x 1.5 (MO_SIZING_UPLIFT) rather than full latent demand.
In Osun, sizing sc2 to latent demand while crediting it only with displacing current spend produced a 6x-oversized system and a negative IRR that said nothing about solar. sc3 is the fix, not an alternative opinion.
Sum over the buildings in the group.
See these numbers for your area
Every state and local government area page reports latent demand for its own rooftops. Browse the Nigeria rooftop solar data.
Related terms
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.