Solar on every roof, BOI solar correction, open source section

Solar (user, 17 Oct 2026: "use as much roof space as possible")
- PV on every roof and canopy: ~640 kWp on the Payap scenario plot
  (factory roof ~523, canopies ~54, flat office roof ~65 kWp around the
  AC units); ~300 kWp on the Mueang Chi hall. Calculator: pvKWp 640,
  new pvSelf 85 % (zero export, hourly sketch), PV cost per kWp times the
  array, office-roof PV in the iso view, roofs drawn full.
- 12.8M to 16.6M THB at 20 to 26 THB/W; CSV baseline 34.37M to 56.34M;
  launch plant ~168M / 231M / 294M THB with contingency; Plan B ~216M
  (label ~215M), ~39M above Plan A; Plan A unchanged (it leases the
  array), its solar lever ~17.5M. PV payback ~4.2 to 5.9 years.
- Permits (rooftop solar no factory licence since 28 Dec 2024, ERC
  exemption under 1,000 kVA, PEA zero export) and PPA discounts sourced
  in sustainability.md.

BOI correction
- Announcement 3/2568 (in force 1 July 2025) ended BOI promotion for
  solar installations; only the battery may qualify (12M THB per MW cap).
  Removed the "BOI solar measure" from boi.md, total-investment,
  revenue-model, sustainability, site-candidates and both plan versions;
  Plan B's case for owning the array is the PPA bill it avoids
  (~0.07M USD a year).

Open source (user, 17 Oct 2026)
- digital-factory.md "Open source throughout, and working with other
  plants": everything we run and build is open source on NixOS, our code
  published (licence to decide), vendor firmware the stated exception;
  later the stack and factory-automation services for other pressing
  plants, not in the revenue.
- Business plan section 5.6 plus an executive-summary bullet, reading
  guide and not-modelled mentions; draft 0.3 rebuilt (A 60, B 61 pages),
  renders re-made with the roofs full.

docs/boi.md

@@ -15,13 +15,25 @@ no corporate income tax holiday on the core pressing activity, but the full
 non-tax package and machinery duty exemption. The tax value is engineered on
 top through the upgrade measures, where this project happens to be strong:
 
-- **Solar and battery**: the alternative-energy measure (Announcement
-  2/2568, April 2025, under the Smart and Sustainable Industry framework)
-  grants CIT exemption based on the solar investment. Eligible spend
-  explicitly includes PV modules, inverters, BESS and BESS inverters, and
-  mounting structures, capped at THB 12M/30M/40M of investment value per MW
-  depending on investment type. The planned Deye + Gobel installation
-  converts directly into CIT-exemption headroom.
+- **Solar: no longer promoted; the battery may be.** The alternative-energy
+  measure (Announcement 2/2568, April 2025, under the Smart and Sustainable
+  Industry framework) granted a CIT exemption on the solar investment,
+  capped at THB 12M/30M/40M per MW. **Announcement 3/2568** (5 June 2025,
+  in force 1 July 2025) ended promotion for installing solar power
+  generation under that measure for applications from 1 July 2025; what
+  remains is machinery modified to use other renewable energy, and battery
+  storage (BESS) with its inverters, the eligible investment capped at
+  THB 12M per MW
+  ([B Global Law](https://bgloballaw.com/2026/01/18/boi-announcement-no-3-2568-amendment-to-renewable-energy-efficiency-enhancement-measures),
+  [Smarter Energy Solution](https://smarterenergysolution.com/blog/boi-solar-thailand-2026),
+  checked October 2026). So owning the ~640 kWp array earns no BOI
+  benefit; its case is the bill (see [sustainability](sustainability.md)).
+  Whether the 271 kWh battery qualifies is for the BOI consultant. A PPA
+  developer selling solar power (200 kW or more per distribution point)
+  can still be promoted under activity 7.1.2 (8-year CIT exemption); that
+  benefit is the developer's, and how much of it reaches the PPA price is
+  a negotiation
+  ([CapSolar](https://capsolar.co.th/en/knowledge/boi-solar-incentives-2026)).
 - **Automation and metrology**: the Smart and Sustainable Industry upgrade
   measure (Announcement 15/2565, refreshed July 2025) rewards automation,
   smart machinery, and energy efficiency, typically 3 years of CIT
@@ -33,8 +45,8 @@ top through the upgrade measures, where this project happens to be strong:
   galvanics process development, and recycled-PVC work could be framed as
   qualifying development.
 
-So the application is pitched on solar, automation, and technology content,
-not on "we press plastic discs."
+So the application is pitched on automation and technology content (and
+the battery, if it qualifies), not on "we press plastic discs."
 
 ## What Group B still delivers (the core value)
 
@@ -119,11 +131,13 @@ project timeline, ahead of equipment contracts.
 
 - Confirm the exact activity sub-code and tier for vinyl/PVC consumer-goods
   pressing (Group B assumption is well supported but not code-verified)
-- Confirm the live versions and per-MW caps of the solar and
-  smart-and-sustainable measures at filing time
+- Confirm the live version of the smart-and-sustainable measures at
+  filing time, and whether the battery qualifies under the BESS part of
+  the alternative-energy measure (THB 12M per MW cap); solar itself is out
+  since 1 July 2025 (Announcement 3/2568)
 - Confirm current NEC/Lamphun area add-ons
 - Engage a BOI-registered consultant to structure the application so the
-  solar, automation, and R&D measures stack on the base promotion
+  automation and R&D measures (and the battery) stack on the base promotion
 - Check whether R&D contracted with Payap University and the joint student
   programmes ([Payap partnership](payap-partnership.md)) count toward the
   R&D merit or a skills-development measure