Fronius is the second-most installed commercial inverter brand in the UK after SolarEdge, with strong market position in the 30 kW to 200 kW segment and dominant share in agricultural and rural commercial sites where their Tauro and Symo three-phase platforms have been the workhorse for over a decade. Every Fronius inverter sold since 2013 ships with built-in monitoring through Solar.web — the company's free web and mobile platform that provides live and historical generation data, alerts, reporting, and (with the optional Smart Meter add-on) full energy-balance monitoring including self-consumption and export. This guide covers Solar.web setup, the dashboards you actually use, how alerts work, the Premium tier value, multi-site portfolio management for installers and large commercial customers, and how Solar.web compares to SolarEdge MySolarEdge.
Solar.web platform overview
Fronius Solar.web is a web and mobile platform (iOS and Android) for monitoring all Fronius inverters since 2013. The architecture: every Fronius inverter has a DataManager card built into the unit (DataManager 2.0 on current inverters, earlier DataManager 1.0 on units pre-2017). The DataManager pushes generation data to the Fronius cloud over Ethernet, Wi-Fi, or cellular at 1-minute resolution. The cloud aggregates and serves the data via solarweb.com (web dashboard) and the Solar.web Live mobile app. Account ownership transfers from the installer to the site owner at commissioning handover.
Two account tiers: Solar.web LIVE is free for the lifetime of the inverter and covers most commercial use cases. Solar.web Premium (~£3-5 per inverter per year) adds extended historical resolution, multi-site portfolio dashboards, professional report templates, and the PR (Performance Ratio) and specific-yield KPIs needed for warranty validation and finance covenant reporting.
What you can monitor
Current and historical generation. Today's kWh, this month, this year, lifetime, all visible on the headline dashboard. Historical view drills down to 5-minute resolution for the past 12 months in LIVE tier, lifetime in Premium.
Self-consumption ratio (with Smart Meter). When the Fronius Smart Meter is installed in your AC distribution board, Solar.web shows the full energy balance: PV generation kWh, building consumption kWh, grid export kWh, grid import kWh, and the calculated self-consumption percentage (the share of PV generation used onsite versus exported). The energy balance view is the single most useful page on Solar.web for commercial customers — it tells you in 30 seconds whether your system is doing what it should.
Grid feed-in. When the Smart Meter is present, the export view shows half-hourly export to grid — the data you reconcile against your SEG supplier's billing. See /seg-tariff-comparison/ for SEG context.
Energy balance views. Hour, day, week, month, year, lifetime aggregations of generation versus consumption versus export — all selectable from the Energy Balance tab.
System alerts. Notification settings configurable in the Alerts tab, covering production loss, communication failure, and inverter hardware fault codes.
Alerts and notifications
Three alert categories matter for commercial sites:
Production loss. Fires when daily generation falls below an expected threshold compared to the modelled value. Defaults are conservative — most commercial sites tune to 65 to 75 percent of expected before alerting. Catches widespread soiling, tripped MCB, complete inverter offline.
Communication failure. Inverter has stopped uploading data. Common false-alarm trigger if not delayed by 4-6 hours. Most commercial customers configure a delay before email notification.
Hardware fault. Inverter reports a fault code — over-voltage, over-temperature, isolation fault, internal hardware error. These are real and actionable; most resolve within minutes for the soft faults (temperature derating) but persistent codes need an installer site visit.
Notification routes: email, SMS (premium add-on), and push notifications via the Solar.web Live mobile app. Multi-recipient routing is supported — one alert can fan out to facilities manager, installer, and on-call engineer simultaneously.
Data export and reporting
Solar.web supports CSV export of generation data at any selected resolution and time period. Common use cases:
Monthly summary CSV. Generation totals per day for any month, exported in 5 seconds for inclusion in management reports or ESG submissions.
15-minute or 5-minute granularity. Detailed data for any window, used for SEG income verification or warranty claim support.
PDF reports (Premium). Auto-generated monthly performance report including KPIs (Performance Ratio, specific yield, availability), exportable to PDF. The PR figure is the headline metric used in DSCR-financed installs and large commercial O&M contracts.
API access. Solar.web exposes a REST API for third-party integration. Available with Solar.web Premium. Common integrations: BI dashboards (Power BI, Tableau), facility management systems, and multi-vendor monitoring aggregators like Solytic.
Setting up monitoring — physical install
Five steps from inverter commissioning to live dashboard:
Step 1: Network connection. The inverter DataManager has Ethernet, Wi-Fi, and (with the optional Datcom card) cellular. Ethernet is the most reliable for commercial sites — wire to your switch with a Cat5e or Cat6 cable. Wi-Fi works but the inverter's internal antenna is weak inside a metal-clad commercial unit; expect intermittent disconnects without a directional antenna. Cellular at £15-25/month is the right answer for remote rural sites.
Step 2: Solar.web account registration. Go to solarweb.com, sign up, verify email. Most installers register the account in their name during commissioning, then transfer ownership to the site owner — ask your installer to do this rather than starting from scratch.
Step 3: Claim the inverter. Enter the inverter serial number and the system ID printed on a sticker on the inverter front. The platform validates and adds the inverter to your account. Multi-inverter sites: claim each inverter individually, then group them into a "system" in the platform settings.
Step 4: Optional Smart Meter integration. If a Fronius Smart Meter is installed (for self-consumption monitoring), pair it to the inverter via Modbus RTU at install. Solar.web auto-detects and enables the energy balance views.
Step 5: Configure alerts and notifications. In the Settings tab, set up alert thresholds and email recipients. Allow 7 to 14 days of operating data before tuning alert thresholds — the auto-modelled expected values stabilise in the first week.
Multi-site portfolio dashboards
Solar.web Premium's most valuable feature for installers and large commercial customers is the multi-site portfolio dashboard. The view aggregates all inverters across all sites in your account, showing per-site KPIs (today's generation, monthly total, PR, alerts open), with click-through to each site's dashboard. We use this internally for our own portfolio of 350+ Fronius installs across the UK.
The dashboard is filterable by region, by inverter model, by installation date, and by alert status. For an installer running an O&M contract across 50 sites, this is the difference between sustainable maintenance economics and chaos. For a large commercial customer with solar across 12 distribution centres, this is the ESG reporting layer that aggregates portfolio CO2 avoided and lifetime kWh into a single corporate metric.
Comparison: Solar.web vs SolarEdge MySolarEdge
Solar.web is string-level monitoring. MySolarEdge is panel-level. That is the headline difference and it stems from the underlying inverter architecture — Fronius is a string inverter (one inverter handles 8-25 panels per string), SolarEdge is an optimiser-based architecture (every panel has an optimiser reporting back individually).
For warranty claims. SolarEdge faster — per-panel data pinpoints the failing module within hours. Solar.web takes longer because string-level data requires onsite diagnostic to isolate which panel within the string is failing. But Fronius has been replacing more inverters and fewer panels in our experience — the warranty claim profile is different.
For routine monitoring. Both platforms equally good. Both have free tiers, both have mobile apps, both have email alerts.
For multi-site portfolios. Solar.web Premium and SolarEdge organisational dashboards are roughly equivalent. Solar.web slightly cleaner UI in our experience.
For inverter hardware reliability. Fronius and SolarEdge are both solid; failure rates are within 0.5 percent per year for both at 5+ years of field service. The platform decision really hinges on inverter selection at procurement, not the monitoring layer. See /best-commercial-solar-inverters/ for the comparison framework.
Premium tier features and pricing
Solar.web Premium upgrades you from the free LIVE tier and unlocks:
Lifetime 5-minute resolution data retention — versus 12 months in LIVE.
Multi-site portfolio dashboard — the single most useful Premium feature for commercial customers.
Professional report templates — branded PDF reports with site logo, KPIs (PR, specific yield, availability), monthly summaries.
API access — REST API for third-party integration with BI tools, facility management systems.
Custom alerts — granular threshold-based alerting beyond the basic LIVE alerts.
Pricing: ~£3-5 per inverter per year, billed annually, often via your O&M provider. For a 5-inverter commercial site, that is £15-25 per year — usually included in maintenance contracts at no incremental cost. See /services/maintenance/.
Authority resources
Fronius Solar.web platform: solarweb.com. Fronius UK product range: Fronius UK. MCS-listed installer database: MCS Certified. Energy Networks Association G99 grid connection: Energy Networks Association.
Related decision pages
Best commercial solar inverters for the inverter selection comparison. Solar panel monitoring for the broader monitoring picture across platforms. Maintenance contracts for retainer-based monitoring oversight. SolarEdge monitoring for the SolarEdge equivalent. Huawei FusionSolar for the third major platform comparison. SEG tariff comparison for export income optimisation. Commercial solar PV for the underlying business case. Are commercial solar panels worth it. Commercial solar warranty for the warranty framework.
Fronius Solar.web — common questions
How do I set up Fronius Solar.web on my commercial inverter?
Every Fronius commercial inverter ships with a DataManager card already integrated — physical installation is just plugging in Ethernet, Wi-Fi, or cellular and powering the inverter. From the inverter front panel run the WiFi setup wizard or wire Ethernet to your switch. Then go to solarweb.com, register an account, and claim your inverter using its serial number and the system ID printed on the inverter front. Most installs are claimed at handover by the installer and ownership transferred to the site owner — ask your installer to do this rather than starting from scratch yourself, the historical data from commissioning onwards transfers with ownership.
Is Fronius Solar.web free or paid?
The base Solar.web LIVE tier is free for the lifetime of the inverter and gives current generation, today and lifetime production, basic event log, and the energy balance dashboard. Solar.web Premium adds extended historical data retention beyond the LIVE tier, multi-site portfolio dashboards, professional reporting, and advanced KPIs including PR (performance ratio) and specific yield. Premium costs roughly £3 to £5 per inverter per year — typically billed via your installer who buys the licence from Fronius and includes it in O&M contracts. For a single-site commercial customer, LIVE is usually enough; Premium is worth it when you have 5+ inverters across one or more sites.
What is the data resolution Solar.web stores?
Live view runs at 1-minute resolution for the most recent 7 days. Historical data is aggregated to 5-minute resolution for the most recent 12 months and 1-hour resolution beyond that. Solar.web Premium extends 5-minute storage to the lifetime of the system. For most commercial use cases the standard resolution is sufficient — half-hourly meter data from your supplier matches the 5-minute Fronius data well. Where deeper resolution matters (warranty disputes, complex shading analysis), Premium is the right tier.
How does Fronius Solar.web compare to SolarEdge MySolarEdge?
Fronius Solar.web is string-level monitoring; SolarEdge MySolarEdge is panel-level. The granularity gap is the headline difference. On a 30-panel array divided into 3 strings of 10 panels, Solar.web tells you string A is producing X kWh, string B is producing Y kWh, string C is producing Z kWh. MySolarEdge tells you the same plus that within string B, panel 7 is producing 8 percent below the average of panels 1-10. For warranty claim resolution and quick fault location, SolarEdge is faster. For straightforward whole-system monitoring with mature reporting and alerting, Solar.web is more than adequate. Pricing on the Premium tier is comparable. The choice between them happens at inverter selection — Solar.web only works with Fronius inverters; MySolarEdge only works with SolarEdge.
Can I monitor self-consumption and export with Solar.web?
Yes, when paired with the Fronius Smart Meter (sometimes called the Fronius Smart Meter 63A or 65A 3-Phase). The Smart Meter is a current-transformer-based device that sits in your incoming AC distribution board and measures grid import and export in real time. With the Smart Meter installed, Solar.web shows the full energy balance: PV generation, self-consumption, grid import, grid export. Without the Smart Meter, you only see PV generation. For commercial customers chasing SEG income optimisation or reporting self-consumption percentages for ESG, the Smart Meter is essential — adds £200 to £400 at install or £350 to £600 retrofit.
Does Solar.web work with Fronius batteries and other inverter brands?
Solar.web works with all Fronius inverters since 2013 — Tauro (commercial three-phase), Symo (commercial three-phase), Eco (light commercial), Galvo (single-phase), and Primo (residential). For battery storage, Fronius works with the BYD Battery-Box Premium HVS/HVM range and the LG Chem RESU range, plus Fronius’s own GEN24 plus integrated battery options. Solar.web shows battery state of charge and charge/discharge cycles when an integrated battery is present. It does not monitor inverters from other manufacturers — if you have a mixed-brand commercial portfolio with both Fronius and SolarEdge inverters, you need both Solar.web and MySolarEdge platforms or a third-party aggregator like Solytic or PowerDog that pulls APIs from both.