Fill the yard with solar. Then see what compute fits.
The tempting move in 2026 is “stand up a mini AI factory.” A Vera Rubin NVL72 is a 72-GPU liquid-cooled cabinet at roughly 180–220 kW IT, 415–480 V three-phase, no air-cooled SKU. Two of them are a 400 kW IT plant before cooling. We flipped the question: cover the yard with solar and batteries, then buy only the compute that 24/7 winter watts can feed.
Where the array and the hut go
Schematic from an aerial takeoff, house-calibrated, not a survey and not the photograph. Water north, road south, trees on the east half. Envelope A is the open yard only — keep the house, pool, driveway, and grove. The hut sits by the existing outbuilding so it does not eat the long solar rows.
Costs
Florida-class insolation (annual 5.2 peak-sun-hours, winter 3.7), 0.80 derate, PUE 1.12 air / 1.18 if you chase NVL8 liquid, 16 hours of facility load through a 0.92 RTE battery. PV at $2.50/W installed for hurricane ground-mount, battery at $400/kWh at this size. Not a bid.
| Envelope | Array | Winter IT | Night BESS | PV + BESS |
|---|---|---|---|---|
| A mid, 95 sq ft/kW (plan) | 189 kW-dc | 20.9 kW | 406 kWh | $636k |
| A mid, 110 sq ft/kW (wind spacing) | 164 kW-dc | 18.0 kW | 351 kWh | $549k |
| A + house roof | 231 kW-dc | 25.4 kW | 495 kWh | $775k |
| B, cut the trees | 653 kW-dc | 68.2 kW | 1.4 MWh | $2.19M |
One DGX Rubin NVL8 is published at about 24 kW wall. Winter-islanded that wants ~230 kW-dc — Envelope A plus the roof, no storm slack. One NVL72 at 200 kW IT wants ~1.9 MW-dc, on the order of 8–10 acres. This lot is ~2 acres upland, half trees.
What 18–21 kW actually buys
Winter 24/7 is the honest number. Summer on Envelope A only climbs to ~30–35 kW IT. Seasonal throttle is extra jobs, not an extra rack.
| SKU | Wall | Count that fits (Envelope A winter) |
|---|---|---|
| DGX Spark | 0.20 kW | ~90–105 |
| DGX Station GB300 (already in the lab) | 1.6 kW | you need one |
| RTX PRO 6000-class box | 0.80 kW | ~23–26 |
| DGX Rubin NVL8 (8× Rubin) | ~24 kW | 0.75–0.87 yard only; ~1.06 with roof |
| HGX B200 8-GPU | ~80 kW | 0.23 |
| Vera Rubin NVL72 | ~200 kW IT | 0.09–0.10 |
| Two NVL72 | ~400 kW IT | 0.05 |
If this were a rental business, eight Rubin GPUs at $6/hr and 50–70% utilization is on the order of $210–294k/year. That is not a datacenter. A hundred Sparks at a soft $0.40/hr is worse as a business and better as what we already do: a lab. Default use of Envelope A is powering the Station and Sparks we already own, islanded.
Not in the drawing: diesel. A week of Gulf cloud still wants a generator or a shutdown. A generator breaks “all solar.” We left it out rather than pretend the battery is seasonal storage.
Method, briefly
- Open-yard area ~18,000 sq ft mid from the aerial (12k–24k band). Packed fixed-tilt 80 sq ft/kW, plan 95, hurricane spacing 110.
- Islanded year-round is winter production, not the annual average.
- NVL72 power from public SemiAnalysis / Flex shelf numbers (180–220 kW/rack, 415–480 V three-phase). NVL8 wall ~24 kW from NVIDIA’s spec page.
- No vendor quotes. No permits. Map is a schematic so we are not publishing the lot photograph.
Next honest step is a tape on Envelope A and one ground-mount bid, not a Rubin purchase order. If the taped yard is 12k sq ft not 18k, every IT watt drops about a third.