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17 editorial pieces · Updated 2026Editorial · 18 pieces

Insights for commercial solar finance.

Working editorial on tariffs, allowances, the macro backdrop, and the practical mechanics of structuring commercial solar projects in the UK. No vendor pieces — just working numbers and what they mean.

Featured analysis · Updated 2026

UK regional solar funds compared — every regional decarbonisation programme assessed against capital purchase economics

10 minute read · Editorial team · Most-linked piece on the site

Read the full analysis
REFERENCE DATA 14 min · 2026-05-04

UK regional solar funds compared 2026 — all 30+ programmes

Comprehensive table of UK regional commercial solar funding — combined authorities, Investment Zones, devolved-nation schemes, foundation grants, innovation funding.

STORAGE 9 min · 2026-04-30

Battery retrofit on existing commercial solar — when it works and when it doesn't

Battery retrofit on existing commercial solar — inverter compatibility, DNO consent, project economics, and the scenarios where retrofit makes sense.

TECHNICAL 11 min · 2026-04-28

A real half-hourly data analysis: how the right size moved IRR by 4 points

A working-numbers walkthrough of half-hourly demand data analysis on a Yorkshire food production site.

PUBLIC SECTOR 10 min · 2026-04-22

NHS Trust PSDS Phase 4 application strategy — bundles that win

NHS Trust PSDS Phase 4 application strategy — bundles, multi-site portfolio bids, what scoring patterns emerge in awarded bids.

TAX 9 min · 2026-04-15

FYA deadline mechanics: year-end planning for the 31 March 2026 cliff

Practical year-end planning for capturing the 50% First Year Allowance before the 31 March 2026 deadline.

TAX 8 min · 2026-04-12

The 2026 Budget and the 50% FYA: what changed and what it means for commercial solar

The 50% FYA extension to 31 March 2026 is the most consequential single line for commercial solar economics.

TECHNICAL 8 min · 2026-04-08

Solar carport economics in 2026 — when the second-storey roof is worth it

Commercial solar carport economics in 2026. Capex premium versus rooftop, EV charging integration, scenarios where carports beat rooftop.

TECHNICAL 9 min · 2026-03-30

Solar export limits in the UK 2026 — when the DNO becomes the binding constraint

UK DNO export consents are increasingly the binding constraint on commercial solar sizing — particularly on industrial estates with limited grid headroom.

METHODOLOGY 10 min · 2026-03-25

After-tax IRR modelling: what installer brochures get wrong

Installer brochures routinely quote 25-year IRRs of 25–35%. Our modelling on the same projects produces 14–20%.

TARIFFS 11 min · 2026-03-18

Where commercial electricity tariffs are heading in 2026

Wholesale, network charging, and policy costs decomposed for 2026 commercial electricity tariffs.

TAX 9 min · 2026-03-12

AIA vs FYA detailed comparison — when each wins for commercial solar

Detailed comparison of Annual Investment Allowance vs 50% First Year Allowance for UK commercial solar with worked numbers.

DECISION FRAMEWORK 8 min · 2026-03-08

Capex vs PPA: a decision tree for commercial solar in 2026

A structured decision framework for choosing between capital purchase and Power Purchase Agreement.

PUBLIC SECTOR 9 min · 2026-02-26

PSDS Phase 4: what we're seeing in the application pipeline

Working notes from the PSDS Phase 4 application window: cost-per-tonne thresholds, common scoring failures.

PROPERTY 9 min · 2026-02-18

MEES-driven commercial solar — refurbishment windfall in 2026

How the Minimum Energy Efficiency Standards (MEES) framework drives commercial property solar deployment.

STORAGE 12 min · 2026-02-05

When battery storage actually changes the solar finance case

Battery economics for commercial solar in 2026: time-of-use exposure, export-limit relief, capacity market access.

PROPERTY 10 min · 2026-01-22

The landlord-tenant solar split: structures that actually work

Three workable solutions to the landlord-tenant capex/benefit split for commercial solar.

TECHNICAL 9 min · 2025-12-14

Why half-hourly demand data changes the system size answer

Designing commercial solar by half-hourly demand profile rather than headline annual consumption.

EXPORT TARIFFS 7 min · 2025-11-30

Smart Export Guarantee tariffs Q1 2026: a cross-supplier comparison

Smart Export Guarantee tariff comparison across the major UK licensed suppliers in Q1 2026.

Frequently asked questions

What topics does the Commercial Solar Finance insights section cover?
The insights section covers technical and financial topics that affect commercial solar investment decisions: half-hourly demand data and system sizing, electricity tariff trends, the 50% First Year Allowance and its interactions with different finance structures, MEES regulations and EPC improvement, Smart Export Guarantee tariff analysis, PSDS grant application strategy, battery storage economics, landlord-tenant solar structures, DNO export limits, and after-tax IRR modelling. Articles are updated when regulations or market conditions change significantly.
How does the FYA interact with different commercial solar finance structures?
The 50% First Year Allowance is only available to the asset owner. Under capital purchase or hire purchase (asset finance), the customer owns the asset and claims the FYA. Under a green loan, the customer owns the asset and claims the FYA (the loan is a liability, not an ownership structure). Under operating lease or PPA, the lessor/PPA provider owns the asset and claims the FYA — the customer cannot. This difference in FYA access is the primary financial reason profitable owner-occupiers with taxable profits prefer capital purchase or loan over lease for commercial solar.
What is the current UK grid carbon intensity and why does it matter for solar?
The UK grid carbon intensity in 2026 is approximately 0.233 kgCO2 per kWh — lower than pre-2020 levels due to the continued expansion of offshore wind and the retirement of coal generation. For solar investment, grid carbon intensity determines the CO2 abatement value of each kWh generated and the strength of the net-zero business case. For grant applications like PSDS, carbon intensity is used directly to calculate cost-per-tonne-abated metrics. For Scope 2 reporting, businesses using the "location-based" method use the grid average; those using "market-based" methods use supplier-specific or renewable energy certificate rates.
How often are the commercial solar finance insights articles updated?
Articles covering market-sensitive data — electricity tariff trends, SEG rates, PSDS application guidance, FYA and AIA limits — are reviewed and updated quarterly or when significant regulatory changes occur. Technical articles on solar sizing, finance structures, and IRR modelling are updated annually. Each article displays a publication date and is marked when substantive revisions have been made. Readers are encouraged to verify regulatory and tariff data independently before making financial decisions, as market conditions can change faster than the publication cycle.

Commercial solar finance insights: analysis and commentary

Our insights section provides in-depth analysis of commercial solar finance trends, policy changes, and market developments. Written for finance directors, energy managers, and sustainability leads, these articles go beyond headline news to examine what policy and market changes mean for your solar investment decision.

Featured insights

AIA vs 50% FYA: detailed comparison for 2026

Analysis of when Annual Investment Allowance and 50% First Year Allowance each apply, with worked examples for systems ranging from 100kWp (£88,000) to 2MWp (£1.5m). Covers the £1m AIA threshold, group company AIA sharing, and strategies for maximising first-year tax relief on large installations.

Battery retrofit for existing solar installations 2026

Analysis of the economics of adding battery storage to existing commercial solar installations, including half-hourly demand modelling, SEG arbitrage opportunities with Octopus Agile, demand response revenue, and asset finance options for battery additions. Case studies from logistics, manufacturing, and NHS sites.

NHS PSDS Phase 4 application strategy

Detailed analysis of NHS Trust PSDS Phase 4 application criteria, scoring methodology, and application strategy. Covers how to structure combined solar + heat pump projects for maximum grant award, common application weaknesses, and how NHSE support teams can assist.

Commercial solar carports: economics in 2026

Comprehensive analysis of solar car park canopy economics — construction costs per kW, shading profiles, EV charging integration revenue, planning requirements, and finance structures for car park solar projects. Includes comparison of steel vs membrane canopy structures.

CapEx vs PPA decision tree

A structured decision framework for commercial solar finance selection, incorporating credit profile, lease/ownership status, tax position, AIA benefit, cash availability, and long-term strategic goals. Interactive tool with worked examples for common business scenarios.

Recent policy and market developments

AIA permanent confirmation

HMRC confirmed the £1m Annual Investment Allowance is now permanent (previously subject to annual reconfirmation). This removes the timing risk that previously encouraged businesses to rush installations before year-end to secure AIA. Businesses can now commit to solar on their own schedule without AIA cliff-edge concerns.

PSDS Phase 4 funding committed

The government committed £1.425 billion to PSDS Phase 3e and beyond through to 2028. This multi-year commitment improves planning certainty for public sector bodies considering large decarbonisation programmes. SALIX application windows are expected to open bi-annually through 2027.

SEG market competition increasing

The Smart Export Guarantee market has matured with increasing competition between suppliers. Octopus Agile export now pays average 6–12p/kWh vs the 3p/kWh floor from most suppliers. For commercial solar owners with battery storage, smart SEG selection adds meaningful income over 20-year system life.

Staying current with commercial solar finance

The commercial solar finance landscape evolves continuously — driven by Bank of England rate decisions (affecting green loan pricing), government spending reviews (affecting PSDS funding), HMRC Capital Allowances guidance updates, and SEG market competition. Our insights are updated regularly to reflect these changes.

For personalised advice on how current market conditions affect your specific solar project, contact our specialist commercial solar finance team for a no-obligation consultation.

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