Residential solar value · July 2026

The sunniest market is not the fastest solar payback.

A residential-solar value model splits three questions that are often blended together: where a rooftop produces most, where solar electricity is cheapest to generate, and where a household recovers installed cost fastest. On the frozen 40-market snapshot, those are different places. A wider 64-location leaderboard adds 24 resource-benchmark sites and a second champion, one that comes with a caveat the first does not.

The split

Resource, generation cost and household payback point to different markets.

Solar resource alone does not decide household value. Alice Springs is the modelled gross and net payback champion because strong yield meets low installed cost and Australian retail electricity prices. Lhasa is the modelled LCOE champion because high yield meets low capex, but lower retail electricity value pushes its simple payback to 4.8 years. Cairo sits near the top on yield and near the bottom on payback because the modelled residential retail price is only US$0.023/kWh.

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Three axes · frozen snapshot

The leader changes with the question

Alice Springs gross payback2.2 yr

fastest gross

Lhasa payback4.8 yr

lowest LCOE

Cairo payback22.2 yr

high yield, low tariff

Chart data

Series	Value	Note
Alice Springs gross payback	2.2 yr	fastest gross
Lhasa payback	4.8 yr	lowest LCOE
Cairo payback	22.2 yr	high yield, low tariff

Axis	Market	Modelled result	Why it leads
Fastest gross payback	Alice Springs, Australia	2.2 years	High yield, US$1,000/kWp gross capex, US$0.227/kWh retail price
Fastest net payback	Alice Springs, Australia	1.7 years	20% STC incentive applied to the gross capex baseline
Lowest LCOE	Lhasa, China	US$0.032/kWh	High yield and US$700/kWp capex, despite lower retail value
Largest HJT-over-PERC edge	Dubai, UAE	+14.2% by year 25	Harsh climate conditions amplify the modelled technology advantage
Yield object lesson	Cairo, Egypt	22.2-year payback	Third-ranked yield, but subsidised retail electricity at US$0.023/kWh

All payback, LCOE, yield-stack and HJT-over-PERC values are modelled, not measured household bills. The table reports the frozen v1 snapshot, reference date 2026-07-10.

The wider geography

A second geography, 24 new sites, one gap still open.

The frozen 40-market leaderboard above is one geography: cities with a direct CERES yield measurement. A second, wider leaderboard adds 24 resource-benchmark sites, desert and outback locations chosen for solar resource rather than population, with yield calibrated to the same CERES scale (it reproduces the 40 markets’ own yields to within about 2.6% RMS). Combined, the unified leaderboard covers 64 locations. The benchmark sites carry the same bifacial gain, spectral response and degradation layers as the market cities. What they don’t have yet is soiling, so their payback and LCOE run slightly better than a fully modelled result would show.

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Unified 64-location leaderboard · frozen 2026-07-10

The overall champion carries a caveat the runner-up market does not

Calama, Chile (benchmark)2.0 yr*

no soiling layer

Pilbara, Australia (benchmark)2.1 yr*

no soiling layer

Alice Springs, Australia (market)2.2 yr

verified, no caveat

Chart data

Series	Value	Note
Calama, Chile (benchmark)	2.0 yr*	no soiling layer
Pilbara, Australia (benchmark)	2.1 yr*	no soiling layer
Alice Springs, Australia (market)	2.2 yr	verified, no caveat

Rank	Location	Geography	Gross payback	Net payback	LCOE
1	Calama (Atacama Plateau), Chile	Benchmark*	2.0 yr	1.4 yr	US$0.040/kWh
2	Pilbara Region, Australia	Benchmark*	2.1 yr	1.7 yr	US$0.043/kWh
3	Alice Springs, Australia	Market	2.2 yr	1.7 yr	US$0.044/kWh
3	Geraldton, Australia	Benchmark*	2.2 yr	1.8 yr	US$0.045/kWh
5	Darwin, Australia	Benchmark*	2.5 yr	2.0 yr	US$0.052/kWh
6	Perth, Australia	Market	2.6 yr	2.1 yr	US$0.049/kWh

*Benchmark rows exclude the soiling derate; see the publish note above. Market rows carry the full yield stack, including soiling, on the same basis as the frozen 40-market table. Source: unified_champion_leaderboard, reference date 2026-07-10.

The split holds inside the new geography too, more sharply than in the original 40 markets. Take Cairo/Benban Zone, Egypt: a benchmark site in the country’s main solar development zone (a different location from the Cairo city market row above). It ranks second globally on 25-year yield, at 2,168 kWh/kWp, behind only Calama. Its modelled payback is still 19.0 years, because the same subsidised US$0.023/kWh retail price that punishes Cairo city in the market table applies here too. Resource and reward keep pointing in different directions; the wider geography just gives the gap more room to show.

Gross leaderboard

Australia leads the payback table, then Chile.

The gross ranking is deliberately pre-subsidy, so markets can be compared before local incentive design changes the result. On that basis, Australia holds three of the first five rows: Alice Springs, Perth and Sydney. Chile follows with Antofagasta and Santiago. Net payback changes the order but not the headline champion: Alice Springs remains first after the modelled STC reduction.

Gross rank	Market	Country	Gross payback	Net payback	LCOE	Capex confidence
1	Alice Springs	Australia	2.2 yr	1.7 yr	US$0.044/kWh	High
2	Perth	Australia	2.6 yr	2.1 yr	US$0.049/kWh	High
3	Antofagasta (Atacama)	Chile	2.7 yr	1.9 yr	US$0.055/kWh	Medium
4	Santiago	Chile	2.8 yr	1.9 yr	US$0.056/kWh	Medium
4	Sydney	Australia	2.8 yr	2.2 yr	US$0.059/kWh	High
6	Seville	Spain	3.1 yr	2.7 yr	US$0.084/kWh	Medium
7	Berlin	Germany	3.2 yr	2.6 yr	US$0.123/kWh	Medium
7	Madrid	Spain	3.2 yr	2.7 yr	US$0.084/kWh	Medium
9	Athens (Attica)	Greece	3.3 yr	3.3 yr	US$0.076/kWh	Medium
10	Sao Paulo	Brazil	3.4 yr	2.9 yr	US$0.050/kWh	Medium

Subsidy status

Net value depends on whether a programme is current, not just whether it exists.

The Greece correction is the working rule. A sourced 75% subsidy briefly made Athens the net-payback champion, then direct verification showed the application window had closed on 2024-05-15. In the frozen record, Athens carries 0% subsidy and a 3.3-year net payback. South Africa shows the same pattern: Section 6C is present in the record as an expired programme, not an active reduction.

Three other policy facts matter in this edition. The US federal 25D Residential Clean Energy Credit is modelled at 0% because the snapshot records it as expired on 2025-12-31. China carries 0% because the national residential rooftop FIT is phased out. France retains a reduced-VAT mechanism but not the abolished self-consumption prime.

What the model includes

The value surface is a synthesis layer, not a measured bill sample.

The source chain is: energy mix, location-yield baseline and production-climate parts 01/05-11 into real_world_yield_stack, then 2025 retail electricity prices, per-country capex and subsidy baselines into solar_value_surface, then the frozen champion_leaderboard_v1_2026_07_10. The yield stack includes soiling, spectral response, bifacial gain and degradation. Temperature is already in the CERES baseline. Smoke and storm events are excluded from annual yield because they are episodic.

The 24 benchmark-only sites in the wider leaderboard use a different yield method: NASA POWER irradiance and temperature run through a yield-factor fit calibrated against the 40 CERES-direct markets, reproducing their yields to about 2.6% RMS (the underlying GHI values agree to about 1.6%). They carry the same bifacial, spectral and degradation layers as the market cities. Soiling is the one layer not yet extended to them, which is why every benchmark row carries a caveat in unified_champion_leaderboard.

Confidence flags stay attached to the figures. CAPEX confidence is High only for the US, Australia and India among the original 40 markets; several sparse markets are Low. The new benchmark sites vary more: Australian sites inherit the High confidence already established for that market, while sparser sites such as Peru sit at Low. Soiling is a no-cleaning worst case on the 40 markets, with 17 unquantified, and absent entirely on the 24 benchmark sites. Five markets have only 2025 price coverage. Albedo is a conservative lower bound. These flags are not footnotes after the fact: they are part of the result.

Sourcesdatabase snapshot and method comments

• Supabase project lbbusysvdoiqyvieieyh, frozen table champion_leaderboard_v1_2026_07_10, reference date 2026-07-10, edition v1.
• Object comments read for real_world_yield_stack, solar_value_surface, champion_leaderboard, capex_baseline, subsidy_baseline and electricity_prices_annual.
• Model literature named in the handoff: bifacial model Sun et al. 2018; spectral response Lee & Panchula 2016 and Dirnberger 2015; degradation Jordan & Kurtz 2013.
• 2026-07-11 update: added the unified 64-location leaderboard (40 markets + 24 resource-benchmark sites) from the Solar Analytica v2 data hand-off (2026-07-10). Object comments read for unified_value_surface and unified_champion_leaderboard; figures queried live from the database, not the hand-off document itself.