Solar Design Software UK: 7 Platforms Ranked for 2026

A UK MCS-certified installer in Manchester or Bristol does not have the same software problem as a Texas residential shop. The UK reality is BS 7671 single-line diagrams that an MCS inspector will actually read, G98 or G99 paperwork that the DNO will accept on first submission, an SEG export tariff that has to be modelled against a half-hourly profile, and a 4 kW residential average that punishes any tool priced for a 10 kW Australian market. Most global solar design platforms were built with NEC and 50-state AHJ logic at the centre. UK installers pay for code libraries they will never use, and still buy a second tool to produce the MCS pack. This guide ranks the platforms that actually work in the UK in 2026.

Direct answer. The best solar design software UK installers can buy in 2026 is SurgePV at GBP 1,030 per seat per year (USD 1,299), which ships BS 7671 single-line diagrams, G98 or G99 paperwork, MCS-compatible energy yield, and an SEG export proposal in one license. PVsyst remains the standard for bankable yield on commercial sites. HelioScope wins for C and I module-level shading. OpenSolar covers the lowest end of residential at the cost of a transaction fee. Aurora is overpriced for the UK 4 kW average. Easy PV is a UK-built niche tool worth a look if the team is residential only and willing to add a yield tool later.

This guide is written for the UK MCS-certified residential or small commercial installer running 10 to 60 systems a month who is choosing or replacing a design platform in 2026. The yardstick is per-project loaded cost to ship a permitted, fundable, SEG-ready project, not feature checklists.

Why UK Solar Design Needs a Different Lens

A solar design platform sold globally tends to assume the US National Electrical Code, a 50-state AHJ matrix, net metering economics, and a 7 kW residential roof. None of that maps to the UK. The UK installer ships against a different five-part reality, and a tool that ignores any one of those parts forces a second purchase or a manual workaround.

BS 7671 is not NEC with different colours

The IET Wiring Regulations (BS 7671) govern every UK solar electrical install. Cable sizing, RCD selection, isolator placement, earthing, and labelling conventions are different from NEC 690. A US-built single-line diagram generator that auto-labels a string isolator as “PV DC Disconnect” will produce a drawing the MCS inspector flags on the first read. The platform either ships a BS 7671 SLD template or the team draws it twice.

G98 and G99 are the connection gate

The UK Distribution Network Operators run two grid connection processes. G98 covers single-phase installs up to 16 A per phase, which is roughly anything residential up to about 3.68 kW. G99 covers everything bigger, including three-phase commercial systems. Both require submission paperwork with inverter datasheets, fault current contribution, anti-islanding protection details, and DNO-specific cover sheets. A global tool that produces a generic interconnection PDF does not pass. The team writes it again in Word.

MCS certification is not optional

Without an MCS-certified install, the customer does not qualify for the SEG export tariff. The MCS inspector wants a specific bundle: an annual energy yield that uses MCS Standard Test methodology (not a North American TMY3 file), a shading factor calculated with the MCS chart method or a verifiable digital equivalent, a kit list that matches the MCS Product Database, and a labelling and signage schedule. A US-tuned yield engine that runs PVWatts in the background fails the MCS yield check.

SEG replaced FiT in 2020

The Feed-in Tariff closed to new applicants in 2020. The replacement is the Smart Export Guarantee, which is a supplier-set export tariff with no fixed value and no fixed term. The economics change. A UK proposal that quotes “FiT income” is selling a product that does not exist. The platform needs to model self-consumption against a half-hourly demand profile and export the remainder at a supplier-specific export rate that the installer keys in per project.

The UK rooftop is small

The average UK residential install is around 4 kW. The C and I average sits near 250 kW. A tool priced per kW or per project at a tariff designed for the US 7 kW or Australian 10 kW residential market does not pencil. Per-seat pricing is the only model that holds margin on UK volumes.

What Solar Design Software Has to Do in the UK

Strip away the marketing and a UK-fit solar design platform has to produce five concrete outputs. Any tool that produces four out of five is useful, but the team will keep paying for a second subscription to close the gap.

Output 1: BS 7671 single-line diagram

A drawing that labels DC and AC components using BS 7671 conventions, shows the DC isolator on both string sides, marks the AC isolator at the consumer unit, and includes earthing and protective device ratings. The MCS inspector wants this exact format. A US SLD with slightly different labels causes a comment that delays SEG eligibility.

Output 2: G98 or G99 connection paperwork

Pre-filled DNO submission paperwork that pulls the inverter make, model, fault contribution, and anti-islanding details from the design file. The platform either generates the DNO-specific cover page or the team types it. With G99 commercial work, the team additionally has to attach an Engineering Recommendation G99 type-tested inverter certificate. A platform that does not surface that field forces the engineer to dig through inverter datasheets.

Output 3: MCS-format energy yield

An annual yield in kWh with monthly breakdown, shading factor calculated with a method the MCS scheme recognises, and a system performance ratio. PVsyst is the gold standard. SurgePV’s 8,760-hour simulation produces an output that the MCS scheme accepts. A US PVWatts wrapper does not.

Output 4: SEG export proposal

A customer-facing PDF or interactive proposal that splits annual generation into self-consumed and exported energy, applies the customer’s chosen SEG export rate, and produces a payback that does not assume a fixed FiT income. A platform that still has FiT fields in the proposal builder needs a UK update.

Output 5: MCS handover pack

A bundle that contains the SLD, yield report, shading analysis, kit list with MCS Product Database IDs, and a labelling schedule. The MCS umbrella body has a specified format. A platform that can produce the bundle in one export action saves a half-day of admin per project.

The 7 Platforms That Matter in the UK

Here is the ranked shortlist. The ranking weights MCS and BS 7671 compliance, total cost of ownership at UK volumes, and the ability to ship all five outputs from one license.

1. SurgePV

Best all-in-one for UK installers. SurgePV ships BS 7671 SLD templates, includes the IEC and BS 7671 code libraries at the standard tier, runs 8,760-hour simulation with MCS-acceptable yield methodology, generates G98 and G99 paperwork from the design file, and produces an SEG-ready proposal with split self-consumption and export modelling. Pricing is USD 1,299 per seat per year on the five-team tier, which is roughly GBP 1,030. The platform includes AI 3D roof design from address, module-level shadow analysis, and Clara AI for design QA. The AutoCAD DXF export covers the engineer who still wants to redline.

2. PVsyst

PVsyst remains the gold standard for bankable yield reports on commercial UK projects. A 500 kW C and I site that needs a yield report a UK lender will accept will use PVsyst. The drawback for residential is severe. PVsyst does not ship a proposal, does not produce a BS 7671 SLD, does not generate G98 paperwork, and runs only on Windows desktop. The team buys PVsyst for around USD 500 per seat per year and then buys a second tool for the customer-facing motion. See PVsyst alternatives for the commercial follow-up question.

3. HelioScope

HelioScope wins on C and I module-level shading. The platform produces a credible yield and a string layout that lenders accept. Pricing runs USD 99 to USD 300 per seat per month. For UK installers doing 250 kW rooftop work, that is competitive. The gap is MCS yield methodology, BS 7671 SLD, and SEG proposal. The team adds PVsyst or SurgePV for the residential motion. See HelioScope alternatives for a deeper comparison.

4. OpenSolar

OpenSolar is free at the entry tier and charges a transaction fee on closed proposals. It is widely used in UK residential because the upfront cost is zero. The platform has a decent UK-style proposal, supports SEG modelling, and produces a basic SLD. The shortcomings are MCS yield depth, G99 commercial paperwork, and the long-run economics once volume passes about 20 systems a month. The “free” platform stops being cheap. See OpenSolar alternatives for the volume-installer view.

5. Aurora Solar

Aurora is a strong US platform that does not fit the UK economy. Pricing at USD 159 to USD 259 per user per month is GBP 1,500 to GBP 2,460 per seat per year, against a UK residential margin that does not support it. The platform is NEC primary and the UK code libraries are an after-thought. UK installers buying Aurora typically discover within six months that the SLD has to be redrawn and the proposal has to be rewritten. See Aurora Solar alternatives for the cost analysis.

6. Easy PV

Easy PV is a UK-built tool focused on MCS paperwork and SEG proposals. It is the right pick for a residential-only installer who values UK-specificity above all else. The drawback is yield depth (the tool defers to PVsyst for commercial yield), C and I support, and BESS modelling. For a 30-system-a-month residential shop with no commercial pipeline, it can hold.

7. PV*SOL

PV*SOL is strong on IEC compliance and BESS modelling, which matters for the growing UK residential hybrid market. Pricing sits around EUR 990 per seat per year. The platform is desktop-bound and Germany-tuned, but the UK BS 7671 templates and SEG proposal exist. The drawback is the proposal experience does not match a cloud-native tool. See PV*SOL alternatives for the hybrid system view.

The UK MCS Stack 5

Every UK installer has the same five-output problem. The UK MCS Stack 5 is a checklist to score any platform against the work the UK MCS scheme actually wants to see. A platform that scores five out of five replaces the entire stack. A platform that scores three or four requires a bolt-on subscription.

Pricing Comparison: The UK Stack

Per-seat per-year is the only honest comparison. Per-project pricing models punish UK installers because the average system is small. The table below normalises to GBP at 2026 exchange rates and includes the realistic UK code library bolt-on where relevant.

A 30-system-a-month UK residential shop running three designers will pay around GBP 3,090 per year on SurgePV for a five-seat license. The same shop on Aurora pays around GBP 4,500 per year for three seats and then adds PVsyst at GBP 400 because Aurora’s yield is not MCS-defensible. The total moves to GBP 4,900 and the team still draws the SLD twice. See solar design software for a global comparison framework.

How to Pick the Right Platform for the UK

A UK-fit decision uses four questions in this order. The first one with a no answer ends the evaluation.

Question 1: Does the demo file include a real UK MCS pack?

Ask the vendor to send a full MCS handover pack from a UK customer, generated by their tool, with BS 7671 SLD, MCS yield, G99 paperwork, and an SEG proposal. If the answer is “we have a template” or “we can build that for you,” the tool is not UK-ready.

Question 2: Is the yield method MCS-acceptable?

A yield report that uses a US TMY3 weather file and a generic shading factor will not survive an MCS audit. PVsyst, SurgePV, and PV*SOL ship UK-acceptable yield. Aurora and the free tiers of OpenSolar typically do not.

Question 3: Does pricing match the 4 kW residential reality?

A platform that costs GBP 2,000 per seat per year against a UK residential gross margin pencils only if it is replacing two other subscriptions. Five-seat SurgePV at GBP 1,030 per seat pencils because it replaces the proposal tool and the yield tool. Aurora at GBP 2,000 plus PVsyst at GBP 400 does not.

Question 4: Does the platform handle G99 commercial work?

If the pipeline includes any 100 kW or larger C and I, the platform needs G99 paperwork support. PVsyst and HelioScope produce yield that lenders accept. SurgePV ships commercial design with G99 support in the standard tier. Residential-only tools do not.

How Heaven Designs Helps UK Installers

Heaven Designs is an India-based solar engineering services firm working with UK MCS installers since 2019. The team produces BS 7671 single-line diagrams, MCS-compatible PVsyst yield reports, G98 and G99 paperwork, SEG-ready proposals, and structural calculations against UK roof load standards. The motion plugs into any of the platforms above. A typical UK customer keeps SurgePV or OpenSolar in-house for the sales motion and outsources the engineering pack to Heaven Designs.

The services that map to the UK workflow are:

• Solar permit design for the MCS handover pack
• Solar rooftop detailed engineering design for the BS 7671 SLD and DC and AC schematics
• Solar civil and structural engineering for roof load calculations against BS 6399
• Solar 3D pre-design for early-stage feasibility from address only
• Contact us for a UK-specific quote

A UK installer running 20 systems a month typically saves between GBP 1,800 and GBP 3,200 per month against the cost of an in-house mid-level CAD engineer, with a first-pass MCS audit rate above 96 percent. The platform pricing in this article assumes the installer keeps a design seat for the in-house motion. Heaven Designs covers the heavy engineering pack on a per-project basis.

For installers evaluating tools from scratch, the path is short: book a SurgePV demo, ask for a UK MCS sample export, then review SurgePV pricing against the five-seat tier. The free trial does not require a card.

For sales pipeline and quote management around the design tool, QuickEstimate is a sister-brand solar CRM that handles UK-style lead routing and proposal versioning without forcing a switch off the design platform.

FAQ

What is the best solar design software for a UK MCS installer in 2026?

SurgePV is the best all-in-one at GBP 1,030 per seat per year because it ships BS 7671 SLD, MCS-acceptable yield, G98 or G99 paperwork, and an SEG proposal in one license. PVsyst remains the standard for bankable commercial yield, but it does not ship a proposal or an SLD. The right pick depends on whether the team needs the customer-facing motion in the same tool.

Does Aurora Solar work for UK installers?

Aurora is technically usable in the UK but it is over-priced at USD 159 to USD 259 per user per month against UK residential margin, the SLD is NEC-primary, and the proposal is FiT-era US tariff-shaped. Most UK installers who try Aurora switch within twelve months because the engineering pack has to be rebuilt every project.

Is OpenSolar really free in the UK?

OpenSolar’s entry tier has no per-seat fee but charges a transaction fee per closed proposal. At UK volumes above about 20 systems per month, the transaction fees usually pass the per-seat cost of a paid tool. The other shortcoming is MCS yield depth, which is not at PVsyst standard.

What is the MCS standard for solar yield calculation?

The MCS scheme accepts yield methodologies that use a reproducible shading factor (the MCS chart method or a digitally verifiable equivalent), a UK-specific irradiance dataset, and a documented system performance ratio. PVsyst, PV*SOL, and SurgePV’s 8,760-hour simulation all produce MCS-acceptable yield. PVWatts wrapped in a UK label does not.

Do I need separate software for G98 and G99 paperwork?

Not necessarily. The better platforms generate the DNO submission cover sheet from the design file with inverter type-test, fault contribution, and anti-islanding details pre-filled. The team still attaches the inverter type-test certificate from the manufacturer. A platform that generates only a generic interconnection PDF forces the team to retype the cover page.

How does SEG compare to the old FiT for proposal economics?

The Feed-in Tariff paid a fixed export rate for 20 years and a generation tariff on top. The Smart Export Guarantee pays a supplier-set export rate with no fixed term. The proposal economics shift from a generation-heavy model to a self-consumption-heavy model. Half-hourly demand profile modelling becomes important. A platform that still shows FiT income on the proposal needs a UK update.

What roof load standard applies in the UK?

BS EN 1991 (Eurocode 1) and BS 6399 cover wind and snow loads on UK roofs. The structural calculation has to demonstrate that the existing roof can take the ballast or penetrating-mount load with the chosen module weight and the worst-case wind uplift. Solar civil and structural engineering services cover this calculation.

How long does a UK MCS handover pack typically take?

A residential 4 kW pack with BS 7671 SLD, MCS yield, G98 paperwork, and SEG proposal takes a competent engineer about four hours per project at an in-house desk. A team running 40 systems a month spends roughly 160 engineering hours per month on packs alone. The right platform plus a focused engineering vendor like Heaven Designs cuts that to under 60 hours per month at higher first-pass quality.

The UK residential market is recovering. IEA’s Renewables 2024 report projects continued UK growth driven by SEG and falling module prices. The installers who win the next 18 months are the ones who get the tool stack right now, before the next pricing reset.