Projection lens

One kilowatt in London, and the range around it.

Name: Solar Analytica Projection Lens: London, Great Britain
Creator: Solar Analytica

What a kilowatt of bifacial TOPCon panels is projected to earn in London, Great Britain, as a lower, reference and upper case. The Earth baseline is frozen at its 2026-07-09 edition, and every input behind the range is pinned by hash below, so each figure can be taken apart.

Reference value: 421USD per kWp per year
Edition: 2026-09-23.1
Serving: Published snapshot
Market: GB, GB
Retail price: City 2024

All lens markets Great Britain market profile

Every figure, with the case that produced each bound.

The baseline is the unrated climatology yield before any real-world derate. The reference is an analytical planning case, not the most likely outcome, and the lower and upper bounds are named cases rather than percentiles. Money is in United States dollars.

Metric	Baseline	Lower	Reference	Upper
Specific yieldkWh per kWp per year	1,080	1,044	1,092	1,135
Energy value displacedUSD per kWp per year	416	212	421	509
Levelised cost of energyUSD per kWh	0.1535	0.1229	0.1458	0.2341
Simple paybackyears	4.7	3.6	4.2	8.7

Conditional scenario range, not a probability or confidence interval. Each bar spans a metric's lower and upper case as a percentage of that metric's own reference case, which is the zero line, so metrics in different units can share one axis. For levelised cost and payback, the lower end is the favourable one. The values behind every bar are in the table beside it. Source: Solar Analytica Projection Lens, edition 2026-09-23.1.

What each case assumes.

Retail price at its 2016 to 2024 minimum and maximum; no wholesale series for this system.

Specific yield

Lower: P90 resource year (factor 0.9558) with no constraint exposure assumed
Reference: bifacial topcon, 25-year average after degradation
Upper: bifacial topcon, year one before degradation
Baseline: unrated topcon yield from the CERES climatology, before soiling, spectral, bifacial and degradation factors

Energy value displaced

Lower: P90 resource year (factor 0.9558) with no constraint exposure assumed; retail price at its 2016 to 2024 minimum and maximum; no wholesale series for this system
Reference: reference yield at the city 2024 retail price (0.3854 USD per kWh)
Upper: bifacial topcon, year one before degradation; retail price at its 2016 to 2024 minimum and maximum; no wholesale series for this system
Baseline: unrated yield at the pinned 2024 retail price, before any real-world derate

Levelised cost of energy

Lower: 3% discount, module degradation basis, capex net of 5% subsidy
Reference: 5% discount, module degradation basis, capex net of 5% subsidy (baseline is gross capex)
Upper: 8% discount, 2% per year degradation, capex net of subsidy
Baseline: gross capex before subsidy at the 5% discount over the reference yield

Simple payback

Lower: capex net of subsidy over the upper year-one value
Reference: capex net of subsidy over year-one value at the pinned price
Upper: capex net of subsidy over the lower value
Baseline: gross capex before subsidy over the unrated-yield value

How the yield changes as the panels age.

The reference yield is an average over the asset life. This is the path it averages: the first year is highest, and each later year gives up a little to degradation. Every point is derived from the edition, not observed and not forecast.

Specific yield of one kilowatt in London in each horizon year, in kilowatt-hours per kilowatt-peak. Basis: module degradation basis: retention falls in a straight line from year one to the end of life, the same model the reference case averages; derived from the year-one yield and the life average, not observed and not forecast. The first year is the yield metric's upper case and the path averages to its reference case, so the figure and the table agree by construction. Source: Solar Analytica Projection Lens, edition 2026-09-23.1.

Year	Asset year	kWh per kWp
2027	1	1,135
2031	5	1,121
2036	10	1,103
2051	25	1,049

What this rests on.

Each input enters as a reference, a vintage and a content hash. An input this market does not have is recorded as an absence with its reason, never defaulted or borrowed from a neighbour.

Earth baseline: Sourced, vintage 2026-07-09location_yield_baseline:London, United Kingdomsha256 c1b821f81c76f965
Year-to-year resource variability: Sourced, vintage 2026-07-28market_resource_variability:London, United Kingdomsha256 e4df03903c2f22a1
Yield factors: soiling, spectrum, bifacial gain: Sourced, vintage 2026-07-09real_world_yield_stack:London, United Kingdom:topconsha256 9dd769613a22e257
Retail electricity price: Sourced, vintage 2024electricity_prices_annual:London:2024:citysha256 4029b948519e9c0c
Retail price history: Sourced, vintage 2016-2024electricity_prices_annual:London:historysha256 b4cc7a1f87dae05e
Installed capital cost: Sourced, vintage 2026-07-10capex_baseline:UKsha256 8d801769f7526da6
Subsidy: Sourced, vintage 2026-07-10subsidy_baseline:UKsha256 788208ca0af34271
Module degradation: Sourced, vintage 2026-07-10degradation_baseline:London, United Kingdomsha256 a80bd8854eb16443
Tariff edition: AbsentNo versioned retail tariff register for this market; the annual retail price row stands in.
Grid operating window: Not supplied to this editionNo grid window was supplied to this edition, so no price bound and no trigger could use one. The hash is of the empty window.sha256 ec87b0561428c100
Export constraint regime: AbsentNo reviewed export-constraint regime for this zone; no exposure is assumed.
Assumption set: Declared assumption, vintage 2026-09-22.1assumption-set:projection-lens-reference-assumptionssha256 8f01dc1e29296fd4

What would reopen it.

A crossed trigger opens a review. It never rewrites the published layer automatically. These tests were declared with the edition, as a threshold and a window a machine can evaluate.

Trigger	Window	State
Solar share of generation over the window moved by more than five points against the pinned window	90 days	Declared. Nothing to test it against yet: this edition carries no grid window.

Five layers, and where this market stands in each.

Observed record
What had happened by the evidence cut-off?
Earth baseline edition 1, verified 2026-07-09. No grid window was supplied to this edition.
Published outlooks
What did named sources say could happen?
No published outlook is joined to this lens market yet.
Scenario envelope
Which conditional planning range does the evidence support?
Each of the 4 metrics carries a baseline and a lower, reference and upper case, on TOPCon modules.
Review triggers
What new evidence would make this view worth reopening?
1 declared, 0 evaluable against a window today, 0 crossed.
Outcome and marking
What happened when the horizon became observable?
Nothing is marked yet. The first horizon year, 2027, has not ended.

What this range is, and what it is not.

The envelope is a conditional planning range under the declared assumptions. It is not a probability, a confidence interval, a forecast of returns, or a recommendation.
The reference case is an analytical planning case, not a most-likely outcome. Every bound names the case that produced it, and nothing between the bounds is weighted.
The value is what one kilowatt of panels displaces at the pinned retail price. It is not what any household, business or investor will receive, and it names no counterfactual beyond that price.
A crossed trigger opens a review. It never rewrites a published edition, and a later edition supersedes an earlier one only by declaring which input moved.
This lens publishes evidence and a conditional range for one kilowatt. It does not recommend, rank markets by desirability, assign probabilities, or constitute investment advice.

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Loading Solar Analytica

One kilowatt in London, and the range around it.

Reference value

421USD per kWp per year

Edition

2026-09-23.1

Serving

Published snapshot

Market

GB, GB

Retail price

City 2024

Metric

Baseline

Lower

Reference

Upper

Specific yieldkWh per kWp per year

1,080

1,044

1,092

1,135

Energy value displacedUSD per kWp per year

416

212

421

509

Levelised cost of energyUSD per kWh

0.1535

0.1229

0.1458

0.2341

Simple paybackyears

4.7

3.6

4.2

8.7

Year

Asset year

kWh per kWp

2027

1,135

2031

1,121

2036

1,103

2051

1,049

Trigger

Window

State

Solar share of generation over the window moved by more than five points against the pinned window

90 days

Declared. Nothing to test it against yet: this edition carries no grid window.

What this range is, and what it is not.

The envelope is a conditional planning range under the declared assumptions. It is not a probability, a confidence interval, a forecast of returns, or a recommendation.

The reference case is an analytical planning case, not a most-likely outcome. Every bound names the case that produced it, and nothing between the bounds is weighted.

The value is what one kilowatt of panels displaces at the pinned retail price. It is not what any household, business or investor will receive, and it names no counterfactual beyond that price.

A crossed trigger opens a review. It never rewrites a published edition, and a later edition supersedes an earlier one only by declaring which input moved.

This lens publishes evidence and a conditional range for one kilowatt. It does not recommend, rank markets by desirability, assign probabilities, or constitute investment advice.

Every figure, with the case that produced each bound.

What each case assumes.

Specific yield

Energy value displaced

Levelised cost of energy

Simple payback

How the yield changes as the panels age.

What this rests on.

What would reopen it.

Five layers, and where this market stands in each.

Observed record

Published outlooks

Scenario envelope

Review triggers

Outcome and marking

What this range is, and what it is not.

Every figure, with the case that produced each bound.

What each case assumes.

Specific yield

Energy value displaced

Levelised cost of energy

Simple payback

How the yield changes as the panels age.

What this rests on.

What would reopen it.

Five layers, and where this market stands in each.

Observed record

Published outlooks

Scenario envelope

Review triggers

Outcome and marking

What this range is, and what it is not.