Operating colocation at Stadlauer Strasse 66, supporting geographic redundancy with Nessus’s southern Vienna sites through a route-redundant fibre ring. Published cooling uses cold-aisle containment and…
Read overviewNessus Data Center 3
Vienna, Austria
Watch this site
Watch Nessus Data Center 3
Register interest in updates to planning status, grid position, capacity claims, delivery teams and policy exposure. Every Power Reality Check client receives 60 days of Site Watch on their assessed site when monitoring is available.
3 cited sources · 6 utility and planning categories reviewed.
Review evidence and gapsVerify the import contract, network operator, energised load and customer availability.
Open the full checkOverview
Operating colocation at Stadlauer Strasse 66, supporting geographic redundancy with Nessus’s southern Vienna sites through a route-redundant fibre ring. Published cooling uses cold-aisle containment and adiabatic systems; ownership and construction appointments remain unverified.
- Developer / applicant
- Nessus GmbH
- Owner
- Not verified
- Operator
- Nessus GmbH
Planning and delivery status
Operator facility page and dated issuer release explicitly identify commencement on 1 May 2025; 19 September and 7 October 2025 are later publication dates.
Stage source: 1 May 2025Project intelligence. This record does not establish that the land or facility is available to acquire.
POWER STUDY
Power
What the power evidence establishes
The site-specific connection scope has not been established for this record.
Power classDNo qualifying rung
No same-scope, dated import-MVA rung has document-seen or better verification. Nearby infrastructure, IT MW and marketing claims cannot upgrade the class.
The class describes published documentary evidence at its stated date. It does not prove current contractual rights, transferability or an energisation date.
Class describes evidence maturity. Public records do not prove current contractual rights, transferable capacity or an energisation date. This record has not received a complete power study review.
Read the rules and verification levels01
Capacity ladder and evidence
Each rung is a separate MVA claim for its stated site or phase. A missing rung is unknown.
01
Applied
Unknown
Not established from the public records reviewed.
What applied mva is evidenced for the assessed site scope?02
Offered
Unknown
Not established from the public records reviewed.
What offered mva is evidenced for the assessed site scope?03
Accepted / contracted
Unknown
Not established from the public records reviewed.
What accepted or contracted mva is evidenced for the assessed site scope?04
Energised
Unknown
Not established from the public records reviewed.
What energised mva is evidenced for the assessed site scope?02
Conflicts and scope comparisons
No conflicting pair is recorded. This does not establish that all public statements have been reconciled.
03
Austria grid context
Network publications frame the claim. They do not allocate capacity to this site.
No country context entries have been linked to this site. Applicable policy, capacity information and reinforcement dependencies need review.
04
Derived energisation window
Earliest plausible yearUnknown
Latest plausible yearUnknown
The observed inputs do not establish a bounded delivery range. Open bounds stay unknown.
Rule
Use only a same-scope, dated, document-verified capacity rung and an applicable duration to energisation published by the observed site operator. The named process operator and a named source publisher must match that operator. Earliest year is the maximum of stage date plus minimum duration and each evidenced readiness constraint. Latest year is the maximum of stage date plus maximum duration and each published upper constraint only when every required input is bounded. An offer-processing duration is excluded. A missing required input leaves the affected bound unknown; no padding or contractual delivery promise is inferred.
No observed inputs establish this result.
Dependencies driving the range
- Connection-dependent reinforcement scope and completion dates: unknown.
- Grid-works planning status and programme: unknown.
- Applicable connection-policy conditions and programme: unknown.
What the earliest case requires
- Connection-dependent reinforcement scope and completion dates introduces no later constraint than the earliest case; this remains unverified.
- Grid-works planning status and programme introduces no later constraint than the earliest case; this remains unverified.
- Applicable connection-policy conditions and programme introduces no later constraint than the earliest case; this remains unverified.
Missing inputs leave the range open
- A dated, document-verified import-MVA rung for the assessed scope.
- An applicable duration from the evidenced stage to energisation, published by and matched to the observed site operator, rather than an offer-processing target.
- Connection-dependent reinforcement scope and completion dates
- Grid-works planning status and programme
- Applicable connection-policy conditions and programme
05
Indicative HV and connection capex
Unknown
Rule and scope
Sum each published complete scope quantity multiplied by the matching published benchmark minimum and maximum. Configuration, voltage, route type, unit, country applicability, currency and explicit price base year must match. No assumed route length, transformer count, exchange rate, inflation, fee uplift or partial index is inserted. The result is an indicative benchmark band, not an operator quotation or contractual connection charge.
No observed inputs establish this result.
Scope questions
- Obtain a published complete connection scope with voltage, configuration and measured quantities.
- Establish that every necessary connection-work component is included in the published scope.
- Identify network and customer works, upstream reinforcement, land and wayleaves, taxes, fees, securities, contingency and the price base.
06
Alternatives and policy exposure
Behind-the-meter generation
Unknown
Not established from the public records reviewed.
What behind-the-meter generation is evidenced, and at what scope?Planning / policy requirement
Unknown
Not established from the public records reviewed.
Does the applicable planning or connection policy require behind-the-meter generation?Battery storage
Unknown
Not established from the public records reviewed.
What battery storage is evidenced, and at what scope?Planning / policy requirement
Unknown
Not established from the public records reviewed.
Does the applicable planning or connection policy require battery storage?Private wire
Unknown
Not established from the public records reviewed.
What a private wire is evidenced, and at what scope?Planning / policy requirement
Unknown
Not established from the public records reviewed.
Does the applicable planning or connection policy require a private wire?Gas
Unknown
Not established from the public records reviewed.
What gas supply or generation is evidenced, and at what scope?Planning / policy requirement
Unknown
Not established from the public records reviewed.
Does the applicable planning or connection policy require gas supply or generation?Connection claim against current policy
Unknown
Not established from the public records reviewed.
Does the published connection claim meet the policy applicable to its application date, location and agreement status?07
Open questions for a Reality Check
Generated from unknown fields, missing derivation inputs and unresolved evidence. The questions identify the documents or specialist checks needed next.
60 questions to resolve
- Which TSO or DSO is responsible for this demand connection?
Not established from the public records reviewed.
- What is the operator-confirmed connection substation or circuit?
Not established from the public records reviewed.
- What voltage level is specified for the demand connection?
Not established from the public records reviewed.
- What are the evidenced site and connection-point coordinates, and their calculated straight-line distance?
Not established from the public records reviewed.
- What grid route length is published, and for which circuit?
Not established from the public records reviewed.
- What applied mva is evidenced for the assessed site scope?
Not established from the public records reviewed.
- What is the effective date of the applied connection evidence?
Not established from the public records reviewed.
- Which buildings or phases does the applied connection evidence cover?
Not established from the public records reviewed.
- What evidence level can be supported for capacityLadder.applied?
Verification has not been established.
- What offered mva is evidenced for the assessed site scope?
Not established from the public records reviewed.
- What is the effective date of the offered connection evidence?
Not established from the public records reviewed.
- Which buildings or phases does the offered connection evidence cover?
Not established from the public records reviewed.
- What evidence level can be supported for capacityLadder.offered?
Verification has not been established.
- What accepted or contracted mva is evidenced for the assessed site scope?
Not established from the public records reviewed.
- What is the effective date of the accepted connection evidence?
Not established from the public records reviewed.
- Which buildings or phases does the accepted connection evidence cover?
Not established from the public records reviewed.
- What evidence level can be supported for capacityLadder.accepted?
Verification has not been established.
- What energised mva is evidenced for the assessed site scope?
Not established from the public records reviewed.
- What is the effective date of the energised connection evidence?
Not established from the public records reviewed.
- Which buildings or phases does the energised connection evidence cover?
Not established from the public records reviewed.
- What evidence level can be supported for capacityLadder.energised?
Verification has not been established.
- What connection agreement type and current status are documented?
Not established from the public records reviewed.
- Does the agreement impose phased import-capacity limits?
Not established from the public records reviewed.
- What flexibility or curtailment obligations apply?
Not established from the public records reviewed.
- What on-site generation obligations apply?
Not established from the public records reviewed.
- What securities are required, posted and still valid?
Not established from the public records reviewed.
- What connection longstop or milestone dates apply?
Not established from the public records reviewed.
- What is the published IT load in MW?
Not established from the public records reviewed.
- On what electrical basis is the IT load in MW stated?
Not established from the public records reviewed.
- Which phase or campus does the IT load in MW cover?
Not established from the public records reviewed.
- What is the published facility load in MW?
Not established from the public records reviewed.
- On what electrical basis is the facility load in MW stated?
Not established from the public records reviewed.
- Which phase or campus does the facility load in MW cover?
Not established from the public records reviewed.
- What is the published import capacity in MVA?
Not established from the public records reviewed.
- On what electrical basis is the import capacity in MVA stated?
Not established from the public records reviewed.
- Which phase or campus does the import capacity in MVA cover?
Not established from the public records reviewed.
- What operator-published connection-to-energisation duration applies to this site and connection stage?
An application-to-offer processing target is not an energisation duration.
- Which reinforcements does the connection depend on, and what dates are published?
Not established from the public records reviewed.
- Which grid works require planning, and what is their current consent status and dated programme?
Not established from the public records reviewed.
- Which connection-policy conditions apply, and when could they be satisfied?
Not established from the public records reviewed.
- What complete connection scope is published: bays, stations, voltage, circuits, route lengths and underground or overhead configuration?
Not established from the public records reviewed.
- Is the published connection scope complete enough to match every component to a sourced benchmark?
Not established from the public records reviewed.
- What behind-the-meter generation is evidenced, and at what scope?
Not established from the public records reviewed.
- Does the applicable planning or connection policy require behind-the-meter generation?
Not established from the public records reviewed.
- What battery storage is evidenced, and at what scope?
Not established from the public records reviewed.
- Does the applicable planning or connection policy require battery storage?
Not established from the public records reviewed.
- What a private wire is evidenced, and at what scope?
Not established from the public records reviewed.
- Does the applicable planning or connection policy require a private wire?
Not established from the public records reviewed.
- What gas supply or generation is evidenced, and at what scope?
Not established from the public records reviewed.
- Does the applicable planning or connection policy require gas supply or generation?
Not established from the public records reviewed.
- Does the published connection claim meet the policy applicable to its application date, location and agreement status?
Not established from the public records reviewed.
- Which checked country-grid sources and location-specific constraints apply to this connection?
No country-context relationship has been established for this record.
- Identify network and customer works, upstream reinforcement, land and wayleaves, taxes, fees, securities, contingency and the price base.
Connection-cost scope question.
- Resolve the energisation input: A dated, document-verified import-MVA rung for the assessed scope.
This missing input leaves an energisation bound unknown.
- Resolve the energisation input: An applicable duration from the evidenced stage to energisation, published by and matched to the observed site operator, rather than an offer-processing target.
This missing input leaves an energisation bound unknown.
- Resolve the energisation input: Connection-dependent reinforcement scope and completion dates
This missing input leaves an energisation bound unknown.
- Resolve the energisation input: Grid-works planning status and programme
This missing input leaves an energisation bound unknown.
- Resolve the energisation input: Applicable connection-policy conditions and programme
This missing input leaves an energisation bound unknown.
- Obtain a published complete connection scope with voltage, configuration and measured quantities.
This scope or reference gap prevents a complete indicative connection capex band.
- Establish that every necessary connection-work component is included in the published scope.
This scope or reference gap prevents a complete indicative connection capex band.
Use these questions to scope a Power Reality Check.
Request an assessment of this record and the evidence needed next. Share only public information or documents you are authorised to provide.
Request a Reality CheckEarlier capacity notes and source context
14 MW importProject capacity
Operator-stated 14 MW Anschlussleistung (connection power) for NDC3. Utility contract, allocated/energised amount and spare headroom are not disclosed; no MVA conversion.
Published claimProject source recordImport rights and connection evidence
Nessus publishes 14 MW connection power, redundant transformers, five diesel sets and rotary UPS. It publishes neither the utility agreement nor available import headroom.
IT load, facility demand, import capacity and equipment ratings retain their stated scope. A published figure does not establish spare or transferable supply.
Planning & utilities
6 of 10 categories contain evidence. Each status applies to its specific claim.
Grid & import rights
Partial evidenceNessus publishes 14 MW connection power, redundant transformers, five diesel sets and rotary UPS. It publishes neither the utility agreement nor available import headroom.
Sources & next check
Fibre & dark fibre
DocumentedThe 19 September 2025 operator article states all three Vienna locations share a route-redundant fibre ring. The facility page lists A1, Magenta, Colt and other fibre carriers.
Sources & next check
Land, footprint & access
Partial evidenceOperator identifies 2,400 m² total NDC3 facility area at Stadlauer Strasse 66. This is not an exclusive parcel size or evidence of remaining expansion land.
Sources & next check
Water, cooling & heat
Partial evidenceOperator describes cold-aisle containment and adiabatic cooling; the facility page states N+1 cooling. Evaporative water demand, discharge and heat off-take are not disclosed.
Sources & next check
Demand & location fit
DocumentedNDC3 in Donaustadt adds geographical redundancy to the two Nessus sites in Favoriten, connected by the operator’s ring. This supports an intra-Vienna resilience use case.
Sources & next check
Programme & delivery
DocumentedNessus’s dated 7 October 2025 release explicitly confirms NDC3 began operating on 1 May 2025. The September opening article is a publication milestone, not a different start date.
Sources & next check
Not assessed
Planning & decisionsLand-use zoningOwnership & development controlFlood, ground & environment
Evidence still needed
- Planning & decisions
A current planning decision, conditions and any appeal or court proceedings still need to be checked.
- Land-use zoning
The site boundary has not been matched to the current adopted zoning map and data-centre use policy.
- Ownership & development control
Legal title, land-owning entity, development-control route and restrictions need verification. A named developer does not establish availability.
- Flood, ground & environment
Flood risk, ground conditions, contamination, ecology, heritage, noise and air-quality constraints have not been fully assessed here.
Project team
Appointments are limited to the project, phase and scope supported by each source.
No project-specific team appointments have been verified for this record.
Sources
Publication dates are shown where known. Review dates do not establish approval or commissioning.
- Nessus: NDC3 facility, opening date and connection powernessus.at · Publication date unstated
- Nessus — NDC3 opening, diverse fibre ring and cooling designnessus.at · 19 Sept 2025
- Nessus issuer release — NDC3 began operating 1 May 2025ots.at · 7 Oct 2025
Original documents and maps retain their rights. Public access does not grant commercial redistribution rights.