Piller Power Systems UNIBLOCK UBT+ rotary UPS, 150 kW to 50 MW
Piller's mechanically coupled rotary UPS from 150 kW to 50 MW, now being displaced by the electrically coupled UB-V
This model is part of SecondWatt’s ups system research catalogue. Specifications and price observations are included where supported by sources. Equipment availability and commercial terms require confirmation.
Piller UNIBLOCK UBT+ dossier: rotary UPS from 150 kW to 50 MW, 97% efficiency, UB-V succession, parts and capacitor inspection points, and market context.
UNIBLOCK UBT+ is Piller's rotary hybrid UPS, covering 150 kW to 50 MW in the UNIBLOCK series with the diesel rotary UBTD+ sibling running 500 kW to 40 MW. Energy storage is an option between batteries and a POWERBRIDGE flywheel, cooling is air or chilled water, and containerized builds are available for low and medium voltage applications. Piller's own history page states real efficiencies at 97% for the 2008 to 2014 UBT+ and UBTD+ range.
The generational point matters for residual value. UBT+ is a mechanically coupled legacy architecture, while Piller's current data center flagship is the electrically coupled UB-V Series at 1,100 kVA to 3,600 kVA, marketed as new with its own product pages. The UB-V reaches up to 98% at full load and 97% at half against a benchmark of 96.3% for conventional static UPS, claims a single-unit mean time between failures five times a typical static UPS, saves more than 20% of plant room space, and extends service intervals to once every five years using condition monitoring while carrying no power capacitors and no electric fans.
That last claim is the inspection lead for a used UBT+. If the UB-V is differentiated by having no power capacitors and no electric fans, then UBT+ generation units do contain both, and both are finite-life consumables on a machine built between 2008 and 2014. Piller's after-sales organisation performs preventative maintenance to extend UPS life to at least twenty years and holds stocked parts at service centres worldwide, so parts risk is low relative to a discontinued third-party line.
Why it matters
Piller is a supplier whose new-build slots are sold out for 2026 and nearly all of 2027, with the parent reporting Power Solutions orders on hand of 1,952 million euros at the end of 2025 against revenue of 793 million. That is the classic condition that creates a secondary-market premium, the same dynamic seen in gas turbines applied to rotary UPS.
Who buys it
Large data center, industrial and institutional buyers who want a rotating machine in the power path with high fault current capability and an optional integrated diesel, and owners of an installed UBT+ fleet buying service or spares. New data center buyers are now steered toward the UB-V Series, which is where Piller has put its data center marketing.
Role in the data center
Facility-scale rotary UPS from a single 150 kW machine to a 50 MW installation, sitting in the power path as a rotating machine rather than a static converter, often paired with gensets in a DeRUPS or isolated parallel architecture. Cooling is air or chilled water and containerized builds are offered, so siting is a mechanical decision as much as an electrical one.
Key specifications
| Series power range | 150 kW to 50 MW |
|---|---|
| Diesel rotary sibling range | 500 kW to 40 MW (UBTD+) |
| Energy storage options | Batteries or POWERBRIDGE flywheel |
| Cooling options | Air or chilled water; containerized builds available |
| Stated efficiency | 97 (real efficiencies, 2008-2014 range) % |
| Architecture | Mechanically coupled rotary hybrid |
| Successor rating | 1,100 kVA (1.0 MW) to 3,600 kVA (3.24 MW), UB-V Series |
| Successor efficiency | up to 98 at full load, 97 at half load % |
| Successor reliability claim | Single-unit MTBF rises by a factor of 5 against a typical static UPS |
| Successor space saving | more than 20 of plant room space % |
| Successor service interval | extendable to once every 5 years with condition monitoring |
| Service-supported life | at least 20 years |
| DeRUPS architecture | Diesel genset upstream or downstream of the UBT+, no freewheel clutch |
Technical summary
Series range: 150 kW to 50 MW (UNIBLOCK series); UBTD+ diesel rotary 500 kW to 40 MW. Energy storage: batteries or POWERBRIDGE flywheel, specified per project. Cooling: air or chilled water; containerized options available. Voltage: low and medium voltage applications. Efficiency: real efficiencies at 97% stated for the 2008-2014 UBT+ and UBTD+ range. Architecture: mechanically coupled rotary hybrid; UB-V successor is electrically coupled. Successor rating: UB-V Series at 1,100 kVA (1.0 MW) to 3,600 kVA (3.24 MW). Successor efficiency: up to 98% at full load and 97% at half load. Successor service interval: extendable to once every five years with condition monitoring. Service-supported life: preventative maintenance to extend system life to at least 20 years.
Major variations
UBT+ rotary and UBTD+ diesel rotary, at 150 kW to 50 MW and 500 kW to 40 MW respectively, each specifiable with battery or POWERBRIDGE flywheel storage, air or chilled water cooling, and containerized builds for low and medium voltage applications. System-level configurations include DeRUPS, which integrates a diesel genset upstream or downstream of the UBT+ with no freewheel clutch and does not require the genset count to match the UPS count, and Isolated Parallel architecture for large halls. Piller's current data centre flagship is the electrically coupled UB-V Series at 1,100 to 3,600 kVA, which is a different architecture rather than a UBT+ variant.
Configurations and options
The UNIBLOCK order is a set of architecture choices rather than a model number. UBT+ is the rotary machine at 150 kW to 50 MW; UBTD+ is the diesel rotary sibling at 500 kW to 40 MW. Energy storage is specified per project as either a battery plant or a POWERBRIDGE flywheel, and each carries a different consumable and a different service regime. Cooling is air or chilled water, which decides whether the installation needs a plant tie-in or only room air. Containerized builds are offered, and the range covers low and medium voltage applications. At system level, the DeRUPS configuration integrates a diesel set upstream or downstream with no freewheel clutch and does not require the generator count to match the UPS count, and Isolated Parallel is the architecture offered for large halls.
Compatibility and dependencies
This is a mechanically coupled rotating machine in the power path, so the coupling itself, the paired energy store and, on a UBTD+ or DeRUPS build, the diesel set are all part of the asset rather than accessories to it. A chilled water build ties into a cooling circuit and cannot be dropped into a room designed for an air-cooled machine. Medium voltage applications mean the unit can sit on an MV bus rather than behind a 480 V board, which changes the upstream one-line. Piller publishes no per-model kVA table, no input and output voltage set and no UL 1778 or IEC 62040-3 statement for the UBT+ specifically as of September 2026, so voltage, frequency and certification have to be read from the individual machine and its commissioning file. Condition telemetry does not transfer either: e-VENTLOG monitoring belongs to the newer UB-V series, so a used UBT+ arrives with no service history.
Pricing and availability
Trend: rising Langley Holdings, Piller's parent since 2005, reported in its 2025 annual report announced 6 February 2026 that Power Solutions division revenue reached 793m euro on 1,952m euro of orders in hand at year end, with group orders doubling to 2,069.4m euro from 930.4m euro in 2024, and stated that capacity for the largest behind-the-meter data center power equipment is sold out for 2026 and nearly all of 2027, with demand outstripping supply several times over. Lead time, used or refurbished: No used or refurbished unit listed as of August 2026. Warranty, used: 1-year typical from refurbishment dealers.
Lifecycle and maintenance
Piller's after-sales organisation performs preventative maintenance to extend UPS system life to at least 20 years and holds stocked parts at service centres across more than 40 countries with 24/7 coverage, so parts risk on a UBT+ is low relative to a discontinued third-party line. The maintenance profile is set by what the successor does not have: Piller advertises the UB-V Series as carrying no power capacitors and no electric fans and as extending service intervals to once every five years with e-VENTLOG condition monitoring, which means UBT+ generation machines built between 2008 and 2014 do contain both, and both are finite-life consumables. Piller publishes no MTBF hours, no bearing type and no service interval for the UBT+ itself.
Thermal and emissions profile
Flywheel and rotary UPS produce no combustion emissions and carry no battery at all, which removes the category's largest environmental liability: no lead-acid recycling stream, no lithium fire code, and what Piller describes as no environmental disposal concerns at end of life. The second-order saving is cooling. Batteries need a controlled room at 25 degrees C or lower to reach rated life, while VYCON states the VDC needs no cooling and Piller states air conditioning is not required for POWERBRIDGE. Active Power rates CleanSource HD to 104 degrees F (40 degrees C) at 96.5% efficiency on half load and up to 98% at full load, so the parasitic cooling load a battery room imposes never appears.
Common failure points
- Power capacitors — The UB-V successor is marketed as having none, which places a finite-life capacitor bank inside a UBT+ generation machine
- Electric fans — The same comparison implies fans in the UBT+ generation, and a failed fan drives a transfer to bypass
- Coupling and clutch — Piller advertises its DeRUPS configuration as having no freewheel clutch, marking the clutch and coupling as a wear item on earlier and competing designs
- Controls and diagnostics generation — e-VENTLOG condition monitoring belongs to the newer series, so a used UBT+ arrives with no telemetry history
- Paired energy store — Storage is an option between batteries and a POWERBRIDGE flywheel, and each carries a different consumable
Inspection checklist
Establish capacitor age first; Piller markets the UB-V successor as having no power capacitors and no electric fans, which places both inside a 2008 to 2014 UBT+. Ask for the fan replacement record and listen at the air intake. Confirm the coupling type and its condition, because Piller advertises its DeRUPS configuration as having no freewheel clutch and that marks the clutch as a wear item elsewhere. Establish the storage configuration, batteries or POWERBRIDGE flywheel, and inspect whichever is fitted on its own terms. Confirm the cooling arrangement, air or chilled water, against the room it is going into. Ask Piller in writing for parts entitlement against the specific serial and vintage. Price a controls retrofit, since e-VENTLOG diagnostics belong to the newer series.
Procurement channels
Direct from Piller, quoted project by project. Piller maintains stocked parts at service centres worldwide with 24/7 coverage across more than 40 countries, so service and spares are an OEM channel rather than an independent one.
Regional notes
Sold globally from Osterode am Harz, Germany, through Piller subsidiaries, with US coverage running through the same group that has owned Active Power in Austin, Texas since November 2016. Piller publishes no per-region rating table, no input and output voltage set and no UL 1778 or IEC 62040-3 statement for the UBT+ specifically, so certification has to be confirmed against the individual machine.