--- title: "Fronius Tauro ECO 99-3-D (Direct) Grid-tie Inverter: Specs & Datasheet | ComparePV" description: "Fronius Tauro ECO 99-3-D (Direct) 99.99 kW grid-tie inverter. Specs: 98.2% European efficiency, 1000 V max DC input, 103.0 kg." source: "https://comparepv.com/inverter/fronius-international-fronius-tauro-eco-99-3-d-direct" updated: 2026-01-16 --- # Fronius Tauro ECO 99-3-D (Direct) ## Identity - **Manufacturer:** Fronius International - **Model:** Fronius Tauro ECO 99-3-D (Direct) - **Series:** Fronius Tauro - **Rated AC power:** 99.99 kW - **Type:** Grid-tie - **Phases:** Three-phase ## How it compares Compared against 243 inverters from 30 to 100 kW. Ranks are within that class. | Measure | This inverter | Class median | Standing | Rank in class | | --- | --- | --- | --- | --- | | European efficiency | 98.2% | 98.2% | Typical | 80 | | MPPT trackers | - | 4 | | | | Max DC input voltage | 1000 V | 1100 V | Typical | 125 | | Weight per kW | 1.0 | 1.1 | Typical | 100 | | Warranty | - | 5 yrs | | | ## Specification ### AC output - **Rated AC power:** 99.99 kW - **Max apparent power:** 99.99 kVA - **Phases:** Three-phase - **Nominal AC voltage:** 400 V - **Max AC current:** 144.9 A - **Grid frequency:** 50 Hz - **Power factor:** 0 - 1 ind. / cap. ### PV input - **Max DC input power:** 150.00 kW - **Max DC voltage:** 1000 V ### Efficiency - **European efficiency:** 98.2 % - **Max efficiency:** 98.5 % ### Physical - **Dimensions:** 755 × 1109 × 346 mm - **Weight:** 103.0 kg - **Enclosure:** IP65 - **Cooling:** forced-air - **Operating temperature:** -40 to 65 °C ### Connectivity and protection - **Interfaces:** Wi-Fi, Ethernet - **Protocols:** Fronius Solar.web, Modbus TCP SunSpec, Fronius Solar API (JSON), Modbus RTU SunSpec (RS485) - **Protection:** AFCI, DC switch, Surge protection ### Warranty and certificates - **Certifications:** AS/NZS 4777.2:2020, IEC 62109-1/-2, VDE-AR-N 4105:2018, IEC 62116, EN 50549-1:2019, EN 50549-2:2019, VDE-AR-N 4110:2018, CEI 0-16:2019, CEI 0-21:2019, IEC 63027:2023 ### Pros - **Active cooling - capable of dissipating heat up to +65°C** - Forced ventilation with an airtight duct maintains full output power even at ambient temperatures up to +65°C, while typical passively cooled inverters (e.g., Sungrow SG110CX) begin to experience derating (reduced performance) starting around +45-50°C. In Polish commercial and industrial rooftop installations, where internal temperatures can exceed 50°C in the summer, this translates to a significantly higher output during peak production periods. - **Modular service - replacement of the Power Stage Set** - In the event of a failure, the technician replaces only the damaged power module (Power Stage Set) without disassembling the entire inverter. The manufacturer claims that the inverter can be serviced by a single person in the field, which reduces the downtime of the installation and lowers maintenance costs compared to devices that require the replacement of the entire unit. - **3 independent MPPT (Tauro standard variant)** - Tauro 50-3-P/D offers 3 separate MPPT tracks with a wide voltage range, which provides a significant advantage in installations with multiple orientations of modules or partial shading. Tauro ECO (1 MPPT) is designed for uniform fields only, and its selection should be a conscious design decision. - **European efficiency: 98.1% (Tauro 50-3-P)** - The certified European efficiency (η\_EU) of 98.1% for the 50-3-P model places the series among the best in the 50-100 kW class. In the Polish conditions, where there are many hours with low and medium solar irradiance, European efficiency is a more important indicator of performance than peak efficiency. - **IP65 rating and operating temperature range: -40°C to +65°C** - The double-reinforced enclosure with IP65 rating and certified operating temperature range from -40°C to +65°C allows for outdoor installation without the need for additional protective enclosures, which reduces BOS (Building Operating System) costs. Nighttime power consumption below 16W minimizes downtime losses during year-round operation. ### Cons - **Clear price premium compared to Tier-1 Asian markets** - Fronius Tauro is a premium-segment product (European manufacturer, Austria). In the 50-100 kW C&I segment, Tier-1 competitors (Sungrow SG110CX, Huawei SUN2000-100KTL) offer efficiencies up to 98.7% (η\_EU) at significantly lower purchase prices - estimated to be 30-50% cheaper. For projects with tight CAPEX budgets, this price difference may be difficult to justify solely based on service benefits. - **Standard 5-year warranty (optional extended warranty available up to 10 years)** - The standard manufacturer's warranty is 5 years; an extended warranty of 10 years (Warranty Plus) is available as a paid option, which must be activated within 30 months of installation. In the C&I segment, some competitors (e.g., SMA) offer similar terms, but investors financing projects with bank loans often require a minimum 10-year warranty as part of the device price. ## About this series The Fronius Tauro series consists of three-phase grid-tie inverters designed for large commercial and industrial installations, where reliability, ease of service, and flexible design are key. What sets them apart is their **actively cooled electronics** and **doubly reinforced housing**, ensuring stable operation in challenging conditions and high ambient temperatures. In practice, this means fewer downtime periods and more predictable energy production. The Tauro variant offers **3 independent MPPTs** - a real advantage in mixed-module orientations, uneven sun exposure, and partial shading, as each string can operate optimally. For projects focused on minimizing system costs, the Tauro ECO with a single MPPT is available. High European efficiency translates to better yields under typical operating conditions in Poland. Monitoring and remote diagnostics via the Fronius ecosystem (portal and service tools) simplify maintenance, and communication via LAN/WLAN supports integration with automation. The series features an indoor and outdoor mounting structure, along with an **IP65 protection rating**. This solution is for investors who expect **fast modular servicing** and reliable performance in C&I installations. ## Questions ### What are the key differences between the Fronius Tauro and the Fronius Tauro ECO? Fronius Tauro is a version with 3 independent MPPT trackers and a wide input voltage range, designed for projects with mixed module orientations or partial shading. Tauro ECO has one MPPT and is optimized for cost-effectiveness, available in 50, 99.99, and 100 kW power ratings. If the installation has a uniform array of modules without shading issues, Tauro ECO allows for reducing the system cost while maintaining the same level of performance. ### What is the warranty on the Fronius Tauro inverter? The standard warranty for the Fronius Tauro series is 5 years. After registering the equipment on the Solar.web portal, the warranty is extended free of charge for up to 10 years. This requires activation within the specified timeframe after installation. This is an important consideration when planning the service budget for a commercial installation with a power output of 50-100 kW. ### Is the Fronius Tauro suitable for installation on the exterior of a building? Yes, the Fronius Tauro series has an IP65 degree of protection, which means it is completely dust-tight and water-resistant. The actively cooled electronics and double-reinforced enclosure allow for operation in harsh weather conditions and at high ambient temperatures. The inverter can be mounted both inside and outside an industrial or commercial building. ### What is the efficiency of the Fronius Tauro inverter, and how does this affect energy yields in Poland? The Fronius Tauro ECO achieves a maximum efficiency of up to 98.2%. Its high efficiency, which takes into account the realistic distribution of solar radiation in a temperate climate, translates into better annual energy yields in Polish conditions. A difference of a few tenths of a percentage point compared to cheaper alternatives with a power of 100 kW means a significantly higher annual energy production. ### What does the monitoring of a Fronius Tauro inverter system look like? The Fronius Tauro inverter is equipped with LAN and WLAN communication, as well as a built-in web server. Production and diagnostic data are accessible via the Fronius Solar.web platform in real-time. This allows the system administrator to remotely monitor performance, detect faults, and request maintenance diagnostics without the need for a physical visit to the site. ### What do the Direct and Precombined variants mean in the Fronius Tauro series, and which one should I choose? The Direct (D) variant allows for the direct connection of DC strings to the inverter, optionally with arc fault protection. The Precombined (P) variant includes a built-in DC connection box, which simplifies wiring in centralized installations. The choice depends on the electrical design: Direct is more flexible, while Precombined reduces installation time when using a larger number of strings. ## Datasheet [Manufacturer datasheet (PDF)](https://comparepv.com/datasheets/inverters/se-ds-fronius-tauro-d-en-158cba981424.pdf) ## Alternatives | Inverter | Rated AC | Euro efficiency | MPPT | Weight | Difference | | --- | --- | --- | --- | --- | --- | | [Fronius Tauro ECO 99-3-P (ECO \| 1 MPPT)](https://comparepv.com/inverter/fronius-international-fronius-tauro-eco-99-3-p-eco-1-mppt) | 99.99 kW | 98.2% | | 103.0 kg | Similar on paper | | [Huawei SUN2000-100KTL-M2](https://comparepv.com/inverter/huawei-sun2000-100ktl-m2) | 100 kW | 98.6% | 10 | 93.0 kg | +0.4 pp efficiency, 10.0 kg lighter | | [Huawei SUN2000-100KTL-M1 (@480 V)](https://comparepv.com/inverter/huawei-sun2000-100ktl-m1-480-v) | 100 kW | 98.6% | 10 | 90.0 kg | +0.4 pp efficiency, 13.0 kg lighter | | [Sungrow SG110CX](https://comparepv.com/inverter/sungrow-sg110cx) | 100 kW | 98.5% | 9 | 89.0 kg | 14.0 kg lighter | | [SMA Solar Sunny Highpower PEAK3 SHP 100-21](https://comparepv.com/inverter/sma-solar-sunny-highpower-peak3-shp-100-21) | 100 kW | 98.5% | 1 | 99.0 kg | 4.0 kg lighter | | [SMA Solar Sunny Highpower Storage SHPS 100-21](https://comparepv.com/inverter/sma-solar-sunny-highpower-storage-shps-100-21) | 100 kW | 98.5% | | 99.0 kg | 4.0 kg lighter | | [Solis-100K-5G](https://comparepv.com/inverter/ginlong-solis-solis-100k-5g) | 100 kW | 98.5% | 9 | 82.0 kg | 21.0 kg lighter | | [Solis-100K-HV-5G](https://comparepv.com/inverter/ginlong-solis-solis-100k-hv-5g) | 100 kW | 98.5% | 9 | 82.0 kg | 21.0 kg lighter | --- Source: https://comparepv.com/inverter/fronius-international-fronius-tauro-eco-99-3-d-direct