Technical Specification — Replace busway with 800-1000 A and new tap-off units

1. Purpose

This package procures the works required to relieve Busway ampacity in hall DH-02. In the capacity model for this hall that constraint is what limits deployable rack count; relieving it moves the hall from 12 to 22 racks, and it is part of a programme that reaches 62 racks in total.

Duties in section 3 are sized for the end state of 62 racks of NVIDIA GB300 NVL72 — the hall this relief is part of delivering — not for the 10 rack(s) this single step unlocks on its own. Nobody buys plant for a marginal rack.

In the capacity model this step moves the hall from 12 to 22 racks; the full ladder reaches 62.

Every numeric requirement is derived from the capacity model and names the constraint it came from. Nothing here specifies a make or a model: we state the duty and the interfaces, the supplier proposes the equipment, and we take no margin on it.

The budget figure is our modelled estimate, not a price. It is stated so the client can see whether a response is in the right universe, and it carries its own evidence class.

2. Scope of supply

Included in this package:

• Supply — Equipment meeting the duty specified in section 3.
• Delivery — Delivered to site, offloaded, positioned.
• Installation and commissioning — Installation in a live hall, commissioning and witnessed testing.
• Documentation — Test certificates, selection outputs at site conditions, O&M.

Explicitly excluded. Listed rather than omitted, because an unstated exclusion is a gap somebody discovers on site:

• Structural sign-off — Any structural strengthening arising from the works is by others.
• Protection and arc-flash studies — Provided by the client's electrical engineer.
• Migration and tenancy — Moving or decanting existing tenants is outside this package.

2A. Site conditions and assumptions

Every duty in section 3 is quoted at these site conditions. Each numeric requirement in section 3 is derived from the constraint named in its 'From constraint' column, and these conditions are the model inputs those constraints used. A condition the client did not supply is printed as 'not supplied: assumed ...' with its evidence class; it is not a measurement and is not silently defaulted. A responder who has better data for any line shall say so in the response.

Values carry their unit and evidence class (E0 assumed ... E7 observed). 'library' is a platform figure; 'not modelled' means the engine has no input for the condition and has applied no derating for it.

Inputs to the capacity model that were assumed rather than supplied (each is an assumption at evidence class E0 unless it states otherwise):

• Installed CDU schedule (thermal.cdus): not supplied: assumed nothing: no value was assumed in its place and the constraint it feeds is not assessed (E0)
• TCS target supply temperature (thermal.tcs_target_supply_C; degC): not supplied: assumed 30 [27–32] degC (E0)
• Rear-door heat exchanger capacity per rack (thermal.rdhx.capacity_kW_per_rack; kW): not supplied: assumed 60 [20–80] kW (E0)
• All-in grid electricity price (economics.electricity_eur_per_MWh; EUR/MWh): not supplied: assumed library placeholder of 140 EUR/MWh (E0)
• Discount rate (economics.discount_rate): not supplied: assumed no value (none: the lifecycle value is undiscounted) (E0)

3. Technical requirements

Obligation words carry their usual tender meaning: shall — non-compliance disqualifies the response; should — scored, not disqualifying; may — stated for context.

Every numeric requirement names the constraint it was derived from. A requirement nobody can trace back to a physical limit is one somebody invented.

**E-10 — Busway continuous ampacity** (shall). Each busway run shall have a continuous ampacity not less than the figure stated, at the hall's design ambient and installed configuration.

*Verification:* Type test certificate to the applicable standard, with derating basis stated.

**E-11 — Phasing and outage** (shall). The programme shall allow replacement run by run with the hall in service. The response shall state the outage window per run.

*Basis:* Live tenancy in the hall during the works.

*Verification:* Method statement and programme.

**E-12 — Tap-off provision** (shall). Busway shall accept tap-off units at the density required by the rack pitch stated in the response schedule.

*Basis:* Hall aisle configuration; 62 positions to be fed.

*Verification:* Layout drawing.

**C-01 — Price basis** (shall). Prices shall be delivered and installed, excluding VAT, in EUR, with exclusions listed separately.

*Basis:* Comparability. Four quotations on four bases cannot be evaluated.

*Verification:* Completed response schedule.

**C-02 — Validity** (shall). Prices shall remain valid for not less than 60 days.

*Basis:* The evaluation and approval cycle on a capital item of this size.

*Verification:* Stated on the quotation.

**C-03 — Response schedule** (shall). The response schedule in section 6 shall be returned completed. An incomplete schedule will not be evaluated.

*Basis:* Every figure in it feeds a comparison the client can check. A bid that answers a different question cannot be compared with one that answers this one.

*Verification:* Returned document.

4. How responses will be evaluated

Price is one criterion of five. The item being bought exists to unlock compute on a date: a response that is cheaper and materially slower is the expensive one, and the weighting says so.

Weights total 100.

5. Instructions to responders

• Return the response schedule in section 6, completed. An incomplete schedule is not evaluated.
• State compliance against every requirement in section 3 as C (compliant), CD (complies with deviation, deviation described) or N (non-compliant).
• Quote duties at the site conditions stated in section 2A, not at a reference condition. A duty at a reference condition is not a response to this document.
• List exclusions explicitly and price them separately where you can.
• State which long-lead component governs your delivery date.

6. Response schedule

Return these figures in these units. They feed a comparison the client can check line by line, which is only possible if every response answers the same question.

Machine-readable template: `gridforge spec … --template` writes a JSON file with these keys, which `gridforge bids` reads back.

Appendix A — Assumptions, provenance and validation status

Every number in this report carries an evidence class. The class of a computed number is never higher than the weakest of its inputs, so a model applied to measured data yields a modelled number and never a measurement.

E5 means supplied by the client — a declared rating, contract term or design value, or the client's own data as given. It is not a measurement we made, and it has not been verified by a site survey.

A.1 Assumptions relied upon

• Placeholder re-expressed per run from the earlier 450 kEUR lump for the reference hall's 8 runs. Not a market price.
• Library default, not a price. Replace with a quotation before this figure supports a capital decision.
• Tap-off units are a reported shortage item
• Legacy low-temperature plant
• Operators specify 27-30 degC for 500-700 W parts; the W45 equipment rating is not an operating point
• Cold plates on CPU/GPU/HBM/NVSwitch; residual air load must still be removed

A.2 Sources

• DCD, hot water cold water, 2024
• Lenovo Press LP2357, GB300 NVL72, 2026 [V]
• NVIDIA NVL72 AI Factory Reference Architecture, 2026 [V]

A.3 Provenance of headline quantities